1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file:
30 *
31 * ASM: a very small and fast Java bytecode manipulation framework
32 * Copyright (c) 2000-2011 INRIA, France Telecom
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the copyright holders nor the names of its
44 * contributors may be used to endorse or promote products derived from
45 * this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
57 * THE POSSIBILITY OF SUCH DAMAGE.
58 */
59 package jdk.internal.org.objectweb.asm;
60
61 import java.io.ByteArrayOutputStream;
62 import java.io.IOException;
63 import java.io.InputStream;
64
65 /**
66 * A parser to make a {@link ClassVisitor} visit a ClassFile structure, as defined in the Java
67 * Virtual Machine Specification (JVMS). This class parses the ClassFile content and calls the
68 * appropriate visit methods of a given {@link ClassVisitor} for each field, method and bytecode
69 * instruction encountered.
70 *
71 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html">JVMS 4</a>
72 * @author Eric Bruneton
73 * @author Eugene Kuleshov
74 */
75 public class ClassReader {
76
77 /**
78 * A flag to skip the Code attributes. If this flag is set the Code attributes are neither parsed
79 * nor visited.
80 */
81 public static final int SKIP_CODE = 1;
82
83 /**
84 * A flag to skip the SourceFile, SourceDebugExtension, LocalVariableTable,
85 * LocalVariableTypeTable, LineNumberTable and MethodParameters attributes. If this flag is set
86 * these attributes are neither parsed nor visited (i.e. {@link ClassVisitor#visitSource}, {@link
87 * MethodVisitor#visitLocalVariable}, {@link MethodVisitor#visitLineNumber} and {@link
88 * MethodVisitor#visitParameter} are not called).
89 */
90 public static final int SKIP_DEBUG = 2;
91
92 /**
93 * A flag to skip the StackMap and StackMapTable attributes. If this flag is set these attributes
94 * are neither parsed nor visited (i.e. {@link MethodVisitor#visitFrame} is not called). This flag
95 * is useful when the {@link ClassWriter#COMPUTE_FRAMES} option is used: it avoids visiting frames
96 * that will be ignored and recomputed from scratch.
97 */
98 public static final int SKIP_FRAMES = 4;
99
100 /**
101 * A flag to expand the stack map frames. By default stack map frames are visited in their
102 * original format (i.e. "expanded" for classes whose version is less than V1_6, and "compressed"
103 * for the other classes). If this flag is set, stack map frames are always visited in expanded
104 * format (this option adds a decompression/compression step in ClassReader and ClassWriter which
105 * degrades performance quite a lot).
106 */
107 public static final int EXPAND_FRAMES = 8;
108
109 /**
110 * A flag to expand the ASM specific instructions into an equivalent sequence of standard bytecode
111 * instructions. When resolving a forward jump it may happen that the signed 2 bytes offset
112 * reserved for it is not sufficient to store the bytecode offset. In this case the jump
113 * instruction is replaced with a temporary ASM specific instruction using an unsigned 2 bytes
114 * offset (see {@link Label#resolve}). This internal flag is used to re-read classes containing
115 * such instructions, in order to replace them with standard instructions. In addition, when this
116 * flag is used, goto_w and jsr_w are <i>not</i> converted into goto and jsr, to make sure that
117 * infinite loops where a goto_w is replaced with a goto in ClassReader and converted back to a
118 * goto_w in ClassWriter cannot occur.
119 */
120 static final int EXPAND_ASM_INSNS = 256;
121
122 /** The size of the temporary byte array used to read class input streams chunk by chunk. */
123 private static final int INPUT_STREAM_DATA_CHUNK_SIZE = 4096;
124
125 /**
126 * A byte array containing the JVMS ClassFile structure to be parsed.
127 *
128 * @deprecated Use {@link #readByte(int)} and the other read methods instead. This field will
129 * eventually be deleted.
130 */
131 @Deprecated
132 // DontCheck(MemberName): can't be renamed (for backward binary compatibility).
133 public final byte[] b;
134
135 /**
136 * A byte array containing the JVMS ClassFile structure to be parsed. <i>The content of this array
137 * must not be modified. This field is intended for {@link Attribute} sub classes, and is normally
138 * not needed by class visitors.</i>
139 *
140 * <p>NOTE: the ClassFile structure can start at any offset within this array, i.e. it does not
141 * necessarily start at offset 0. Use {@link #getItem} and {@link #header} to get correct
142 * ClassFile element offsets within this byte array.
143 */
144 final byte[] classFileBuffer;
145
146 /**
147 * The offset in bytes, in {@link #classFileBuffer}, of each cp_info entry of the ClassFile's
148 * constant_pool array, <i>plus one</i>. In other words, the offset of constant pool entry i is
149 * given by cpInfoOffsets[i] - 1, i.e. its cp_info's tag field is given by b[cpInfoOffsets[i] -
150 * 1].
151 */
152 private final int[] cpInfoOffsets;
153
154 /**
155 * The String objects corresponding to the CONSTANT_Utf8 constant pool items. This cache avoids
156 * multiple parsing of a given CONSTANT_Utf8 constant pool item.
157 */
158 private final String[] constantUtf8Values;
159
160 /**
161 * The ConstantDynamic objects corresponding to the CONSTANT_Dynamic constant pool items. This
162 * cache avoids multiple parsing of a given CONSTANT_Dynamic constant pool item.
163 */
164 private final ConstantDynamic[] constantDynamicValues;
165
166 /**
167 * The start offsets in {@link #classFileBuffer} of each element of the bootstrap_methods array
168 * (in the BootstrapMethods attribute).
169 *
170 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.23">JVMS
171 * 4.7.23</a>
172 */
173 private final int[] bootstrapMethodOffsets;
174
175 /**
176 * A conservative estimate of the maximum length of the strings contained in the constant pool of
177 * the class.
178 */
179 private final int maxStringLength;
180
181 /** The offset in bytes of the ClassFile's access_flags field. */
182 public final int header;
183
184 // -----------------------------------------------------------------------------------------------
185 // Constructors
186 // -----------------------------------------------------------------------------------------------
187
188 /**
189 * Constructs a new {@link ClassReader} object.
190 *
191 * @param classFile the JVMS ClassFile structure to be read.
192 */
193 public ClassReader(final byte[] classFile) {
194 this(classFile, 0, classFile.length);
195 }
196
197 /**
198 * Constructs a new {@link ClassReader} object.
199 *
200 * @param classFileBuffer a byte array containing the JVMS ClassFile structure to be read.
201 * @param classFileOffset the offset in byteBuffer of the first byte of the ClassFile to be read.
202 * @param classFileLength the length in bytes of the ClassFile to be read.
203 */
204 public ClassReader(
205 final byte[] classFileBuffer,
206 final int classFileOffset,
207 final int classFileLength) { // NOPMD(UnusedFormalParameter) used for backward compatibility.
208 this(classFileBuffer, classFileOffset, /* checkClassVersion = */ true);
209 }
210
211 /**
212 * Constructs a new {@link ClassReader} object. <i>This internal constructor must not be exposed
213 * as a public API</i>.
214 *
215 * @param classFileBuffer a byte array containing the JVMS ClassFile structure to be read.
216 * @param classFileOffset the offset in byteBuffer of the first byte of the ClassFile to be read.
217 * @param checkClassVersion whether to check the class version or not.
218 */
219 ClassReader(
220 final byte[] classFileBuffer, final int classFileOffset, final boolean checkClassVersion) {
221 this.classFileBuffer = classFileBuffer;
222 this.b = classFileBuffer;
223 // Check the class' major_version. This field is after the magic and minor_version fields, which
224 // use 4 and 2 bytes respectively.
225 if (checkClassVersion && readShort(classFileOffset + 6) > Opcodes.V18) {
226 throw new IllegalArgumentException(
227 "Unsupported class file major version " + readShort(classFileOffset + 6));
228 }
229 // Create the constant pool arrays. The constant_pool_count field is after the magic,
230 // minor_version and major_version fields, which use 4, 2 and 2 bytes respectively.
231 int constantPoolCount = readUnsignedShort(classFileOffset + 8);
232 cpInfoOffsets = new int[constantPoolCount];
233 constantUtf8Values = new String[constantPoolCount];
234 // Compute the offset of each constant pool entry, as well as a conservative estimate of the
235 // maximum length of the constant pool strings. The first constant pool entry is after the
236 // magic, minor_version, major_version and constant_pool_count fields, which use 4, 2, 2 and 2
237 // bytes respectively.
238 int currentCpInfoIndex = 1;
239 int currentCpInfoOffset = classFileOffset + 10;
240 int currentMaxStringLength = 0;
241 boolean hasBootstrapMethods = false;
242 boolean hasConstantDynamic = false;
243 // The offset of the other entries depend on the total size of all the previous entries.
244 while (currentCpInfoIndex < constantPoolCount) {
245 cpInfoOffsets[currentCpInfoIndex++] = currentCpInfoOffset + 1;
246 int cpInfoSize;
247 switch (classFileBuffer[currentCpInfoOffset]) {
248 case Symbol.CONSTANT_FIELDREF_TAG:
249 case Symbol.CONSTANT_METHODREF_TAG:
250 case Symbol.CONSTANT_INTERFACE_METHODREF_TAG:
251 case Symbol.CONSTANT_INTEGER_TAG:
252 case Symbol.CONSTANT_FLOAT_TAG:
253 case Symbol.CONSTANT_NAME_AND_TYPE_TAG:
254 cpInfoSize = 5;
255 break;
256 case Symbol.CONSTANT_DYNAMIC_TAG:
257 cpInfoSize = 5;
258 hasBootstrapMethods = true;
259 hasConstantDynamic = true;
260 break;
261 case Symbol.CONSTANT_INVOKE_DYNAMIC_TAG:
262 cpInfoSize = 5;
263 hasBootstrapMethods = true;
264 break;
265 case Symbol.CONSTANT_LONG_TAG:
266 case Symbol.CONSTANT_DOUBLE_TAG:
267 cpInfoSize = 9;
268 currentCpInfoIndex++;
269 break;
270 case Symbol.CONSTANT_UTF8_TAG:
271 cpInfoSize = 3 + readUnsignedShort(currentCpInfoOffset + 1);
272 if (cpInfoSize > currentMaxStringLength) {
273 // The size in bytes of this CONSTANT_Utf8 structure provides a conservative estimate
274 // of the length in characters of the corresponding string, and is much cheaper to
275 // compute than this exact length.
276 currentMaxStringLength = cpInfoSize;
277 }
278 break;
279 case Symbol.CONSTANT_METHOD_HANDLE_TAG:
280 cpInfoSize = 4;
281 break;
282 case Symbol.CONSTANT_CLASS_TAG:
283 case Symbol.CONSTANT_STRING_TAG:
284 case Symbol.CONSTANT_METHOD_TYPE_TAG:
285 case Symbol.CONSTANT_PACKAGE_TAG:
286 case Symbol.CONSTANT_MODULE_TAG:
287 cpInfoSize = 3;
288 break;
289 default:
290 throw new IllegalArgumentException();
291 }
292 currentCpInfoOffset += cpInfoSize;
293 }
294 maxStringLength = currentMaxStringLength;
295 // The Classfile's access_flags field is just after the last constant pool entry.
296 header = currentCpInfoOffset;
297
298 // Allocate the cache of ConstantDynamic values, if there is at least one.
299 constantDynamicValues = hasConstantDynamic ? new ConstantDynamic[constantPoolCount] : null;
300
301 // Read the BootstrapMethods attribute, if any (only get the offset of each method).
302 bootstrapMethodOffsets =
303 hasBootstrapMethods ? readBootstrapMethodsAttribute(currentMaxStringLength) : null;
304 }
305
306 /**
307 * Constructs a new {@link ClassReader} object.
308 *
309 * @param inputStream an input stream of the JVMS ClassFile structure to be read. This input
310 * stream must contain nothing more than the ClassFile structure itself. It is read from its
311 * current position to its end.
312 * @throws IOException if a problem occurs during reading.
313 */
314 public ClassReader(final InputStream inputStream) throws IOException {
315 this(readStream(inputStream, false));
316 }
317
318 /**
319 * Constructs a new {@link ClassReader} object.
320 *
321 * @param className the fully qualified name of the class to be read. The ClassFile structure is
322 * retrieved with the current class loader's {@link ClassLoader#getSystemResourceAsStream}.
323 * @throws IOException if an exception occurs during reading.
324 */
325 public ClassReader(final String className) throws IOException {
326 this(
327 readStream(
328 ClassLoader.getSystemResourceAsStream(className.replace('.', '/') + ".class"), true));
329 }
330
331 /**
332 * Reads the given input stream and returns its content as a byte array.
333 *
334 * @param inputStream an input stream.
335 * @param close true to close the input stream after reading.
336 * @return the content of the given input stream.
337 * @throws IOException if a problem occurs during reading.
338 */
339 private static byte[] readStream(final InputStream inputStream, final boolean close)
340 throws IOException {
341 if (inputStream == null) {
342 throw new IOException("Class not found");
343 }
344 try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
345 byte[] data = new byte[INPUT_STREAM_DATA_CHUNK_SIZE];
346 int bytesRead;
347 while ((bytesRead = inputStream.read(data, 0, data.length)) != -1) {
348 outputStream.write(data, 0, bytesRead);
349 }
350 outputStream.flush();
351 return outputStream.toByteArray();
352 } finally {
353 if (close) {
354 inputStream.close();
355 }
356 }
357 }
358
359 // -----------------------------------------------------------------------------------------------
360 // Accessors
361 // -----------------------------------------------------------------------------------------------
362
363 /**
364 * Returns the class's access flags (see {@link Opcodes}). This value may not reflect Deprecated
365 * and Synthetic flags when bytecode is before 1.5 and those flags are represented by attributes.
366 *
367 * @return the class access flags.
368 * @see ClassVisitor#visit(int, int, String, String, String, String[])
369 */
370 public int getAccess() {
371 return readUnsignedShort(header);
372 }
373
374 /**
375 * Returns the internal name of the class (see {@link Type#getInternalName()}).
376 *
377 * @return the internal class name.
378 * @see ClassVisitor#visit(int, int, String, String, String, String[])
379 */
380 public String getClassName() {
381 // this_class is just after the access_flags field (using 2 bytes).
382 return readClass(header + 2, new char[maxStringLength]);
383 }
384
385 /**
386 * Returns the internal of name of the super class (see {@link Type#getInternalName()}). For
387 * interfaces, the super class is {@link Object}.
388 *
389 * @return the internal name of the super class, or {@literal null} for {@link Object} class.
390 * @see ClassVisitor#visit(int, int, String, String, String, String[])
391 */
392 public String getSuperName() {
393 // super_class is after the access_flags and this_class fields (2 bytes each).
394 return readClass(header + 4, new char[maxStringLength]);
395 }
396
397 /**
398 * Returns the internal names of the implemented interfaces (see {@link Type#getInternalName()}).
399 *
400 * @return the internal names of the directly implemented interfaces. Inherited implemented
401 * interfaces are not returned.
402 * @see ClassVisitor#visit(int, int, String, String, String, String[])
403 */
404 public String[] getInterfaces() {
405 // interfaces_count is after the access_flags, this_class and super_class fields (2 bytes each).
406 int currentOffset = header + 6;
407 int interfacesCount = readUnsignedShort(currentOffset);
408 String[] interfaces = new String[interfacesCount];
409 if (interfacesCount > 0) {
410 char[] charBuffer = new char[maxStringLength];
411 for (int i = 0; i < interfacesCount; ++i) {
412 currentOffset += 2;
413 interfaces[i] = readClass(currentOffset, charBuffer);
414 }
415 }
416 return interfaces;
417 }
418
419 // -----------------------------------------------------------------------------------------------
420 // Public methods
421 // -----------------------------------------------------------------------------------------------
422
423 /**
424 * Makes the given visitor visit the JVMS ClassFile structure passed to the constructor of this
425 * {@link ClassReader}.
426 *
427 * @param classVisitor the visitor that must visit this class.
428 * @param parsingOptions the options to use to parse this class. One or more of {@link
429 * #SKIP_CODE}, {@link #SKIP_DEBUG}, {@link #SKIP_FRAMES} or {@link #EXPAND_FRAMES}.
430 */
431 public void accept(final ClassVisitor classVisitor, final int parsingOptions) {
432 accept(classVisitor, new Attribute[0], parsingOptions);
433 }
434
435 /**
436 * Makes the given visitor visit the JVMS ClassFile structure passed to the constructor of this
437 * {@link ClassReader}.
438 *
439 * @param classVisitor the visitor that must visit this class.
440 * @param attributePrototypes prototypes of the attributes that must be parsed during the visit of
441 * the class. Any attribute whose type is not equal to the type of one the prototypes will not
442 * be parsed: its byte array value will be passed unchanged to the ClassWriter. <i>This may
443 * corrupt it if this value contains references to the constant pool, or has syntactic or
444 * semantic links with a class element that has been transformed by a class adapter between
445 * the reader and the writer</i>.
446 * @param parsingOptions the options to use to parse this class. One or more of {@link
447 * #SKIP_CODE}, {@link #SKIP_DEBUG}, {@link #SKIP_FRAMES} or {@link #EXPAND_FRAMES}.
448 */
449 @SuppressWarnings("deprecation")
450 public void accept(
451 final ClassVisitor classVisitor,
452 final Attribute[] attributePrototypes,
453 final int parsingOptions) {
454 Context context = new Context();
455 context.attributePrototypes = attributePrototypes;
456 context.parsingOptions = parsingOptions;
457 context.charBuffer = new char[maxStringLength];
458
459 // Read the access_flags, this_class, super_class, interface_count and interfaces fields.
460 char[] charBuffer = context.charBuffer;
461 int currentOffset = header;
462 int accessFlags = readUnsignedShort(currentOffset);
463 String thisClass = readClass(currentOffset + 2, charBuffer);
464 String superClass = readClass(currentOffset + 4, charBuffer);
465 String[] interfaces = new String[readUnsignedShort(currentOffset + 6)];
466 currentOffset += 8;
467 for (int i = 0; i < interfaces.length; ++i) {
468 interfaces[i] = readClass(currentOffset, charBuffer);
469 currentOffset += 2;
470 }
471
472 // Read the class attributes (the variables are ordered as in Section 4.7 of the JVMS).
473 // Attribute offsets exclude the attribute_name_index and attribute_length fields.
474 // - The offset of the InnerClasses attribute, or 0.
475 int innerClassesOffset = 0;
476 // - The offset of the EnclosingMethod attribute, or 0.
477 int enclosingMethodOffset = 0;
478 // - The string corresponding to the Signature attribute, or null.
479 String signature = null;
480 // - The string corresponding to the SourceFile attribute, or null.
481 String sourceFile = null;
482 // - The string corresponding to the SourceDebugExtension attribute, or null.
483 String sourceDebugExtension = null;
484 // - The offset of the RuntimeVisibleAnnotations attribute, or 0.
485 int runtimeVisibleAnnotationsOffset = 0;
486 // - The offset of the RuntimeInvisibleAnnotations attribute, or 0.
487 int runtimeInvisibleAnnotationsOffset = 0;
488 // - The offset of the RuntimeVisibleTypeAnnotations attribute, or 0.
489 int runtimeVisibleTypeAnnotationsOffset = 0;
490 // - The offset of the RuntimeInvisibleTypeAnnotations attribute, or 0.
491 int runtimeInvisibleTypeAnnotationsOffset = 0;
492 // - The offset of the Module attribute, or 0.
493 int moduleOffset = 0;
494 // - The offset of the ModulePackages attribute, or 0.
495 int modulePackagesOffset = 0;
496 // - The string corresponding to the ModuleMainClass attribute, or null.
497 String moduleMainClass = null;
498 // - The string corresponding to the NestHost attribute, or null.
499 String nestHostClass = null;
500 // - The offset of the NestMembers attribute, or 0.
501 int nestMembersOffset = 0;
502 // - The offset of the PermittedSubclasses attribute, or 0
503 int permittedSubclassesOffset = 0;
504 // - The offset of the Record attribute, or 0.
505 int recordOffset = 0;
506 // - The non standard attributes (linked with their {@link Attribute#nextAttribute} field).
507 // This list in the <i>reverse order</i> or their order in the ClassFile structure.
508 Attribute attributes = null;
509
510 int currentAttributeOffset = getFirstAttributeOffset();
511 for (int i = readUnsignedShort(currentAttributeOffset - 2); i > 0; --i) {
512 // Read the attribute_info's attribute_name and attribute_length fields.
513 String attributeName = readUTF8(currentAttributeOffset, charBuffer);
514 int attributeLength = readInt(currentAttributeOffset + 2);
515 currentAttributeOffset += 6;
516 // The tests are sorted in decreasing frequency order (based on frequencies observed on
517 // typical classes).
518 if (Constants.SOURCE_FILE.equals(attributeName)) {
519 sourceFile = readUTF8(currentAttributeOffset, charBuffer);
520 } else if (Constants.INNER_CLASSES.equals(attributeName)) {
521 innerClassesOffset = currentAttributeOffset;
522 } else if (Constants.ENCLOSING_METHOD.equals(attributeName)) {
523 enclosingMethodOffset = currentAttributeOffset;
524 } else if (Constants.NEST_HOST.equals(attributeName)) {
525 nestHostClass = readClass(currentAttributeOffset, charBuffer);
526 } else if (Constants.NEST_MEMBERS.equals(attributeName)) {
527 nestMembersOffset = currentAttributeOffset;
528 } else if (Constants.PERMITTED_SUBCLASSES.equals(attributeName)) {
529 permittedSubclassesOffset = currentAttributeOffset;
530 } else if (Constants.SIGNATURE.equals(attributeName)) {
531 signature = readUTF8(currentAttributeOffset, charBuffer);
532 } else if (Constants.RUNTIME_VISIBLE_ANNOTATIONS.equals(attributeName)) {
533 runtimeVisibleAnnotationsOffset = currentAttributeOffset;
534 } else if (Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
535 runtimeVisibleTypeAnnotationsOffset = currentAttributeOffset;
536 } else if (Constants.DEPRECATED.equals(attributeName)) {
537 accessFlags |= Opcodes.ACC_DEPRECATED;
538 } else if (Constants.SYNTHETIC.equals(attributeName)) {
539 accessFlags |= Opcodes.ACC_SYNTHETIC;
540 } else if (Constants.SOURCE_DEBUG_EXTENSION.equals(attributeName)) {
541 if (attributeLength > classFileBuffer.length - currentAttributeOffset) {
542 throw new IllegalArgumentException();
543 }
544 sourceDebugExtension =
545 readUtf(currentAttributeOffset, attributeLength, new char[attributeLength]);
546 } else if (Constants.RUNTIME_INVISIBLE_ANNOTATIONS.equals(attributeName)) {
547 runtimeInvisibleAnnotationsOffset = currentAttributeOffset;
548 } else if (Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
549 runtimeInvisibleTypeAnnotationsOffset = currentAttributeOffset;
550 } else if (Constants.RECORD.equals(attributeName)) {
551 recordOffset = currentAttributeOffset;
552 accessFlags |= Opcodes.ACC_RECORD;
553 } else if (Constants.MODULE.equals(attributeName)) {
554 moduleOffset = currentAttributeOffset;
555 } else if (Constants.MODULE_MAIN_CLASS.equals(attributeName)) {
556 moduleMainClass = readClass(currentAttributeOffset, charBuffer);
557 } else if (Constants.MODULE_PACKAGES.equals(attributeName)) {
558 modulePackagesOffset = currentAttributeOffset;
559 } else if (!Constants.BOOTSTRAP_METHODS.equals(attributeName)) {
560 // The BootstrapMethods attribute is read in the constructor.
561 Attribute attribute =
562 readAttribute(
563 attributePrototypes,
564 attributeName,
565 currentAttributeOffset,
566 attributeLength,
567 charBuffer,
568 -1,
569 null);
570 attribute.nextAttribute = attributes;
571 attributes = attribute;
572 }
573 currentAttributeOffset += attributeLength;
574 }
575
576 // Visit the class declaration. The minor_version and major_version fields start 6 bytes before
577 // the first constant pool entry, which itself starts at cpInfoOffsets[1] - 1 (by definition).
578 classVisitor.visit(
579 readInt(cpInfoOffsets[1] - 7), accessFlags, thisClass, signature, superClass, interfaces);
580
581 // Visit the SourceFile and SourceDebugExtenstion attributes.
582 if ((parsingOptions & SKIP_DEBUG) == 0
583 && (sourceFile != null || sourceDebugExtension != null)) {
584 classVisitor.visitSource(sourceFile, sourceDebugExtension);
585 }
586
587 // Visit the Module, ModulePackages and ModuleMainClass attributes.
588 if (moduleOffset != 0) {
589 readModuleAttributes(
590 classVisitor, context, moduleOffset, modulePackagesOffset, moduleMainClass);
591 }
592
593 // Visit the NestHost attribute.
594 if (nestHostClass != null) {
595 classVisitor.visitNestHost(nestHostClass);
596 }
597
598 // Visit the EnclosingMethod attribute.
599 if (enclosingMethodOffset != 0) {
600 String className = readClass(enclosingMethodOffset, charBuffer);
601 int methodIndex = readUnsignedShort(enclosingMethodOffset + 2);
602 String name = methodIndex == 0 ? null : readUTF8(cpInfoOffsets[methodIndex], charBuffer);
603 String type = methodIndex == 0 ? null : readUTF8(cpInfoOffsets[methodIndex] + 2, charBuffer);
604 classVisitor.visitOuterClass(className, name, type);
605 }
606
607 // Visit the RuntimeVisibleAnnotations attribute.
608 if (runtimeVisibleAnnotationsOffset != 0) {
609 int numAnnotations = readUnsignedShort(runtimeVisibleAnnotationsOffset);
610 int currentAnnotationOffset = runtimeVisibleAnnotationsOffset + 2;
611 while (numAnnotations-- > 0) {
612 // Parse the type_index field.
613 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
614 currentAnnotationOffset += 2;
615 // Parse num_element_value_pairs and element_value_pairs and visit these values.
616 currentAnnotationOffset =
617 readElementValues(
618 classVisitor.visitAnnotation(annotationDescriptor, /* visible = */ true),
619 currentAnnotationOffset,
620 /* named = */ true,
621 charBuffer);
622 }
623 }
624
625 // Visit the RuntimeInvisibleAnnotations attribute.
626 if (runtimeInvisibleAnnotationsOffset != 0) {
627 int numAnnotations = readUnsignedShort(runtimeInvisibleAnnotationsOffset);
628 int currentAnnotationOffset = runtimeInvisibleAnnotationsOffset + 2;
629 while (numAnnotations-- > 0) {
630 // Parse the type_index field.
631 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
632 currentAnnotationOffset += 2;
633 // Parse num_element_value_pairs and element_value_pairs and visit these values.
634 currentAnnotationOffset =
635 readElementValues(
636 classVisitor.visitAnnotation(annotationDescriptor, /* visible = */ false),
637 currentAnnotationOffset,
638 /* named = */ true,
639 charBuffer);
640 }
641 }
642
643 // Visit the RuntimeVisibleTypeAnnotations attribute.
644 if (runtimeVisibleTypeAnnotationsOffset != 0) {
645 int numAnnotations = readUnsignedShort(runtimeVisibleTypeAnnotationsOffset);
646 int currentAnnotationOffset = runtimeVisibleTypeAnnotationsOffset + 2;
647 while (numAnnotations-- > 0) {
648 // Parse the target_type, target_info and target_path fields.
649 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
650 // Parse the type_index field.
651 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
652 currentAnnotationOffset += 2;
653 // Parse num_element_value_pairs and element_value_pairs and visit these values.
654 currentAnnotationOffset =
655 readElementValues(
656 classVisitor.visitTypeAnnotation(
657 context.currentTypeAnnotationTarget,
658 context.currentTypeAnnotationTargetPath,
659 annotationDescriptor,
660 /* visible = */ true),
661 currentAnnotationOffset,
662 /* named = */ true,
663 charBuffer);
664 }
665 }
666
667 // Visit the RuntimeInvisibleTypeAnnotations attribute.
668 if (runtimeInvisibleTypeAnnotationsOffset != 0) {
669 int numAnnotations = readUnsignedShort(runtimeInvisibleTypeAnnotationsOffset);
670 int currentAnnotationOffset = runtimeInvisibleTypeAnnotationsOffset + 2;
671 while (numAnnotations-- > 0) {
672 // Parse the target_type, target_info and target_path fields.
673 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
674 // Parse the type_index field.
675 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
676 currentAnnotationOffset += 2;
677 // Parse num_element_value_pairs and element_value_pairs and visit these values.
678 currentAnnotationOffset =
679 readElementValues(
680 classVisitor.visitTypeAnnotation(
681 context.currentTypeAnnotationTarget,
682 context.currentTypeAnnotationTargetPath,
683 annotationDescriptor,
684 /* visible = */ false),
685 currentAnnotationOffset,
686 /* named = */ true,
687 charBuffer);
688 }
689 }
690
691 // Visit the non standard attributes.
692 while (attributes != null) {
693 // Copy and reset the nextAttribute field so that it can also be used in ClassWriter.
694 Attribute nextAttribute = attributes.nextAttribute;
695 attributes.nextAttribute = null;
696 classVisitor.visitAttribute(attributes);
697 attributes = nextAttribute;
698 }
699
700 // Visit the NestedMembers attribute.
701 if (nestMembersOffset != 0) {
702 int numberOfNestMembers = readUnsignedShort(nestMembersOffset);
703 int currentNestMemberOffset = nestMembersOffset + 2;
704 while (numberOfNestMembers-- > 0) {
705 classVisitor.visitNestMember(readClass(currentNestMemberOffset, charBuffer));
706 currentNestMemberOffset += 2;
707 }
708 }
709
710 // Visit the PermittedSubclasses attribute.
711 if (permittedSubclassesOffset != 0) {
712 int numberOfPermittedSubclasses = readUnsignedShort(permittedSubclassesOffset);
713 int currentPermittedSubclassOffset = permittedSubclassesOffset + 2;
714 while (numberOfPermittedSubclasses-- > 0) {
715 classVisitor.visitPermittedSubclassExperimental(
716 readClass(currentPermittedSubclassOffset, charBuffer));
717 currentPermittedSubclassOffset += 2;
718 }
719 }
720
721 // Visit the InnerClasses attribute.
722 if (innerClassesOffset != 0) {
723 int numberOfClasses = readUnsignedShort(innerClassesOffset);
724 int currentClassesOffset = innerClassesOffset + 2;
725 while (numberOfClasses-- > 0) {
726 classVisitor.visitInnerClass(
727 readClass(currentClassesOffset, charBuffer),
728 readClass(currentClassesOffset + 2, charBuffer),
729 readUTF8(currentClassesOffset + 4, charBuffer),
730 readUnsignedShort(currentClassesOffset + 6));
731 currentClassesOffset += 8;
732 }
733 }
734
735 // Visit Record components.
736 if (recordOffset != 0) {
737 int recordComponentsCount = readUnsignedShort(recordOffset);
738 recordOffset += 2;
739 while (recordComponentsCount-- > 0) {
740 recordOffset = readRecordComponent(classVisitor, context, recordOffset);
741 }
742 }
743
744 // Visit the fields and methods.
745 int fieldsCount = readUnsignedShort(currentOffset);
746 currentOffset += 2;
747 while (fieldsCount-- > 0) {
748 currentOffset = readField(classVisitor, context, currentOffset);
749 }
750 int methodsCount = readUnsignedShort(currentOffset);
751 currentOffset += 2;
752 while (methodsCount-- > 0) {
753 currentOffset = readMethod(classVisitor, context, currentOffset);
754 }
755
756 // Visit the end of the class.
757 classVisitor.visitEnd();
758 }
759
760 // ----------------------------------------------------------------------------------------------
761 // Methods to parse modules, fields and methods
762 // ----------------------------------------------------------------------------------------------
763
764 /**
765 * Reads the Module, ModulePackages and ModuleMainClass attributes and visit them.
766 *
767 * @param classVisitor the current class visitor
768 * @param context information about the class being parsed.
769 * @param moduleOffset the offset of the Module attribute (excluding the attribute_info's
770 * attribute_name_index and attribute_length fields).
771 * @param modulePackagesOffset the offset of the ModulePackages attribute (excluding the
772 * attribute_info's attribute_name_index and attribute_length fields), or 0.
773 * @param moduleMainClass the string corresponding to the ModuleMainClass attribute, or {@literal
774 * null}.
775 */
776 private void readModuleAttributes(
777 final ClassVisitor classVisitor,
778 final Context context,
779 final int moduleOffset,
780 final int modulePackagesOffset,
781 final String moduleMainClass) {
782 char[] buffer = context.charBuffer;
783
784 // Read the module_name_index, module_flags and module_version_index fields and visit them.
785 int currentOffset = moduleOffset;
786 String moduleName = readModule(currentOffset, buffer);
787 int moduleFlags = readUnsignedShort(currentOffset + 2);
788 String moduleVersion = readUTF8(currentOffset + 4, buffer);
789 currentOffset += 6;
790 ModuleVisitor moduleVisitor = classVisitor.visitModule(moduleName, moduleFlags, moduleVersion);
791 if (moduleVisitor == null) {
792 return;
793 }
794
795 // Visit the ModuleMainClass attribute.
796 if (moduleMainClass != null) {
797 moduleVisitor.visitMainClass(moduleMainClass);
798 }
799
800 // Visit the ModulePackages attribute.
801 if (modulePackagesOffset != 0) {
802 int packageCount = readUnsignedShort(modulePackagesOffset);
803 int currentPackageOffset = modulePackagesOffset + 2;
804 while (packageCount-- > 0) {
805 moduleVisitor.visitPackage(readPackage(currentPackageOffset, buffer));
806 currentPackageOffset += 2;
807 }
808 }
809
810 // Read the 'requires_count' and 'requires' fields.
811 int requiresCount = readUnsignedShort(currentOffset);
812 currentOffset += 2;
813 while (requiresCount-- > 0) {
814 // Read the requires_index, requires_flags and requires_version fields and visit them.
815 String requires = readModule(currentOffset, buffer);
816 int requiresFlags = readUnsignedShort(currentOffset + 2);
817 String requiresVersion = readUTF8(currentOffset + 4, buffer);
818 currentOffset += 6;
819 moduleVisitor.visitRequire(requires, requiresFlags, requiresVersion);
820 }
821
822 // Read the 'exports_count' and 'exports' fields.
823 int exportsCount = readUnsignedShort(currentOffset);
824 currentOffset += 2;
825 while (exportsCount-- > 0) {
826 // Read the exports_index, exports_flags, exports_to_count and exports_to_index fields
827 // and visit them.
828 String exports = readPackage(currentOffset, buffer);
829 int exportsFlags = readUnsignedShort(currentOffset + 2);
830 int exportsToCount = readUnsignedShort(currentOffset + 4);
831 currentOffset += 6;
832 String[] exportsTo = null;
833 if (exportsToCount != 0) {
834 exportsTo = new String[exportsToCount];
835 for (int i = 0; i < exportsToCount; ++i) {
836 exportsTo[i] = readModule(currentOffset, buffer);
837 currentOffset += 2;
838 }
839 }
840 moduleVisitor.visitExport(exports, exportsFlags, exportsTo);
841 }
842
843 // Reads the 'opens_count' and 'opens' fields.
844 int opensCount = readUnsignedShort(currentOffset);
845 currentOffset += 2;
846 while (opensCount-- > 0) {
847 // Read the opens_index, opens_flags, opens_to_count and opens_to_index fields and visit them.
848 String opens = readPackage(currentOffset, buffer);
849 int opensFlags = readUnsignedShort(currentOffset + 2);
850 int opensToCount = readUnsignedShort(currentOffset + 4);
851 currentOffset += 6;
852 String[] opensTo = null;
853 if (opensToCount != 0) {
854 opensTo = new String[opensToCount];
855 for (int i = 0; i < opensToCount; ++i) {
856 opensTo[i] = readModule(currentOffset, buffer);
857 currentOffset += 2;
858 }
859 }
860 moduleVisitor.visitOpen(opens, opensFlags, opensTo);
861 }
862
863 // Read the 'uses_count' and 'uses' fields.
864 int usesCount = readUnsignedShort(currentOffset);
865 currentOffset += 2;
866 while (usesCount-- > 0) {
867 moduleVisitor.visitUse(readClass(currentOffset, buffer));
868 currentOffset += 2;
869 }
870
871 // Read the 'provides_count' and 'provides' fields.
872 int providesCount = readUnsignedShort(currentOffset);
873 currentOffset += 2;
874 while (providesCount-- > 0) {
875 // Read the provides_index, provides_with_count and provides_with_index fields and visit them.
876 String provides = readClass(currentOffset, buffer);
877 int providesWithCount = readUnsignedShort(currentOffset + 2);
878 currentOffset += 4;
879 String[] providesWith = new String[providesWithCount];
880 for (int i = 0; i < providesWithCount; ++i) {
881 providesWith[i] = readClass(currentOffset, buffer);
882 currentOffset += 2;
883 }
884 moduleVisitor.visitProvide(provides, providesWith);
885 }
886
887 // Visit the end of the module attributes.
888 moduleVisitor.visitEnd();
889 }
890
891 /**
892 * Reads a record component and visit it.
893 *
894 * @param classVisitor the current class visitor
895 * @param context information about the class being parsed.
896 * @param recordComponentOffset the offset of the current record component.
897 * @return the offset of the first byte following the record component.
898 */
899 private int readRecordComponent(
900 final ClassVisitor classVisitor, final Context context, final int recordComponentOffset) {
901 char[] charBuffer = context.charBuffer;
902
903 int currentOffset = recordComponentOffset;
904 String name = readUTF8(currentOffset, charBuffer);
905 String descriptor = readUTF8(currentOffset + 2, charBuffer);
906 currentOffset += 4;
907
908 // Read the record component attributes (the variables are ordered as in Section 4.7 of the
909 // JVMS).
910
911 // Attribute offsets exclude the attribute_name_index and attribute_length fields.
912 // - The string corresponding to the Signature attribute, or null.
913 String signature = null;
914 // - The offset of the RuntimeVisibleAnnotations attribute, or 0.
915 int runtimeVisibleAnnotationsOffset = 0;
916 // - The offset of the RuntimeInvisibleAnnotations attribute, or 0.
917 int runtimeInvisibleAnnotationsOffset = 0;
918 // - The offset of the RuntimeVisibleTypeAnnotations attribute, or 0.
919 int runtimeVisibleTypeAnnotationsOffset = 0;
920 // - The offset of the RuntimeInvisibleTypeAnnotations attribute, or 0.
921 int runtimeInvisibleTypeAnnotationsOffset = 0;
922 // - The non standard attributes (linked with their {@link Attribute#nextAttribute} field).
923 // This list in the <i>reverse order</i> or their order in the ClassFile structure.
924 Attribute attributes = null;
925
926 int attributesCount = readUnsignedShort(currentOffset);
927 currentOffset += 2;
928 while (attributesCount-- > 0) {
929 // Read the attribute_info's attribute_name and attribute_length fields.
930 String attributeName = readUTF8(currentOffset, charBuffer);
931 int attributeLength = readInt(currentOffset + 2);
932 currentOffset += 6;
933 // The tests are sorted in decreasing frequency order (based on frequencies observed on
934 // typical classes).
935 if (Constants.SIGNATURE.equals(attributeName)) {
936 signature = readUTF8(currentOffset, charBuffer);
937 } else if (Constants.RUNTIME_VISIBLE_ANNOTATIONS.equals(attributeName)) {
938 runtimeVisibleAnnotationsOffset = currentOffset;
939 } else if (Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
940 runtimeVisibleTypeAnnotationsOffset = currentOffset;
941 } else if (Constants.RUNTIME_INVISIBLE_ANNOTATIONS.equals(attributeName)) {
942 runtimeInvisibleAnnotationsOffset = currentOffset;
943 } else if (Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
944 runtimeInvisibleTypeAnnotationsOffset = currentOffset;
945 } else {
946 Attribute attribute =
947 readAttribute(
948 context.attributePrototypes,
949 attributeName,
950 currentOffset,
951 attributeLength,
952 charBuffer,
953 -1,
954 null);
955 attribute.nextAttribute = attributes;
956 attributes = attribute;
957 }
958 currentOffset += attributeLength;
959 }
960
961 RecordComponentVisitor recordComponentVisitor =
962 classVisitor.visitRecordComponent(name, descriptor, signature);
963 if (recordComponentVisitor == null) {
964 return currentOffset;
965 }
966
967 // Visit the RuntimeVisibleAnnotations attribute.
968 if (runtimeVisibleAnnotationsOffset != 0) {
969 int numAnnotations = readUnsignedShort(runtimeVisibleAnnotationsOffset);
970 int currentAnnotationOffset = runtimeVisibleAnnotationsOffset + 2;
971 while (numAnnotations-- > 0) {
972 // Parse the type_index field.
973 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
974 currentAnnotationOffset += 2;
975 // Parse num_element_value_pairs and element_value_pairs and visit these values.
976 currentAnnotationOffset =
977 readElementValues(
978 recordComponentVisitor.visitAnnotation(annotationDescriptor, /* visible = */ true),
979 currentAnnotationOffset,
980 /* named = */ true,
981 charBuffer);
982 }
983 }
984
985 // Visit the RuntimeInvisibleAnnotations attribute.
986 if (runtimeInvisibleAnnotationsOffset != 0) {
987 int numAnnotations = readUnsignedShort(runtimeInvisibleAnnotationsOffset);
988 int currentAnnotationOffset = runtimeInvisibleAnnotationsOffset + 2;
989 while (numAnnotations-- > 0) {
990 // Parse the type_index field.
991 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
992 currentAnnotationOffset += 2;
993 // Parse num_element_value_pairs and element_value_pairs and visit these values.
994 currentAnnotationOffset =
995 readElementValues(
996 recordComponentVisitor.visitAnnotation(annotationDescriptor, /* visible = */ false),
997 currentAnnotationOffset,
998 /* named = */ true,
999 charBuffer);
1000 }
1001 }
1002
1003 // Visit the RuntimeVisibleTypeAnnotations attribute.
1004 if (runtimeVisibleTypeAnnotationsOffset != 0) {
1005 int numAnnotations = readUnsignedShort(runtimeVisibleTypeAnnotationsOffset);
1006 int currentAnnotationOffset = runtimeVisibleTypeAnnotationsOffset + 2;
1007 while (numAnnotations-- > 0) {
1008 // Parse the target_type, target_info and target_path fields.
1009 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
1010 // Parse the type_index field.
1011 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1012 currentAnnotationOffset += 2;
1013 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1014 currentAnnotationOffset =
1015 readElementValues(
1016 recordComponentVisitor.visitTypeAnnotation(
1017 context.currentTypeAnnotationTarget,
1018 context.currentTypeAnnotationTargetPath,
1019 annotationDescriptor,
1020 /* visible = */ true),
1021 currentAnnotationOffset,
1022 /* named = */ true,
1023 charBuffer);
1024 }
1025 }
1026
1027 // Visit the RuntimeInvisibleTypeAnnotations attribute.
1028 if (runtimeInvisibleTypeAnnotationsOffset != 0) {
1029 int numAnnotations = readUnsignedShort(runtimeInvisibleTypeAnnotationsOffset);
1030 int currentAnnotationOffset = runtimeInvisibleTypeAnnotationsOffset + 2;
1031 while (numAnnotations-- > 0) {
1032 // Parse the target_type, target_info and target_path fields.
1033 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
1034 // Parse the type_index field.
1035 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1036 currentAnnotationOffset += 2;
1037 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1038 currentAnnotationOffset =
1039 readElementValues(
1040 recordComponentVisitor.visitTypeAnnotation(
1041 context.currentTypeAnnotationTarget,
1042 context.currentTypeAnnotationTargetPath,
1043 annotationDescriptor,
1044 /* visible = */ false),
1045 currentAnnotationOffset,
1046 /* named = */ true,
1047 charBuffer);
1048 }
1049 }
1050
1051 // Visit the non standard attributes.
1052 while (attributes != null) {
1053 // Copy and reset the nextAttribute field so that it can also be used in FieldWriter.
1054 Attribute nextAttribute = attributes.nextAttribute;
1055 attributes.nextAttribute = null;
1056 recordComponentVisitor.visitAttribute(attributes);
1057 attributes = nextAttribute;
1058 }
1059
1060 // Visit the end of the field.
1061 recordComponentVisitor.visitEnd();
1062 return currentOffset;
1063 }
1064
1065 /**
1066 * Reads a JVMS field_info structure and makes the given visitor visit it.
1067 *
1068 * @param classVisitor the visitor that must visit the field.
1069 * @param context information about the class being parsed.
1070 * @param fieldInfoOffset the start offset of the field_info structure.
1071 * @return the offset of the first byte following the field_info structure.
1072 */
1073 private int readField(
1074 final ClassVisitor classVisitor, final Context context, final int fieldInfoOffset) {
1075 char[] charBuffer = context.charBuffer;
1076
1077 // Read the access_flags, name_index and descriptor_index fields.
1078 int currentOffset = fieldInfoOffset;
1079 int accessFlags = readUnsignedShort(currentOffset);
1080 String name = readUTF8(currentOffset + 2, charBuffer);
1081 String descriptor = readUTF8(currentOffset + 4, charBuffer);
1082 currentOffset += 6;
1083
1084 // Read the field attributes (the variables are ordered as in Section 4.7 of the JVMS).
1085 // Attribute offsets exclude the attribute_name_index and attribute_length fields.
1086 // - The value corresponding to the ConstantValue attribute, or null.
1087 Object constantValue = null;
1088 // - The string corresponding to the Signature attribute, or null.
1089 String signature = null;
1090 // - The offset of the RuntimeVisibleAnnotations attribute, or 0.
1091 int runtimeVisibleAnnotationsOffset = 0;
1092 // - The offset of the RuntimeInvisibleAnnotations attribute, or 0.
1093 int runtimeInvisibleAnnotationsOffset = 0;
1094 // - The offset of the RuntimeVisibleTypeAnnotations attribute, or 0.
1095 int runtimeVisibleTypeAnnotationsOffset = 0;
1096 // - The offset of the RuntimeInvisibleTypeAnnotations attribute, or 0.
1097 int runtimeInvisibleTypeAnnotationsOffset = 0;
1098 // - The non standard attributes (linked with their {@link Attribute#nextAttribute} field).
1099 // This list in the <i>reverse order</i> or their order in the ClassFile structure.
1100 Attribute attributes = null;
1101
1102 int attributesCount = readUnsignedShort(currentOffset);
1103 currentOffset += 2;
1104 while (attributesCount-- > 0) {
1105 // Read the attribute_info's attribute_name and attribute_length fields.
1106 String attributeName = readUTF8(currentOffset, charBuffer);
1107 int attributeLength = readInt(currentOffset + 2);
1108 currentOffset += 6;
1109 // The tests are sorted in decreasing frequency order (based on frequencies observed on
1110 // typical classes).
1111 if (Constants.CONSTANT_VALUE.equals(attributeName)) {
1112 int constantvalueIndex = readUnsignedShort(currentOffset);
1113 constantValue = constantvalueIndex == 0 ? null : readConst(constantvalueIndex, charBuffer);
1114 } else if (Constants.SIGNATURE.equals(attributeName)) {
1115 signature = readUTF8(currentOffset, charBuffer);
1116 } else if (Constants.DEPRECATED.equals(attributeName)) {
1117 accessFlags |= Opcodes.ACC_DEPRECATED;
1118 } else if (Constants.SYNTHETIC.equals(attributeName)) {
1119 accessFlags |= Opcodes.ACC_SYNTHETIC;
1120 } else if (Constants.RUNTIME_VISIBLE_ANNOTATIONS.equals(attributeName)) {
1121 runtimeVisibleAnnotationsOffset = currentOffset;
1122 } else if (Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
1123 runtimeVisibleTypeAnnotationsOffset = currentOffset;
1124 } else if (Constants.RUNTIME_INVISIBLE_ANNOTATIONS.equals(attributeName)) {
1125 runtimeInvisibleAnnotationsOffset = currentOffset;
1126 } else if (Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
1127 runtimeInvisibleTypeAnnotationsOffset = currentOffset;
1128 } else {
1129 Attribute attribute =
1130 readAttribute(
1131 context.attributePrototypes,
1132 attributeName,
1133 currentOffset,
1134 attributeLength,
1135 charBuffer,
1136 -1,
1137 null);
1138 attribute.nextAttribute = attributes;
1139 attributes = attribute;
1140 }
1141 currentOffset += attributeLength;
1142 }
1143
1144 // Visit the field declaration.
1145 FieldVisitor fieldVisitor =
1146 classVisitor.visitField(accessFlags, name, descriptor, signature, constantValue);
1147 if (fieldVisitor == null) {
1148 return currentOffset;
1149 }
1150
1151 // Visit the RuntimeVisibleAnnotations attribute.
1152 if (runtimeVisibleAnnotationsOffset != 0) {
1153 int numAnnotations = readUnsignedShort(runtimeVisibleAnnotationsOffset);
1154 int currentAnnotationOffset = runtimeVisibleAnnotationsOffset + 2;
1155 while (numAnnotations-- > 0) {
1156 // Parse the type_index field.
1157 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1158 currentAnnotationOffset += 2;
1159 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1160 currentAnnotationOffset =
1161 readElementValues(
1162 fieldVisitor.visitAnnotation(annotationDescriptor, /* visible = */ true),
1163 currentAnnotationOffset,
1164 /* named = */ true,
1165 charBuffer);
1166 }
1167 }
1168
1169 // Visit the RuntimeInvisibleAnnotations attribute.
1170 if (runtimeInvisibleAnnotationsOffset != 0) {
1171 int numAnnotations = readUnsignedShort(runtimeInvisibleAnnotationsOffset);
1172 int currentAnnotationOffset = runtimeInvisibleAnnotationsOffset + 2;
1173 while (numAnnotations-- > 0) {
1174 // Parse the type_index field.
1175 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1176 currentAnnotationOffset += 2;
1177 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1178 currentAnnotationOffset =
1179 readElementValues(
1180 fieldVisitor.visitAnnotation(annotationDescriptor, /* visible = */ false),
1181 currentAnnotationOffset,
1182 /* named = */ true,
1183 charBuffer);
1184 }
1185 }
1186
1187 // Visit the RuntimeVisibleTypeAnnotations attribute.
1188 if (runtimeVisibleTypeAnnotationsOffset != 0) {
1189 int numAnnotations = readUnsignedShort(runtimeVisibleTypeAnnotationsOffset);
1190 int currentAnnotationOffset = runtimeVisibleTypeAnnotationsOffset + 2;
1191 while (numAnnotations-- > 0) {
1192 // Parse the target_type, target_info and target_path fields.
1193 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
1194 // Parse the type_index field.
1195 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1196 currentAnnotationOffset += 2;
1197 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1198 currentAnnotationOffset =
1199 readElementValues(
1200 fieldVisitor.visitTypeAnnotation(
1201 context.currentTypeAnnotationTarget,
1202 context.currentTypeAnnotationTargetPath,
1203 annotationDescriptor,
1204 /* visible = */ true),
1205 currentAnnotationOffset,
1206 /* named = */ true,
1207 charBuffer);
1208 }
1209 }
1210
1211 // Visit the RuntimeInvisibleTypeAnnotations attribute.
1212 if (runtimeInvisibleTypeAnnotationsOffset != 0) {
1213 int numAnnotations = readUnsignedShort(runtimeInvisibleTypeAnnotationsOffset);
1214 int currentAnnotationOffset = runtimeInvisibleTypeAnnotationsOffset + 2;
1215 while (numAnnotations-- > 0) {
1216 // Parse the target_type, target_info and target_path fields.
1217 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
1218 // Parse the type_index field.
1219 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1220 currentAnnotationOffset += 2;
1221 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1222 currentAnnotationOffset =
1223 readElementValues(
1224 fieldVisitor.visitTypeAnnotation(
1225 context.currentTypeAnnotationTarget,
1226 context.currentTypeAnnotationTargetPath,
1227 annotationDescriptor,
1228 /* visible = */ false),
1229 currentAnnotationOffset,
1230 /* named = */ true,
1231 charBuffer);
1232 }
1233 }
1234
1235 // Visit the non standard attributes.
1236 while (attributes != null) {
1237 // Copy and reset the nextAttribute field so that it can also be used in FieldWriter.
1238 Attribute nextAttribute = attributes.nextAttribute;
1239 attributes.nextAttribute = null;
1240 fieldVisitor.visitAttribute(attributes);
1241 attributes = nextAttribute;
1242 }
1243
1244 // Visit the end of the field.
1245 fieldVisitor.visitEnd();
1246 return currentOffset;
1247 }
1248
1249 /**
1250 * Reads a JVMS method_info structure and makes the given visitor visit it.
1251 *
1252 * @param classVisitor the visitor that must visit the method.
1253 * @param context information about the class being parsed.
1254 * @param methodInfoOffset the start offset of the method_info structure.
1255 * @return the offset of the first byte following the method_info structure.
1256 */
1257 private int readMethod(
1258 final ClassVisitor classVisitor, final Context context, final int methodInfoOffset) {
1259 char[] charBuffer = context.charBuffer;
1260
1261 // Read the access_flags, name_index and descriptor_index fields.
1262 int currentOffset = methodInfoOffset;
1263 context.currentMethodAccessFlags = readUnsignedShort(currentOffset);
1264 context.currentMethodName = readUTF8(currentOffset + 2, charBuffer);
1265 context.currentMethodDescriptor = readUTF8(currentOffset + 4, charBuffer);
1266 currentOffset += 6;
1267
1268 // Read the method attributes (the variables are ordered as in Section 4.7 of the JVMS).
1269 // Attribute offsets exclude the attribute_name_index and attribute_length fields.
1270 // - The offset of the Code attribute, or 0.
1271 int codeOffset = 0;
1272 // - The offset of the Exceptions attribute, or 0.
1273 int exceptionsOffset = 0;
1274 // - The strings corresponding to the Exceptions attribute, or null.
1275 String[] exceptions = null;
1276 // - Whether the method has a Synthetic attribute.
1277 boolean synthetic = false;
1278 // - The constant pool index contained in the Signature attribute, or 0.
1279 int signatureIndex = 0;
1280 // - The offset of the RuntimeVisibleAnnotations attribute, or 0.
1281 int runtimeVisibleAnnotationsOffset = 0;
1282 // - The offset of the RuntimeInvisibleAnnotations attribute, or 0.
1283 int runtimeInvisibleAnnotationsOffset = 0;
1284 // - The offset of the RuntimeVisibleParameterAnnotations attribute, or 0.
1285 int runtimeVisibleParameterAnnotationsOffset = 0;
1286 // - The offset of the RuntimeInvisibleParameterAnnotations attribute, or 0.
1287 int runtimeInvisibleParameterAnnotationsOffset = 0;
1288 // - The offset of the RuntimeVisibleTypeAnnotations attribute, or 0.
1289 int runtimeVisibleTypeAnnotationsOffset = 0;
1290 // - The offset of the RuntimeInvisibleTypeAnnotations attribute, or 0.
1291 int runtimeInvisibleTypeAnnotationsOffset = 0;
1292 // - The offset of the AnnotationDefault attribute, or 0.
1293 int annotationDefaultOffset = 0;
1294 // - The offset of the MethodParameters attribute, or 0.
1295 int methodParametersOffset = 0;
1296 // - The non standard attributes (linked with their {@link Attribute#nextAttribute} field).
1297 // This list in the <i>reverse order</i> or their order in the ClassFile structure.
1298 Attribute attributes = null;
1299
1300 int attributesCount = readUnsignedShort(currentOffset);
1301 currentOffset += 2;
1302 while (attributesCount-- > 0) {
1303 // Read the attribute_info's attribute_name and attribute_length fields.
1304 String attributeName = readUTF8(currentOffset, charBuffer);
1305 int attributeLength = readInt(currentOffset + 2);
1306 currentOffset += 6;
1307 // The tests are sorted in decreasing frequency order (based on frequencies observed on
1308 // typical classes).
1309 if (Constants.CODE.equals(attributeName)) {
1310 if ((context.parsingOptions & SKIP_CODE) == 0) {
1311 codeOffset = currentOffset;
1312 }
1313 } else if (Constants.EXCEPTIONS.equals(attributeName)) {
1314 exceptionsOffset = currentOffset;
1315 exceptions = new String[readUnsignedShort(exceptionsOffset)];
1316 int currentExceptionOffset = exceptionsOffset + 2;
1317 for (int i = 0; i < exceptions.length; ++i) {
1318 exceptions[i] = readClass(currentExceptionOffset, charBuffer);
1319 currentExceptionOffset += 2;
1320 }
1321 } else if (Constants.SIGNATURE.equals(attributeName)) {
1322 signatureIndex = readUnsignedShort(currentOffset);
1323 } else if (Constants.DEPRECATED.equals(attributeName)) {
1324 context.currentMethodAccessFlags |= Opcodes.ACC_DEPRECATED;
1325 } else if (Constants.RUNTIME_VISIBLE_ANNOTATIONS.equals(attributeName)) {
1326 runtimeVisibleAnnotationsOffset = currentOffset;
1327 } else if (Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
1328 runtimeVisibleTypeAnnotationsOffset = currentOffset;
1329 } else if (Constants.ANNOTATION_DEFAULT.equals(attributeName)) {
1330 annotationDefaultOffset = currentOffset;
1331 } else if (Constants.SYNTHETIC.equals(attributeName)) {
1332 synthetic = true;
1333 context.currentMethodAccessFlags |= Opcodes.ACC_SYNTHETIC;
1334 } else if (Constants.RUNTIME_INVISIBLE_ANNOTATIONS.equals(attributeName)) {
1335 runtimeInvisibleAnnotationsOffset = currentOffset;
1336 } else if (Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
1337 runtimeInvisibleTypeAnnotationsOffset = currentOffset;
1338 } else if (Constants.RUNTIME_VISIBLE_PARAMETER_ANNOTATIONS.equals(attributeName)) {
1339 runtimeVisibleParameterAnnotationsOffset = currentOffset;
1340 } else if (Constants.RUNTIME_INVISIBLE_PARAMETER_ANNOTATIONS.equals(attributeName)) {
1341 runtimeInvisibleParameterAnnotationsOffset = currentOffset;
1342 } else if (Constants.METHOD_PARAMETERS.equals(attributeName)) {
1343 methodParametersOffset = currentOffset;
1344 } else {
1345 Attribute attribute =
1346 readAttribute(
1347 context.attributePrototypes,
1348 attributeName,
1349 currentOffset,
1350 attributeLength,
1351 charBuffer,
1352 -1,
1353 null);
1354 attribute.nextAttribute = attributes;
1355 attributes = attribute;
1356 }
1357 currentOffset += attributeLength;
1358 }
1359
1360 // Visit the method declaration.
1361 MethodVisitor methodVisitor =
1362 classVisitor.visitMethod(
1363 context.currentMethodAccessFlags,
1364 context.currentMethodName,
1365 context.currentMethodDescriptor,
1366 signatureIndex == 0 ? null : readUtf(signatureIndex, charBuffer),
1367 exceptions);
1368 if (methodVisitor == null) {
1369 return currentOffset;
1370 }
1371
1372 // If the returned MethodVisitor is in fact a MethodWriter, it means there is no method
1373 // adapter between the reader and the writer. In this case, it might be possible to copy
1374 // the method attributes directly into the writer. If so, return early without visiting
1375 // the content of these attributes.
1376 if (methodVisitor instanceof MethodWriter) {
1377 MethodWriter methodWriter = (MethodWriter) methodVisitor;
1378 if (methodWriter.canCopyMethodAttributes(
1379 this,
1380 synthetic,
1381 (context.currentMethodAccessFlags & Opcodes.ACC_DEPRECATED) != 0,
1382 readUnsignedShort(methodInfoOffset + 4),
1383 signatureIndex,
1384 exceptionsOffset)) {
1385 methodWriter.setMethodAttributesSource(methodInfoOffset, currentOffset - methodInfoOffset);
1386 return currentOffset;
1387 }
1388 }
1389
1390 // Visit the MethodParameters attribute.
1391 if (methodParametersOffset != 0 && (context.parsingOptions & SKIP_DEBUG) == 0) {
1392 int parametersCount = readByte(methodParametersOffset);
1393 int currentParameterOffset = methodParametersOffset + 1;
1394 while (parametersCount-- > 0) {
1395 // Read the name_index and access_flags fields and visit them.
1396 methodVisitor.visitParameter(
1397 readUTF8(currentParameterOffset, charBuffer),
1398 readUnsignedShort(currentParameterOffset + 2));
1399 currentParameterOffset += 4;
1400 }
1401 }
1402
1403 // Visit the AnnotationDefault attribute.
1404 if (annotationDefaultOffset != 0) {
1405 AnnotationVisitor annotationVisitor = methodVisitor.visitAnnotationDefault();
1406 readElementValue(annotationVisitor, annotationDefaultOffset, null, charBuffer);
1407 if (annotationVisitor != null) {
1408 annotationVisitor.visitEnd();
1409 }
1410 }
1411
1412 // Visit the RuntimeVisibleAnnotations attribute.
1413 if (runtimeVisibleAnnotationsOffset != 0) {
1414 int numAnnotations = readUnsignedShort(runtimeVisibleAnnotationsOffset);
1415 int currentAnnotationOffset = runtimeVisibleAnnotationsOffset + 2;
1416 while (numAnnotations-- > 0) {
1417 // Parse the type_index field.
1418 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1419 currentAnnotationOffset += 2;
1420 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1421 currentAnnotationOffset =
1422 readElementValues(
1423 methodVisitor.visitAnnotation(annotationDescriptor, /* visible = */ true),
1424 currentAnnotationOffset,
1425 /* named = */ true,
1426 charBuffer);
1427 }
1428 }
1429
1430 // Visit the RuntimeInvisibleAnnotations attribute.
1431 if (runtimeInvisibleAnnotationsOffset != 0) {
1432 int numAnnotations = readUnsignedShort(runtimeInvisibleAnnotationsOffset);
1433 int currentAnnotationOffset = runtimeInvisibleAnnotationsOffset + 2;
1434 while (numAnnotations-- > 0) {
1435 // Parse the type_index field.
1436 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1437 currentAnnotationOffset += 2;
1438 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1439 currentAnnotationOffset =
1440 readElementValues(
1441 methodVisitor.visitAnnotation(annotationDescriptor, /* visible = */ false),
1442 currentAnnotationOffset,
1443 /* named = */ true,
1444 charBuffer);
1445 }
1446 }
1447
1448 // Visit the RuntimeVisibleTypeAnnotations attribute.
1449 if (runtimeVisibleTypeAnnotationsOffset != 0) {
1450 int numAnnotations = readUnsignedShort(runtimeVisibleTypeAnnotationsOffset);
1451 int currentAnnotationOffset = runtimeVisibleTypeAnnotationsOffset + 2;
1452 while (numAnnotations-- > 0) {
1453 // Parse the target_type, target_info and target_path fields.
1454 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
1455 // Parse the type_index field.
1456 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1457 currentAnnotationOffset += 2;
1458 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1459 currentAnnotationOffset =
1460 readElementValues(
1461 methodVisitor.visitTypeAnnotation(
1462 context.currentTypeAnnotationTarget,
1463 context.currentTypeAnnotationTargetPath,
1464 annotationDescriptor,
1465 /* visible = */ true),
1466 currentAnnotationOffset,
1467 /* named = */ true,
1468 charBuffer);
1469 }
1470 }
1471
1472 // Visit the RuntimeInvisibleTypeAnnotations attribute.
1473 if (runtimeInvisibleTypeAnnotationsOffset != 0) {
1474 int numAnnotations = readUnsignedShort(runtimeInvisibleTypeAnnotationsOffset);
1475 int currentAnnotationOffset = runtimeInvisibleTypeAnnotationsOffset + 2;
1476 while (numAnnotations-- > 0) {
1477 // Parse the target_type, target_info and target_path fields.
1478 currentAnnotationOffset = readTypeAnnotationTarget(context, currentAnnotationOffset);
1479 // Parse the type_index field.
1480 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
1481 currentAnnotationOffset += 2;
1482 // Parse num_element_value_pairs and element_value_pairs and visit these values.
1483 currentAnnotationOffset =
1484 readElementValues(
1485 methodVisitor.visitTypeAnnotation(
1486 context.currentTypeAnnotationTarget,
1487 context.currentTypeAnnotationTargetPath,
1488 annotationDescriptor,
1489 /* visible = */ false),
1490 currentAnnotationOffset,
1491 /* named = */ true,
1492 charBuffer);
1493 }
1494 }
1495
1496 // Visit the RuntimeVisibleParameterAnnotations attribute.
1497 if (runtimeVisibleParameterAnnotationsOffset != 0) {
1498 readParameterAnnotations(
1499 methodVisitor, context, runtimeVisibleParameterAnnotationsOffset, /* visible = */ true);
1500 }
1501
1502 // Visit the RuntimeInvisibleParameterAnnotations attribute.
1503 if (runtimeInvisibleParameterAnnotationsOffset != 0) {
1504 readParameterAnnotations(
1505 methodVisitor,
1506 context,
1507 runtimeInvisibleParameterAnnotationsOffset,
1508 /* visible = */ false);
1509 }
1510
1511 // Visit the non standard attributes.
1512 while (attributes != null) {
1513 // Copy and reset the nextAttribute field so that it can also be used in MethodWriter.
1514 Attribute nextAttribute = attributes.nextAttribute;
1515 attributes.nextAttribute = null;
1516 methodVisitor.visitAttribute(attributes);
1517 attributes = nextAttribute;
1518 }
1519
1520 // Visit the Code attribute.
1521 if (codeOffset != 0) {
1522 methodVisitor.visitCode();
1523 readCode(methodVisitor, context, codeOffset);
1524 }
1525
1526 // Visit the end of the method.
1527 methodVisitor.visitEnd();
1528 return currentOffset;
1529 }
1530
1531 // ----------------------------------------------------------------------------------------------
1532 // Methods to parse a Code attribute
1533 // ----------------------------------------------------------------------------------------------
1534
1535 /**
1536 * Reads a JVMS 'Code' attribute and makes the given visitor visit it.
1537 *
1538 * @param methodVisitor the visitor that must visit the Code attribute.
1539 * @param context information about the class being parsed.
1540 * @param codeOffset the start offset in {@link #classFileBuffer} of the Code attribute, excluding
1541 * its attribute_name_index and attribute_length fields.
1542 */
1543 private void readCode(
1544 final MethodVisitor methodVisitor, final Context context, final int codeOffset) {
1545 int currentOffset = codeOffset;
1546
1547 // Read the max_stack, max_locals and code_length fields.
1548 final byte[] classBuffer = classFileBuffer;
1549 final char[] charBuffer = context.charBuffer;
1550 final int maxStack = readUnsignedShort(currentOffset);
1551 final int maxLocals = readUnsignedShort(currentOffset + 2);
1552 final int codeLength = readInt(currentOffset + 4);
1553 currentOffset += 8;
1554 if (codeLength > classFileBuffer.length - currentOffset) {
1555 throw new IllegalArgumentException();
1556 }
1557
1558 // Read the bytecode 'code' array to create a label for each referenced instruction.
1559 final int bytecodeStartOffset = currentOffset;
1560 final int bytecodeEndOffset = currentOffset + codeLength;
1561 final Label[] labels = context.currentMethodLabels = new Label[codeLength + 1];
1562 while (currentOffset < bytecodeEndOffset) {
1563 final int bytecodeOffset = currentOffset - bytecodeStartOffset;
1564 final int opcode = classBuffer[currentOffset] & 0xFF;
1565 switch (opcode) {
1566 case Opcodes.NOP:
1567 case Opcodes.ACONST_NULL:
1568 case Opcodes.ICONST_M1:
1569 case Opcodes.ICONST_0:
1570 case Opcodes.ICONST_1:
1571 case Opcodes.ICONST_2:
1572 case Opcodes.ICONST_3:
1573 case Opcodes.ICONST_4:
1574 case Opcodes.ICONST_5:
1575 case Opcodes.LCONST_0:
1576 case Opcodes.LCONST_1:
1577 case Opcodes.FCONST_0:
1578 case Opcodes.FCONST_1:
1579 case Opcodes.FCONST_2:
1580 case Opcodes.DCONST_0:
1581 case Opcodes.DCONST_1:
1582 case Opcodes.IALOAD:
1583 case Opcodes.LALOAD:
1584 case Opcodes.FALOAD:
1585 case Opcodes.DALOAD:
1586 case Opcodes.AALOAD:
1587 case Opcodes.BALOAD:
1588 case Opcodes.CALOAD:
1589 case Opcodes.SALOAD:
1590 case Opcodes.IASTORE:
1591 case Opcodes.LASTORE:
1592 case Opcodes.FASTORE:
1593 case Opcodes.DASTORE:
1594 case Opcodes.AASTORE:
1595 case Opcodes.BASTORE:
1596 case Opcodes.CASTORE:
1597 case Opcodes.SASTORE:
1598 case Opcodes.POP:
1599 case Opcodes.POP2:
1600 case Opcodes.DUP:
1601 case Opcodes.DUP_X1:
1602 case Opcodes.DUP_X2:
1603 case Opcodes.DUP2:
1604 case Opcodes.DUP2_X1:
1605 case Opcodes.DUP2_X2:
1606 case Opcodes.SWAP:
1607 case Opcodes.IADD:
1608 case Opcodes.LADD:
1609 case Opcodes.FADD:
1610 case Opcodes.DADD:
1611 case Opcodes.ISUB:
1612 case Opcodes.LSUB:
1613 case Opcodes.FSUB:
1614 case Opcodes.DSUB:
1615 case Opcodes.IMUL:
1616 case Opcodes.LMUL:
1617 case Opcodes.FMUL:
1618 case Opcodes.DMUL:
1619 case Opcodes.IDIV:
1620 case Opcodes.LDIV:
1621 case Opcodes.FDIV:
1622 case Opcodes.DDIV:
1623 case Opcodes.IREM:
1624 case Opcodes.LREM:
1625 case Opcodes.FREM:
1626 case Opcodes.DREM:
1627 case Opcodes.INEG:
1628 case Opcodes.LNEG:
1629 case Opcodes.FNEG:
1630 case Opcodes.DNEG:
1631 case Opcodes.ISHL:
1632 case Opcodes.LSHL:
1633 case Opcodes.ISHR:
1634 case Opcodes.LSHR:
1635 case Opcodes.IUSHR:
1636 case Opcodes.LUSHR:
1637 case Opcodes.IAND:
1638 case Opcodes.LAND:
1639 case Opcodes.IOR:
1640 case Opcodes.LOR:
1641 case Opcodes.IXOR:
1642 case Opcodes.LXOR:
1643 case Opcodes.I2L:
1644 case Opcodes.I2F:
1645 case Opcodes.I2D:
1646 case Opcodes.L2I:
1647 case Opcodes.L2F:
1648 case Opcodes.L2D:
1649 case Opcodes.F2I:
1650 case Opcodes.F2L:
1651 case Opcodes.F2D:
1652 case Opcodes.D2I:
1653 case Opcodes.D2L:
1654 case Opcodes.D2F:
1655 case Opcodes.I2B:
1656 case Opcodes.I2C:
1657 case Opcodes.I2S:
1658 case Opcodes.LCMP:
1659 case Opcodes.FCMPL:
1660 case Opcodes.FCMPG:
1661 case Opcodes.DCMPL:
1662 case Opcodes.DCMPG:
1663 case Opcodes.IRETURN:
1664 case Opcodes.LRETURN:
1665 case Opcodes.FRETURN:
1666 case Opcodes.DRETURN:
1667 case Opcodes.ARETURN:
1668 case Opcodes.RETURN:
1669 case Opcodes.ARRAYLENGTH:
1670 case Opcodes.ATHROW:
1671 case Opcodes.MONITORENTER:
1672 case Opcodes.MONITOREXIT:
1673 case Constants.ILOAD_0:
1674 case Constants.ILOAD_1:
1675 case Constants.ILOAD_2:
1676 case Constants.ILOAD_3:
1677 case Constants.LLOAD_0:
1678 case Constants.LLOAD_1:
1679 case Constants.LLOAD_2:
1680 case Constants.LLOAD_3:
1681 case Constants.FLOAD_0:
1682 case Constants.FLOAD_1:
1683 case Constants.FLOAD_2:
1684 case Constants.FLOAD_3:
1685 case Constants.DLOAD_0:
1686 case Constants.DLOAD_1:
1687 case Constants.DLOAD_2:
1688 case Constants.DLOAD_3:
1689 case Constants.ALOAD_0:
1690 case Constants.ALOAD_1:
1691 case Constants.ALOAD_2:
1692 case Constants.ALOAD_3:
1693 case Constants.ISTORE_0:
1694 case Constants.ISTORE_1:
1695 case Constants.ISTORE_2:
1696 case Constants.ISTORE_3:
1697 case Constants.LSTORE_0:
1698 case Constants.LSTORE_1:
1699 case Constants.LSTORE_2:
1700 case Constants.LSTORE_3:
1701 case Constants.FSTORE_0:
1702 case Constants.FSTORE_1:
1703 case Constants.FSTORE_2:
1704 case Constants.FSTORE_3:
1705 case Constants.DSTORE_0:
1706 case Constants.DSTORE_1:
1707 case Constants.DSTORE_2:
1708 case Constants.DSTORE_3:
1709 case Constants.ASTORE_0:
1710 case Constants.ASTORE_1:
1711 case Constants.ASTORE_2:
1712 case Constants.ASTORE_3:
1713 currentOffset += 1;
1714 break;
1715 case Opcodes.IFEQ:
1716 case Opcodes.IFNE:
1717 case Opcodes.IFLT:
1718 case Opcodes.IFGE:
1719 case Opcodes.IFGT:
1720 case Opcodes.IFLE:
1721 case Opcodes.IF_ICMPEQ:
1722 case Opcodes.IF_ICMPNE:
1723 case Opcodes.IF_ICMPLT:
1724 case Opcodes.IF_ICMPGE:
1725 case Opcodes.IF_ICMPGT:
1726 case Opcodes.IF_ICMPLE:
1727 case Opcodes.IF_ACMPEQ:
1728 case Opcodes.IF_ACMPNE:
1729 case Opcodes.GOTO:
1730 case Opcodes.JSR:
1731 case Opcodes.IFNULL:
1732 case Opcodes.IFNONNULL:
1733 createLabel(bytecodeOffset + readShort(currentOffset + 1), labels);
1734 currentOffset += 3;
1735 break;
1736 case Constants.ASM_IFEQ:
1737 case Constants.ASM_IFNE:
1738 case Constants.ASM_IFLT:
1739 case Constants.ASM_IFGE:
1740 case Constants.ASM_IFGT:
1741 case Constants.ASM_IFLE:
1742 case Constants.ASM_IF_ICMPEQ:
1743 case Constants.ASM_IF_ICMPNE:
1744 case Constants.ASM_IF_ICMPLT:
1745 case Constants.ASM_IF_ICMPGE:
1746 case Constants.ASM_IF_ICMPGT:
1747 case Constants.ASM_IF_ICMPLE:
1748 case Constants.ASM_IF_ACMPEQ:
1749 case Constants.ASM_IF_ACMPNE:
1750 case Constants.ASM_GOTO:
1751 case Constants.ASM_JSR:
1752 case Constants.ASM_IFNULL:
1753 case Constants.ASM_IFNONNULL:
1754 createLabel(bytecodeOffset + readUnsignedShort(currentOffset + 1), labels);
1755 currentOffset += 3;
1756 break;
1757 case Constants.GOTO_W:
1758 case Constants.JSR_W:
1759 case Constants.ASM_GOTO_W:
1760 createLabel(bytecodeOffset + readInt(currentOffset + 1), labels);
1761 currentOffset += 5;
1762 break;
1763 case Constants.WIDE:
1764 switch (classBuffer[currentOffset + 1] & 0xFF) {
1765 case Opcodes.ILOAD:
1766 case Opcodes.FLOAD:
1767 case Opcodes.ALOAD:
1768 case Opcodes.LLOAD:
1769 case Opcodes.DLOAD:
1770 case Opcodes.ISTORE:
1771 case Opcodes.FSTORE:
1772 case Opcodes.ASTORE:
1773 case Opcodes.LSTORE:
1774 case Opcodes.DSTORE:
1775 case Opcodes.RET:
1776 currentOffset += 4;
1777 break;
1778 case Opcodes.IINC:
1779 currentOffset += 6;
1780 break;
1781 default:
1782 throw new IllegalArgumentException();
1783 }
1784 break;
1785 case Opcodes.TABLESWITCH:
1786 // Skip 0 to 3 padding bytes.
1787 currentOffset += 4 - (bytecodeOffset & 3);
1788 // Read the default label and the number of table entries.
1789 createLabel(bytecodeOffset + readInt(currentOffset), labels);
1790 int numTableEntries = readInt(currentOffset + 8) - readInt(currentOffset + 4) + 1;
1791 currentOffset += 12;
1792 // Read the table labels.
1793 while (numTableEntries-- > 0) {
1794 createLabel(bytecodeOffset + readInt(currentOffset), labels);
1795 currentOffset += 4;
1796 }
1797 break;
1798 case Opcodes.LOOKUPSWITCH:
1799 // Skip 0 to 3 padding bytes.
1800 currentOffset += 4 - (bytecodeOffset & 3);
1801 // Read the default label and the number of switch cases.
1802 createLabel(bytecodeOffset + readInt(currentOffset), labels);
1803 int numSwitchCases = readInt(currentOffset + 4);
1804 currentOffset += 8;
1805 // Read the switch labels.
1806 while (numSwitchCases-- > 0) {
1807 createLabel(bytecodeOffset + readInt(currentOffset + 4), labels);
1808 currentOffset += 8;
1809 }
1810 break;
1811 case Opcodes.ILOAD:
1812 case Opcodes.LLOAD:
1813 case Opcodes.FLOAD:
1814 case Opcodes.DLOAD:
1815 case Opcodes.ALOAD:
1816 case Opcodes.ISTORE:
1817 case Opcodes.LSTORE:
1818 case Opcodes.FSTORE:
1819 case Opcodes.DSTORE:
1820 case Opcodes.ASTORE:
1821 case Opcodes.RET:
1822 case Opcodes.BIPUSH:
1823 case Opcodes.NEWARRAY:
1824 case Opcodes.LDC:
1825 currentOffset += 2;
1826 break;
1827 case Opcodes.SIPUSH:
1828 case Constants.LDC_W:
1829 case Constants.LDC2_W:
1830 case Opcodes.GETSTATIC:
1831 case Opcodes.PUTSTATIC:
1832 case Opcodes.GETFIELD:
1833 case Opcodes.PUTFIELD:
1834 case Opcodes.INVOKEVIRTUAL:
1835 case Opcodes.INVOKESPECIAL:
1836 case Opcodes.INVOKESTATIC:
1837 case Opcodes.NEW:
1838 case Opcodes.ANEWARRAY:
1839 case Opcodes.CHECKCAST:
1840 case Opcodes.INSTANCEOF:
1841 case Opcodes.IINC:
1842 currentOffset += 3;
1843 break;
1844 case Opcodes.INVOKEINTERFACE:
1845 case Opcodes.INVOKEDYNAMIC:
1846 currentOffset += 5;
1847 break;
1848 case Opcodes.MULTIANEWARRAY:
1849 currentOffset += 4;
1850 break;
1851 default:
1852 throw new IllegalArgumentException();
1853 }
1854 }
1855
1856 // Read the 'exception_table_length' and 'exception_table' field to create a label for each
1857 // referenced instruction, and to make methodVisitor visit the corresponding try catch blocks.
1858 int exceptionTableLength = readUnsignedShort(currentOffset);
1859 currentOffset += 2;
1860 while (exceptionTableLength-- > 0) {
1861 Label start = createLabel(readUnsignedShort(currentOffset), labels);
1862 Label end = createLabel(readUnsignedShort(currentOffset + 2), labels);
1863 Label handler = createLabel(readUnsignedShort(currentOffset + 4), labels);
1864 String catchType = readUTF8(cpInfoOffsets[readUnsignedShort(currentOffset + 6)], charBuffer);
1865 currentOffset += 8;
1866 methodVisitor.visitTryCatchBlock(start, end, handler, catchType);
1867 }
1868
1869 // Read the Code attributes to create a label for each referenced instruction (the variables
1870 // are ordered as in Section 4.7 of the JVMS). Attribute offsets exclude the
1871 // attribute_name_index and attribute_length fields.
1872 // - The offset of the current 'stack_map_frame' in the StackMap[Table] attribute, or 0.
1873 // Initially, this is the offset of the first 'stack_map_frame' entry. Then this offset is
1874 // updated after each stack_map_frame is read.
1875 int stackMapFrameOffset = 0;
1876 // - The end offset of the StackMap[Table] attribute, or 0.
1877 int stackMapTableEndOffset = 0;
1878 // - Whether the stack map frames are compressed (i.e. in a StackMapTable) or not.
1879 boolean compressedFrames = true;
1880 // - The offset of the LocalVariableTable attribute, or 0.
1881 int localVariableTableOffset = 0;
1882 // - The offset of the LocalVariableTypeTable attribute, or 0.
1883 int localVariableTypeTableOffset = 0;
1884 // - The offset of each 'type_annotation' entry in the RuntimeVisibleTypeAnnotations
1885 // attribute, or null.
1886 int[] visibleTypeAnnotationOffsets = null;
1887 // - The offset of each 'type_annotation' entry in the RuntimeInvisibleTypeAnnotations
1888 // attribute, or null.
1889 int[] invisibleTypeAnnotationOffsets = null;
1890 // - The non standard attributes (linked with their {@link Attribute#nextAttribute} field).
1891 // This list in the <i>reverse order</i> or their order in the ClassFile structure.
1892 Attribute attributes = null;
1893
1894 int attributesCount = readUnsignedShort(currentOffset);
1895 currentOffset += 2;
1896 while (attributesCount-- > 0) {
1897 // Read the attribute_info's attribute_name and attribute_length fields.
1898 String attributeName = readUTF8(currentOffset, charBuffer);
1899 int attributeLength = readInt(currentOffset + 2);
1900 currentOffset += 6;
1901 if (Constants.LOCAL_VARIABLE_TABLE.equals(attributeName)) {
1902 if ((context.parsingOptions & SKIP_DEBUG) == 0) {
1903 localVariableTableOffset = currentOffset;
1904 // Parse the attribute to find the corresponding (debug only) labels.
1905 int currentLocalVariableTableOffset = currentOffset;
1906 int localVariableTableLength = readUnsignedShort(currentLocalVariableTableOffset);
1907 currentLocalVariableTableOffset += 2;
1908 while (localVariableTableLength-- > 0) {
1909 int startPc = readUnsignedShort(currentLocalVariableTableOffset);
1910 createDebugLabel(startPc, labels);
1911 int length = readUnsignedShort(currentLocalVariableTableOffset + 2);
1912 createDebugLabel(startPc + length, labels);
1913 // Skip the name_index, descriptor_index and index fields (2 bytes each).
1914 currentLocalVariableTableOffset += 10;
1915 }
1916 }
1917 } else if (Constants.LOCAL_VARIABLE_TYPE_TABLE.equals(attributeName)) {
1918 localVariableTypeTableOffset = currentOffset;
1919 // Here we do not extract the labels corresponding to the attribute content. We assume they
1920 // are the same or a subset of those of the LocalVariableTable attribute.
1921 } else if (Constants.LINE_NUMBER_TABLE.equals(attributeName)) {
1922 if ((context.parsingOptions & SKIP_DEBUG) == 0) {
1923 // Parse the attribute to find the corresponding (debug only) labels.
1924 int currentLineNumberTableOffset = currentOffset;
1925 int lineNumberTableLength = readUnsignedShort(currentLineNumberTableOffset);
1926 currentLineNumberTableOffset += 2;
1927 while (lineNumberTableLength-- > 0) {
1928 int startPc = readUnsignedShort(currentLineNumberTableOffset);
1929 int lineNumber = readUnsignedShort(currentLineNumberTableOffset + 2);
1930 currentLineNumberTableOffset += 4;
1931 createDebugLabel(startPc, labels);
1932 labels[startPc].addLineNumber(lineNumber);
1933 }
1934 }
1935 } else if (Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
1936 visibleTypeAnnotationOffsets =
1937 readTypeAnnotations(methodVisitor, context, currentOffset, /* visible = */ true);
1938 // Here we do not extract the labels corresponding to the attribute content. This would
1939 // require a full parsing of the attribute, which would need to be repeated when parsing
1940 // the bytecode instructions (see below). Instead, the content of the attribute is read one
1941 // type annotation at a time (i.e. after a type annotation has been visited, the next type
1942 // annotation is read), and the labels it contains are also extracted one annotation at a
1943 // time. This assumes that type annotations are ordered by increasing bytecode offset.
1944 } else if (Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS.equals(attributeName)) {
1945 invisibleTypeAnnotationOffsets =
1946 readTypeAnnotations(methodVisitor, context, currentOffset, /* visible = */ false);
1947 // Same comment as above for the RuntimeVisibleTypeAnnotations attribute.
1948 } else if (Constants.STACK_MAP_TABLE.equals(attributeName)) {
1949 if ((context.parsingOptions & SKIP_FRAMES) == 0) {
1950 stackMapFrameOffset = currentOffset + 2;
1951 stackMapTableEndOffset = currentOffset + attributeLength;
1952 }
1953 // Here we do not extract the labels corresponding to the attribute content. This would
1954 // require a full parsing of the attribute, which would need to be repeated when parsing
1955 // the bytecode instructions (see below). Instead, the content of the attribute is read one
1956 // frame at a time (i.e. after a frame has been visited, the next frame is read), and the
1957 // labels it contains are also extracted one frame at a time. Thanks to the ordering of
1958 // frames, having only a "one frame lookahead" is not a problem, i.e. it is not possible to
1959 // see an offset smaller than the offset of the current instruction and for which no Label
1960 // exist. Except for UNINITIALIZED type offsets. We solve this by parsing the stack map
1961 // table without a full decoding (see below).
1962 } else if ("StackMap".equals(attributeName)) {
1963 if ((context.parsingOptions & SKIP_FRAMES) == 0) {
1964 stackMapFrameOffset = currentOffset + 2;
1965 stackMapTableEndOffset = currentOffset + attributeLength;
1966 compressedFrames = false;
1967 }
1968 // IMPORTANT! Here we assume that the frames are ordered, as in the StackMapTable attribute,
1969 // although this is not guaranteed by the attribute format. This allows an incremental
1970 // extraction of the labels corresponding to this attribute (see the comment above for the
1971 // StackMapTable attribute).
1972 } else {
1973 Attribute attribute =
1974 readAttribute(
1975 context.attributePrototypes,
1976 attributeName,
1977 currentOffset,
1978 attributeLength,
1979 charBuffer,
1980 codeOffset,
1981 labels);
1982 attribute.nextAttribute = attributes;
1983 attributes = attribute;
1984 }
1985 currentOffset += attributeLength;
1986 }
1987
1988 // Initialize the context fields related to stack map frames, and generate the first
1989 // (implicit) stack map frame, if needed.
1990 final boolean expandFrames = (context.parsingOptions & EXPAND_FRAMES) != 0;
1991 if (stackMapFrameOffset != 0) {
1992 // The bytecode offset of the first explicit frame is not offset_delta + 1 but only
1993 // offset_delta. Setting the implicit frame offset to -1 allows us to use of the
1994 // "offset_delta + 1" rule in all cases.
1995 context.currentFrameOffset = -1;
1996 context.currentFrameType = 0;
1997 context.currentFrameLocalCount = 0;
1998 context.currentFrameLocalCountDelta = 0;
1999 context.currentFrameLocalTypes = new Object[maxLocals];
2000 context.currentFrameStackCount = 0;
2001 context.currentFrameStackTypes = new Object[maxStack];
2002 if (expandFrames) {
2003 computeImplicitFrame(context);
2004 }
2005 // Find the labels for UNINITIALIZED frame types. Instead of decoding each element of the
2006 // stack map table, we look for 3 consecutive bytes that "look like" an UNINITIALIZED type
2007 // (tag ITEM_Uninitialized, offset within bytecode bounds, NEW instruction at this offset).
2008 // We may find false positives (i.e. not real UNINITIALIZED types), but this should be rare,
2009 // and the only consequence will be the creation of an unneeded label. This is better than
2010 // creating a label for each NEW instruction, and faster than fully decoding the whole stack
2011 // map table.
2012 for (int offset = stackMapFrameOffset; offset < stackMapTableEndOffset - 2; ++offset) {
2013 if (classBuffer[offset] == Frame.ITEM_UNINITIALIZED) {
2014 int potentialBytecodeOffset = readUnsignedShort(offset + 1);
2015 if (potentialBytecodeOffset >= 0
2016 && potentialBytecodeOffset < codeLength
2017 && (classBuffer[bytecodeStartOffset + potentialBytecodeOffset] & 0xFF)
2018 == Opcodes.NEW) {
2019 createLabel(potentialBytecodeOffset, labels);
2020 }
2021 }
2022 }
2023 }
2024 if (expandFrames && (context.parsingOptions & EXPAND_ASM_INSNS) != 0) {
2025 // Expanding the ASM specific instructions can introduce F_INSERT frames, even if the method
2026 // does not currently have any frame. These inserted frames must be computed by simulating the
2027 // effect of the bytecode instructions, one by one, starting from the implicit first frame.
2028 // For this, MethodWriter needs to know maxLocals before the first instruction is visited. To
2029 // ensure this, we visit the implicit first frame here (passing only maxLocals - the rest is
2030 // computed in MethodWriter).
2031 methodVisitor.visitFrame(Opcodes.F_NEW, maxLocals, null, 0, null);
2032 }
2033
2034 // Visit the bytecode instructions. First, introduce state variables for the incremental parsing
2035 // of the type annotations.
2036
2037 // Index of the next runtime visible type annotation to read (in the
2038 // visibleTypeAnnotationOffsets array).
2039 int currentVisibleTypeAnnotationIndex = 0;
2040 // The bytecode offset of the next runtime visible type annotation to read, or -1.
2041 int currentVisibleTypeAnnotationBytecodeOffset =
2042 getTypeAnnotationBytecodeOffset(visibleTypeAnnotationOffsets, 0);
2043 // Index of the next runtime invisible type annotation to read (in the
2044 // invisibleTypeAnnotationOffsets array).
2045 int currentInvisibleTypeAnnotationIndex = 0;
2046 // The bytecode offset of the next runtime invisible type annotation to read, or -1.
2047 int currentInvisibleTypeAnnotationBytecodeOffset =
2048 getTypeAnnotationBytecodeOffset(invisibleTypeAnnotationOffsets, 0);
2049
2050 // Whether a F_INSERT stack map frame must be inserted before the current instruction.
2051 boolean insertFrame = false;
2052
2053 // The delta to subtract from a goto_w or jsr_w opcode to get the corresponding goto or jsr
2054 // opcode, or 0 if goto_w and jsr_w must be left unchanged (i.e. when expanding ASM specific
2055 // instructions).
2056 final int wideJumpOpcodeDelta =
2057 (context.parsingOptions & EXPAND_ASM_INSNS) == 0 ? Constants.WIDE_JUMP_OPCODE_DELTA : 0;
2058
2059 currentOffset = bytecodeStartOffset;
2060 while (currentOffset < bytecodeEndOffset) {
2061 final int currentBytecodeOffset = currentOffset - bytecodeStartOffset;
2062
2063 // Visit the label and the line number(s) for this bytecode offset, if any.
2064 Label currentLabel = labels[currentBytecodeOffset];
2065 if (currentLabel != null) {
2066 currentLabel.accept(methodVisitor, (context.parsingOptions & SKIP_DEBUG) == 0);
2067 }
2068
2069 // Visit the stack map frame for this bytecode offset, if any.
2070 while (stackMapFrameOffset != 0
2071 && (context.currentFrameOffset == currentBytecodeOffset
2072 || context.currentFrameOffset == -1)) {
2073 // If there is a stack map frame for this offset, make methodVisitor visit it, and read the
2074 // next stack map frame if there is one.
2075 if (context.currentFrameOffset != -1) {
2076 if (!compressedFrames || expandFrames) {
2077 methodVisitor.visitFrame(
2078 Opcodes.F_NEW,
2079 context.currentFrameLocalCount,
2080 context.currentFrameLocalTypes,
2081 context.currentFrameStackCount,
2082 context.currentFrameStackTypes);
2083 } else {
2084 methodVisitor.visitFrame(
2085 context.currentFrameType,
2086 context.currentFrameLocalCountDelta,
2087 context.currentFrameLocalTypes,
2088 context.currentFrameStackCount,
2089 context.currentFrameStackTypes);
2090 }
2091 // Since there is already a stack map frame for this bytecode offset, there is no need to
2092 // insert a new one.
2093 insertFrame = false;
2094 }
2095 if (stackMapFrameOffset < stackMapTableEndOffset) {
2096 stackMapFrameOffset =
2097 readStackMapFrame(stackMapFrameOffset, compressedFrames, expandFrames, context);
2098 } else {
2099 stackMapFrameOffset = 0;
2100 }
2101 }
2102
2103 // Insert a stack map frame for this bytecode offset, if requested by setting insertFrame to
2104 // true during the previous iteration. The actual frame content is computed in MethodWriter.
2105 if (insertFrame) {
2106 if ((context.parsingOptions & EXPAND_FRAMES) != 0) {
2107 methodVisitor.visitFrame(Constants.F_INSERT, 0, null, 0, null);
2108 }
2109 insertFrame = false;
2110 }
2111
2112 // Visit the instruction at this bytecode offset.
2113 int opcode = classBuffer[currentOffset] & 0xFF;
2114 switch (opcode) {
2115 case Opcodes.NOP:
2116 case Opcodes.ACONST_NULL:
2117 case Opcodes.ICONST_M1:
2118 case Opcodes.ICONST_0:
2119 case Opcodes.ICONST_1:
2120 case Opcodes.ICONST_2:
2121 case Opcodes.ICONST_3:
2122 case Opcodes.ICONST_4:
2123 case Opcodes.ICONST_5:
2124 case Opcodes.LCONST_0:
2125 case Opcodes.LCONST_1:
2126 case Opcodes.FCONST_0:
2127 case Opcodes.FCONST_1:
2128 case Opcodes.FCONST_2:
2129 case Opcodes.DCONST_0:
2130 case Opcodes.DCONST_1:
2131 case Opcodes.IALOAD:
2132 case Opcodes.LALOAD:
2133 case Opcodes.FALOAD:
2134 case Opcodes.DALOAD:
2135 case Opcodes.AALOAD:
2136 case Opcodes.BALOAD:
2137 case Opcodes.CALOAD:
2138 case Opcodes.SALOAD:
2139 case Opcodes.IASTORE:
2140 case Opcodes.LASTORE:
2141 case Opcodes.FASTORE:
2142 case Opcodes.DASTORE:
2143 case Opcodes.AASTORE:
2144 case Opcodes.BASTORE:
2145 case Opcodes.CASTORE:
2146 case Opcodes.SASTORE:
2147 case Opcodes.POP:
2148 case Opcodes.POP2:
2149 case Opcodes.DUP:
2150 case Opcodes.DUP_X1:
2151 case Opcodes.DUP_X2:
2152 case Opcodes.DUP2:
2153 case Opcodes.DUP2_X1:
2154 case Opcodes.DUP2_X2:
2155 case Opcodes.SWAP:
2156 case Opcodes.IADD:
2157 case Opcodes.LADD:
2158 case Opcodes.FADD:
2159 case Opcodes.DADD:
2160 case Opcodes.ISUB:
2161 case Opcodes.LSUB:
2162 case Opcodes.FSUB:
2163 case Opcodes.DSUB:
2164 case Opcodes.IMUL:
2165 case Opcodes.LMUL:
2166 case Opcodes.FMUL:
2167 case Opcodes.DMUL:
2168 case Opcodes.IDIV:
2169 case Opcodes.LDIV:
2170 case Opcodes.FDIV:
2171 case Opcodes.DDIV:
2172 case Opcodes.IREM:
2173 case Opcodes.LREM:
2174 case Opcodes.FREM:
2175 case Opcodes.DREM:
2176 case Opcodes.INEG:
2177 case Opcodes.LNEG:
2178 case Opcodes.FNEG:
2179 case Opcodes.DNEG:
2180 case Opcodes.ISHL:
2181 case Opcodes.LSHL:
2182 case Opcodes.ISHR:
2183 case Opcodes.LSHR:
2184 case Opcodes.IUSHR:
2185 case Opcodes.LUSHR:
2186 case Opcodes.IAND:
2187 case Opcodes.LAND:
2188 case Opcodes.IOR:
2189 case Opcodes.LOR:
2190 case Opcodes.IXOR:
2191 case Opcodes.LXOR:
2192 case Opcodes.I2L:
2193 case Opcodes.I2F:
2194 case Opcodes.I2D:
2195 case Opcodes.L2I:
2196 case Opcodes.L2F:
2197 case Opcodes.L2D:
2198 case Opcodes.F2I:
2199 case Opcodes.F2L:
2200 case Opcodes.F2D:
2201 case Opcodes.D2I:
2202 case Opcodes.D2L:
2203 case Opcodes.D2F:
2204 case Opcodes.I2B:
2205 case Opcodes.I2C:
2206 case Opcodes.I2S:
2207 case Opcodes.LCMP:
2208 case Opcodes.FCMPL:
2209 case Opcodes.FCMPG:
2210 case Opcodes.DCMPL:
2211 case Opcodes.DCMPG:
2212 case Opcodes.IRETURN:
2213 case Opcodes.LRETURN:
2214 case Opcodes.FRETURN:
2215 case Opcodes.DRETURN:
2216 case Opcodes.ARETURN:
2217 case Opcodes.RETURN:
2218 case Opcodes.ARRAYLENGTH:
2219 case Opcodes.ATHROW:
2220 case Opcodes.MONITORENTER:
2221 case Opcodes.MONITOREXIT:
2222 methodVisitor.visitInsn(opcode);
2223 currentOffset += 1;
2224 break;
2225 case Constants.ILOAD_0:
2226 case Constants.ILOAD_1:
2227 case Constants.ILOAD_2:
2228 case Constants.ILOAD_3:
2229 case Constants.LLOAD_0:
2230 case Constants.LLOAD_1:
2231 case Constants.LLOAD_2:
2232 case Constants.LLOAD_3:
2233 case Constants.FLOAD_0:
2234 case Constants.FLOAD_1:
2235 case Constants.FLOAD_2:
2236 case Constants.FLOAD_3:
2237 case Constants.DLOAD_0:
2238 case Constants.DLOAD_1:
2239 case Constants.DLOAD_2:
2240 case Constants.DLOAD_3:
2241 case Constants.ALOAD_0:
2242 case Constants.ALOAD_1:
2243 case Constants.ALOAD_2:
2244 case Constants.ALOAD_3:
2245 opcode -= Constants.ILOAD_0;
2246 methodVisitor.visitVarInsn(Opcodes.ILOAD + (opcode >> 2), opcode & 0x3);
2247 currentOffset += 1;
2248 break;
2249 case Constants.ISTORE_0:
2250 case Constants.ISTORE_1:
2251 case Constants.ISTORE_2:
2252 case Constants.ISTORE_3:
2253 case Constants.LSTORE_0:
2254 case Constants.LSTORE_1:
2255 case Constants.LSTORE_2:
2256 case Constants.LSTORE_3:
2257 case Constants.FSTORE_0:
2258 case Constants.FSTORE_1:
2259 case Constants.FSTORE_2:
2260 case Constants.FSTORE_3:
2261 case Constants.DSTORE_0:
2262 case Constants.DSTORE_1:
2263 case Constants.DSTORE_2:
2264 case Constants.DSTORE_3:
2265 case Constants.ASTORE_0:
2266 case Constants.ASTORE_1:
2267 case Constants.ASTORE_2:
2268 case Constants.ASTORE_3:
2269 opcode -= Constants.ISTORE_0;
2270 methodVisitor.visitVarInsn(Opcodes.ISTORE + (opcode >> 2), opcode & 0x3);
2271 currentOffset += 1;
2272 break;
2273 case Opcodes.IFEQ:
2274 case Opcodes.IFNE:
2275 case Opcodes.IFLT:
2276 case Opcodes.IFGE:
2277 case Opcodes.IFGT:
2278 case Opcodes.IFLE:
2279 case Opcodes.IF_ICMPEQ:
2280 case Opcodes.IF_ICMPNE:
2281 case Opcodes.IF_ICMPLT:
2282 case Opcodes.IF_ICMPGE:
2283 case Opcodes.IF_ICMPGT:
2284 case Opcodes.IF_ICMPLE:
2285 case Opcodes.IF_ACMPEQ:
2286 case Opcodes.IF_ACMPNE:
2287 case Opcodes.GOTO:
2288 case Opcodes.JSR:
2289 case Opcodes.IFNULL:
2290 case Opcodes.IFNONNULL:
2291 methodVisitor.visitJumpInsn(
2292 opcode, labels[currentBytecodeOffset + readShort(currentOffset + 1)]);
2293 currentOffset += 3;
2294 break;
2295 case Constants.GOTO_W:
2296 case Constants.JSR_W:
2297 methodVisitor.visitJumpInsn(
2298 opcode - wideJumpOpcodeDelta,
2299 labels[currentBytecodeOffset + readInt(currentOffset + 1)]);
2300 currentOffset += 5;
2301 break;
2302 case Constants.ASM_IFEQ:
2303 case Constants.ASM_IFNE:
2304 case Constants.ASM_IFLT:
2305 case Constants.ASM_IFGE:
2306 case Constants.ASM_IFGT:
2307 case Constants.ASM_IFLE:
2308 case Constants.ASM_IF_ICMPEQ:
2309 case Constants.ASM_IF_ICMPNE:
2310 case Constants.ASM_IF_ICMPLT:
2311 case Constants.ASM_IF_ICMPGE:
2312 case Constants.ASM_IF_ICMPGT:
2313 case Constants.ASM_IF_ICMPLE:
2314 case Constants.ASM_IF_ACMPEQ:
2315 case Constants.ASM_IF_ACMPNE:
2316 case Constants.ASM_GOTO:
2317 case Constants.ASM_JSR:
2318 case Constants.ASM_IFNULL:
2319 case Constants.ASM_IFNONNULL:
2320 {
2321 // A forward jump with an offset > 32767. In this case we automatically replace ASM_GOTO
2322 // with GOTO_W, ASM_JSR with JSR_W and ASM_IFxxx <l> with IFNOTxxx <L> GOTO_W <l> L:...,
2323 // where IFNOTxxx is the "opposite" opcode of ASMS_IFxxx (e.g. IFNE for ASM_IFEQ) and
2324 // where <L> designates the instruction just after the GOTO_W.
2325 // First, change the ASM specific opcodes ASM_IFEQ ... ASM_JSR, ASM_IFNULL and
2326 // ASM_IFNONNULL to IFEQ ... JSR, IFNULL and IFNONNULL.
2327 opcode =
2328 opcode < Constants.ASM_IFNULL
2329 ? opcode - Constants.ASM_OPCODE_DELTA
2330 : opcode - Constants.ASM_IFNULL_OPCODE_DELTA;
2331 Label target = labels[currentBytecodeOffset + readUnsignedShort(currentOffset + 1)];
2332 if (opcode == Opcodes.GOTO || opcode == Opcodes.JSR) {
2333 // Replace GOTO with GOTO_W and JSR with JSR_W.
2334 methodVisitor.visitJumpInsn(opcode + Constants.WIDE_JUMP_OPCODE_DELTA, target);
2335 } else {
2336 // Compute the "opposite" of opcode. This can be done by flipping the least
2337 // significant bit for IFNULL and IFNONNULL, and similarly for IFEQ ... IF_ACMPEQ
2338 // (with a pre and post offset by 1).
2339 opcode = opcode < Opcodes.GOTO ? ((opcode + 1) ^ 1) - 1 : opcode ^ 1;
2340 Label endif = createLabel(currentBytecodeOffset + 3, labels);
2341 methodVisitor.visitJumpInsn(opcode, endif);
2342 methodVisitor.visitJumpInsn(Constants.GOTO_W, target);
2343 // endif designates the instruction just after GOTO_W, and is visited as part of the
2344 // next instruction. Since it is a jump target, we need to insert a frame here.
2345 insertFrame = true;
2346 }
2347 currentOffset += 3;
2348 break;
2349 }
2350 case Constants.ASM_GOTO_W:
2351 // Replace ASM_GOTO_W with GOTO_W.
2352 methodVisitor.visitJumpInsn(
2353 Constants.GOTO_W, labels[currentBytecodeOffset + readInt(currentOffset + 1)]);
2354 // The instruction just after is a jump target (because ASM_GOTO_W is used in patterns
2355 // IFNOTxxx <L> ASM_GOTO_W <l> L:..., see MethodWriter), so we need to insert a frame
2356 // here.
2357 insertFrame = true;
2358 currentOffset += 5;
2359 break;
2360 case Constants.WIDE:
2361 opcode = classBuffer[currentOffset + 1] & 0xFF;
2362 if (opcode == Opcodes.IINC) {
2363 methodVisitor.visitIincInsn(
2364 readUnsignedShort(currentOffset + 2), readShort(currentOffset + 4));
2365 currentOffset += 6;
2366 } else {
2367 methodVisitor.visitVarInsn(opcode, readUnsignedShort(currentOffset + 2));
2368 currentOffset += 4;
2369 }
2370 break;
2371 case Opcodes.TABLESWITCH:
2372 {
2373 // Skip 0 to 3 padding bytes.
2374 currentOffset += 4 - (currentBytecodeOffset & 3);
2375 // Read the instruction.
2376 Label defaultLabel = labels[currentBytecodeOffset + readInt(currentOffset)];
2377 int low = readInt(currentOffset + 4);
2378 int high = readInt(currentOffset + 8);
2379 currentOffset += 12;
2380 Label[] table = new Label[high - low + 1];
2381 for (int i = 0; i < table.length; ++i) {
2382 table[i] = labels[currentBytecodeOffset + readInt(currentOffset)];
2383 currentOffset += 4;
2384 }
2385 methodVisitor.visitTableSwitchInsn(low, high, defaultLabel, table);
2386 break;
2387 }
2388 case Opcodes.LOOKUPSWITCH:
2389 {
2390 // Skip 0 to 3 padding bytes.
2391 currentOffset += 4 - (currentBytecodeOffset & 3);
2392 // Read the instruction.
2393 Label defaultLabel = labels[currentBytecodeOffset + readInt(currentOffset)];
2394 int numPairs = readInt(currentOffset + 4);
2395 currentOffset += 8;
2396 int[] keys = new int[numPairs];
2397 Label[] values = new Label[numPairs];
2398 for (int i = 0; i < numPairs; ++i) {
2399 keys[i] = readInt(currentOffset);
2400 values[i] = labels[currentBytecodeOffset + readInt(currentOffset + 4)];
2401 currentOffset += 8;
2402 }
2403 methodVisitor.visitLookupSwitchInsn(defaultLabel, keys, values);
2404 break;
2405 }
2406 case Opcodes.ILOAD:
2407 case Opcodes.LLOAD:
2408 case Opcodes.FLOAD:
2409 case Opcodes.DLOAD:
2410 case Opcodes.ALOAD:
2411 case Opcodes.ISTORE:
2412 case Opcodes.LSTORE:
2413 case Opcodes.FSTORE:
2414 case Opcodes.DSTORE:
2415 case Opcodes.ASTORE:
2416 case Opcodes.RET:
2417 methodVisitor.visitVarInsn(opcode, classBuffer[currentOffset + 1] & 0xFF);
2418 currentOffset += 2;
2419 break;
2420 case Opcodes.BIPUSH:
2421 case Opcodes.NEWARRAY:
2422 methodVisitor.visitIntInsn(opcode, classBuffer[currentOffset + 1]);
2423 currentOffset += 2;
2424 break;
2425 case Opcodes.SIPUSH:
2426 methodVisitor.visitIntInsn(opcode, readShort(currentOffset + 1));
2427 currentOffset += 3;
2428 break;
2429 case Opcodes.LDC:
2430 methodVisitor.visitLdcInsn(readConst(classBuffer[currentOffset + 1] & 0xFF, charBuffer));
2431 currentOffset += 2;
2432 break;
2433 case Constants.LDC_W:
2434 case Constants.LDC2_W:
2435 methodVisitor.visitLdcInsn(readConst(readUnsignedShort(currentOffset + 1), charBuffer));
2436 currentOffset += 3;
2437 break;
2438 case Opcodes.GETSTATIC:
2439 case Opcodes.PUTSTATIC:
2440 case Opcodes.GETFIELD:
2441 case Opcodes.PUTFIELD:
2442 case Opcodes.INVOKEVIRTUAL:
2443 case Opcodes.INVOKESPECIAL:
2444 case Opcodes.INVOKESTATIC:
2445 case Opcodes.INVOKEINTERFACE:
2446 {
2447 int cpInfoOffset = cpInfoOffsets[readUnsignedShort(currentOffset + 1)];
2448 int nameAndTypeCpInfoOffset = cpInfoOffsets[readUnsignedShort(cpInfoOffset + 2)];
2449 String owner = readClass(cpInfoOffset, charBuffer);
2450 String name = readUTF8(nameAndTypeCpInfoOffset, charBuffer);
2451 String descriptor = readUTF8(nameAndTypeCpInfoOffset + 2, charBuffer);
2452 if (opcode < Opcodes.INVOKEVIRTUAL) {
2453 methodVisitor.visitFieldInsn(opcode, owner, name, descriptor);
2454 } else {
2455 boolean isInterface =
2456 classBuffer[cpInfoOffset - 1] == Symbol.CONSTANT_INTERFACE_METHODREF_TAG;
2457 methodVisitor.visitMethodInsn(opcode, owner, name, descriptor, isInterface);
2458 }
2459 if (opcode == Opcodes.INVOKEINTERFACE) {
2460 currentOffset += 5;
2461 } else {
2462 currentOffset += 3;
2463 }
2464 break;
2465 }
2466 case Opcodes.INVOKEDYNAMIC:
2467 {
2468 int cpInfoOffset = cpInfoOffsets[readUnsignedShort(currentOffset + 1)];
2469 int nameAndTypeCpInfoOffset = cpInfoOffsets[readUnsignedShort(cpInfoOffset + 2)];
2470 String name = readUTF8(nameAndTypeCpInfoOffset, charBuffer);
2471 String descriptor = readUTF8(nameAndTypeCpInfoOffset + 2, charBuffer);
2472 int bootstrapMethodOffset = bootstrapMethodOffsets[readUnsignedShort(cpInfoOffset)];
2473 Handle handle =
2474 (Handle) readConst(readUnsignedShort(bootstrapMethodOffset), charBuffer);
2475 Object[] bootstrapMethodArguments =
2476 new Object[readUnsignedShort(bootstrapMethodOffset + 2)];
2477 bootstrapMethodOffset += 4;
2478 for (int i = 0; i < bootstrapMethodArguments.length; i++) {
2479 bootstrapMethodArguments[i] =
2480 readConst(readUnsignedShort(bootstrapMethodOffset), charBuffer);
2481 bootstrapMethodOffset += 2;
2482 }
2483 methodVisitor.visitInvokeDynamicInsn(
2484 name, descriptor, handle, bootstrapMethodArguments);
2485 currentOffset += 5;
2486 break;
2487 }
2488 case Opcodes.NEW:
2489 case Opcodes.ANEWARRAY:
2490 case Opcodes.CHECKCAST:
2491 case Opcodes.INSTANCEOF:
2492 methodVisitor.visitTypeInsn(opcode, readClass(currentOffset + 1, charBuffer));
2493 currentOffset += 3;
2494 break;
2495 case Opcodes.IINC:
2496 methodVisitor.visitIincInsn(
2497 classBuffer[currentOffset + 1] & 0xFF, classBuffer[currentOffset + 2]);
2498 currentOffset += 3;
2499 break;
2500 case Opcodes.MULTIANEWARRAY:
2501 methodVisitor.visitMultiANewArrayInsn(
2502 readClass(currentOffset + 1, charBuffer), classBuffer[currentOffset + 3] & 0xFF);
2503 currentOffset += 4;
2504 break;
2505 default:
2506 throw new AssertionError();
2507 }
2508
2509 // Visit the runtime visible instruction annotations, if any.
2510 while (visibleTypeAnnotationOffsets != null
2511 && currentVisibleTypeAnnotationIndex < visibleTypeAnnotationOffsets.length
2512 && currentVisibleTypeAnnotationBytecodeOffset <= currentBytecodeOffset) {
2513 if (currentVisibleTypeAnnotationBytecodeOffset == currentBytecodeOffset) {
2514 // Parse the target_type, target_info and target_path fields.
2515 int currentAnnotationOffset =
2516 readTypeAnnotationTarget(
2517 context, visibleTypeAnnotationOffsets[currentVisibleTypeAnnotationIndex]);
2518 // Parse the type_index field.
2519 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
2520 currentAnnotationOffset += 2;
2521 // Parse num_element_value_pairs and element_value_pairs and visit these values.
2522 readElementValues(
2523 methodVisitor.visitInsnAnnotation(
2524 context.currentTypeAnnotationTarget,
2525 context.currentTypeAnnotationTargetPath,
2526 annotationDescriptor,
2527 /* visible = */ true),
2528 currentAnnotationOffset,
2529 /* named = */ true,
2530 charBuffer);
2531 }
2532 currentVisibleTypeAnnotationBytecodeOffset =
2533 getTypeAnnotationBytecodeOffset(
2534 visibleTypeAnnotationOffsets, ++currentVisibleTypeAnnotationIndex);
2535 }
2536
2537 // Visit the runtime invisible instruction annotations, if any.
2538 while (invisibleTypeAnnotationOffsets != null
2539 && currentInvisibleTypeAnnotationIndex < invisibleTypeAnnotationOffsets.length
2540 && currentInvisibleTypeAnnotationBytecodeOffset <= currentBytecodeOffset) {
2541 if (currentInvisibleTypeAnnotationBytecodeOffset == currentBytecodeOffset) {
2542 // Parse the target_type, target_info and target_path fields.
2543 int currentAnnotationOffset =
2544 readTypeAnnotationTarget(
2545 context, invisibleTypeAnnotationOffsets[currentInvisibleTypeAnnotationIndex]);
2546 // Parse the type_index field.
2547 String annotationDescriptor = readUTF8(currentAnnotationOffset, charBuffer);
2548 currentAnnotationOffset += 2;
2549 // Parse num_element_value_pairs and element_value_pairs and visit these values.
2550 readElementValues(
2551 methodVisitor.visitInsnAnnotation(
2552 context.currentTypeAnnotationTarget,
2553 context.currentTypeAnnotationTargetPath,
2554 annotationDescriptor,
2555 /* visible = */ false),
2556 currentAnnotationOffset,
2557 /* named = */ true,
2558 charBuffer);
2559 }
2560 currentInvisibleTypeAnnotationBytecodeOffset =
2561 getTypeAnnotationBytecodeOffset(
2562 invisibleTypeAnnotationOffsets, ++currentInvisibleTypeAnnotationIndex);
2563 }
2564 }
2565 if (labels[codeLength] != null) {
2566 methodVisitor.visitLabel(labels[codeLength]);
2567 }
2568
2569 // Visit LocalVariableTable and LocalVariableTypeTable attributes.
2570 if (localVariableTableOffset != 0 && (context.parsingOptions & SKIP_DEBUG) == 0) {
2571 // The (start_pc, index, signature_index) fields of each entry of the LocalVariableTypeTable.
2572 int[] typeTable = null;
2573 if (localVariableTypeTableOffset != 0) {
2574 typeTable = new int[readUnsignedShort(localVariableTypeTableOffset) * 3];
2575 currentOffset = localVariableTypeTableOffset + 2;
2576 int typeTableIndex = typeTable.length;
2577 while (typeTableIndex > 0) {
2578 // Store the offset of 'signature_index', and the value of 'index' and 'start_pc'.
2579 typeTable[--typeTableIndex] = currentOffset + 6;
2580 typeTable[--typeTableIndex] = readUnsignedShort(currentOffset + 8);
2581 typeTable[--typeTableIndex] = readUnsignedShort(currentOffset);
2582 currentOffset += 10;
2583 }
2584 }
2585 int localVariableTableLength = readUnsignedShort(localVariableTableOffset);
2586 currentOffset = localVariableTableOffset + 2;
2587 while (localVariableTableLength-- > 0) {
2588 int startPc = readUnsignedShort(currentOffset);
2589 int length = readUnsignedShort(currentOffset + 2);
2590 String name = readUTF8(currentOffset + 4, charBuffer);
2591 String descriptor = readUTF8(currentOffset + 6, charBuffer);
2592 int index = readUnsignedShort(currentOffset + 8);
2593 currentOffset += 10;
2594 String signature = null;
2595 if (typeTable != null) {
2596 for (int i = 0; i < typeTable.length; i += 3) {
2597 if (typeTable[i] == startPc && typeTable[i + 1] == index) {
2598 signature = readUTF8(typeTable[i + 2], charBuffer);
2599 break;
2600 }
2601 }
2602 }
2603 methodVisitor.visitLocalVariable(
2604 name, descriptor, signature, labels[startPc], labels[startPc + length], index);
2605 }
2606 }
2607
2608 // Visit the local variable type annotations of the RuntimeVisibleTypeAnnotations attribute.
2609 if (visibleTypeAnnotationOffsets != null) {
2610 for (int typeAnnotationOffset : visibleTypeAnnotationOffsets) {
2611 int targetType = readByte(typeAnnotationOffset);
2612 if (targetType == TypeReference.LOCAL_VARIABLE
2613 || targetType == TypeReference.RESOURCE_VARIABLE) {
2614 // Parse the target_type, target_info and target_path fields.
2615 currentOffset = readTypeAnnotationTarget(context, typeAnnotationOffset);
2616 // Parse the type_index field.
2617 String annotationDescriptor = readUTF8(currentOffset, charBuffer);
2618 currentOffset += 2;
2619 // Parse num_element_value_pairs and element_value_pairs and visit these values.
2620 readElementValues(
2621 methodVisitor.visitLocalVariableAnnotation(
2622 context.currentTypeAnnotationTarget,
2623 context.currentTypeAnnotationTargetPath,
2624 context.currentLocalVariableAnnotationRangeStarts,
2625 context.currentLocalVariableAnnotationRangeEnds,
2626 context.currentLocalVariableAnnotationRangeIndices,
2627 annotationDescriptor,
2628 /* visible = */ true),
2629 currentOffset,
2630 /* named = */ true,
2631 charBuffer);
2632 }
2633 }
2634 }
2635
2636 // Visit the local variable type annotations of the RuntimeInvisibleTypeAnnotations attribute.
2637 if (invisibleTypeAnnotationOffsets != null) {
2638 for (int typeAnnotationOffset : invisibleTypeAnnotationOffsets) {
2639 int targetType = readByte(typeAnnotationOffset);
2640 if (targetType == TypeReference.LOCAL_VARIABLE
2641 || targetType == TypeReference.RESOURCE_VARIABLE) {
2642 // Parse the target_type, target_info and target_path fields.
2643 currentOffset = readTypeAnnotationTarget(context, typeAnnotationOffset);
2644 // Parse the type_index field.
2645 String annotationDescriptor = readUTF8(currentOffset, charBuffer);
2646 currentOffset += 2;
2647 // Parse num_element_value_pairs and element_value_pairs and visit these values.
2648 readElementValues(
2649 methodVisitor.visitLocalVariableAnnotation(
2650 context.currentTypeAnnotationTarget,
2651 context.currentTypeAnnotationTargetPath,
2652 context.currentLocalVariableAnnotationRangeStarts,
2653 context.currentLocalVariableAnnotationRangeEnds,
2654 context.currentLocalVariableAnnotationRangeIndices,
2655 annotationDescriptor,
2656 /* visible = */ false),
2657 currentOffset,
2658 /* named = */ true,
2659 charBuffer);
2660 }
2661 }
2662 }
2663
2664 // Visit the non standard attributes.
2665 while (attributes != null) {
2666 // Copy and reset the nextAttribute field so that it can also be used in MethodWriter.
2667 Attribute nextAttribute = attributes.nextAttribute;
2668 attributes.nextAttribute = null;
2669 methodVisitor.visitAttribute(attributes);
2670 attributes = nextAttribute;
2671 }
2672
2673 // Visit the max stack and max locals values.
2674 methodVisitor.visitMaxs(maxStack, maxLocals);
2675 }
2676
2677 /**
2678 * Returns the label corresponding to the given bytecode offset. The default implementation of
2679 * this method creates a label for the given offset if it has not been already created.
2680 *
2681 * @param bytecodeOffset a bytecode offset in a method.
2682 * @param labels the already created labels, indexed by their offset. If a label already exists
2683 * for bytecodeOffset this method must not create a new one. Otherwise it must store the new
2684 * label in this array.
2685 * @return a non null Label, which must be equal to labels[bytecodeOffset].
2686 */
2687 protected Label readLabel(final int bytecodeOffset, final Label[] labels) {
2688 if (labels[bytecodeOffset] == null) {
2689 labels[bytecodeOffset] = new Label();
2690 }
2691 return labels[bytecodeOffset];
2692 }
2693
2694 /**
2695 * Creates a label without the {@link Label#FLAG_DEBUG_ONLY} flag set, for the given bytecode
2696 * offset. The label is created with a call to {@link #readLabel} and its {@link
2697 * Label#FLAG_DEBUG_ONLY} flag is cleared.
2698 *
2699 * @param bytecodeOffset a bytecode offset in a method.
2700 * @param labels the already created labels, indexed by their offset.
2701 * @return a Label without the {@link Label#FLAG_DEBUG_ONLY} flag set.
2702 */
2703 private Label createLabel(final int bytecodeOffset, final Label[] labels) {
2704 Label label = readLabel(bytecodeOffset, labels);
2705 label.flags &= ~Label.FLAG_DEBUG_ONLY;
2706 return label;
2707 }
2708
2709 /**
2710 * Creates a label with the {@link Label#FLAG_DEBUG_ONLY} flag set, if there is no already
2711 * existing label for the given bytecode offset (otherwise does nothing). The label is created
2712 * with a call to {@link #readLabel}.
2713 *
2714 * @param bytecodeOffset a bytecode offset in a method.
2715 * @param labels the already created labels, indexed by their offset.
2716 */
2717 private void createDebugLabel(final int bytecodeOffset, final Label[] labels) {
2718 if (labels[bytecodeOffset] == null) {
2719 readLabel(bytecodeOffset, labels).flags |= Label.FLAG_DEBUG_ONLY;
2720 }
2721 }
2722
2723 // ----------------------------------------------------------------------------------------------
2724 // Methods to parse annotations, type annotations and parameter annotations
2725 // ----------------------------------------------------------------------------------------------
2726
2727 /**
2728 * Parses a Runtime[In]VisibleTypeAnnotations attribute to find the offset of each type_annotation
2729 * entry it contains, to find the corresponding labels, and to visit the try catch block
2730 * annotations.
2731 *
2732 * @param methodVisitor the method visitor to be used to visit the try catch block annotations.
2733 * @param context information about the class being parsed.
2734 * @param runtimeTypeAnnotationsOffset the start offset of a Runtime[In]VisibleTypeAnnotations
2735 * attribute, excluding the attribute_info's attribute_name_index and attribute_length fields.
2736 * @param visible true if the attribute to parse is a RuntimeVisibleTypeAnnotations attribute,
2737 * false it is a RuntimeInvisibleTypeAnnotations attribute.
2738 * @return the start offset of each entry of the Runtime[In]VisibleTypeAnnotations_attribute's
2739 * 'annotations' array field.
2740 */
2741 private int[] readTypeAnnotations(
2742 final MethodVisitor methodVisitor,
2743 final Context context,
2744 final int runtimeTypeAnnotationsOffset,
2745 final boolean visible) {
2746 char[] charBuffer = context.charBuffer;
2747 int currentOffset = runtimeTypeAnnotationsOffset;
2748 // Read the num_annotations field and create an array to store the type_annotation offsets.
2749 int[] typeAnnotationsOffsets = new int[readUnsignedShort(currentOffset)];
2750 currentOffset += 2;
2751 // Parse the 'annotations' array field.
2752 for (int i = 0; i < typeAnnotationsOffsets.length; ++i) {
2753 typeAnnotationsOffsets[i] = currentOffset;
2754 // Parse the type_annotation's target_type and the target_info fields. The size of the
2755 // target_info field depends on the value of target_type.
2756 int targetType = readInt(currentOffset);
2757 switch (targetType >>> 24) {
2758 case TypeReference.LOCAL_VARIABLE:
2759 case TypeReference.RESOURCE_VARIABLE:
2760 // A localvar_target has a variable size, which depends on the value of their table_length
2761 // field. It also references bytecode offsets, for which we need labels.
2762 int tableLength = readUnsignedShort(currentOffset + 1);
2763 currentOffset += 3;
2764 while (tableLength-- > 0) {
2765 int startPc = readUnsignedShort(currentOffset);
2766 int length = readUnsignedShort(currentOffset + 2);
2767 // Skip the index field (2 bytes).
2768 currentOffset += 6;
2769 createLabel(startPc, context.currentMethodLabels);
2770 createLabel(startPc + length, context.currentMethodLabels);
2771 }
2772 break;
2773 case TypeReference.CAST:
2774 case TypeReference.CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT:
2775 case TypeReference.METHOD_INVOCATION_TYPE_ARGUMENT:
2776 case TypeReference.CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT:
2777 case TypeReference.METHOD_REFERENCE_TYPE_ARGUMENT:
2778 currentOffset += 4;
2779 break;
2780 case TypeReference.CLASS_EXTENDS:
2781 case TypeReference.CLASS_TYPE_PARAMETER_BOUND:
2782 case TypeReference.METHOD_TYPE_PARAMETER_BOUND:
2783 case TypeReference.THROWS:
2784 case TypeReference.EXCEPTION_PARAMETER:
2785 case TypeReference.INSTANCEOF:
2786 case TypeReference.NEW:
2787 case TypeReference.CONSTRUCTOR_REFERENCE:
2788 case TypeReference.METHOD_REFERENCE:
2789 currentOffset += 3;
2790 break;
2791 case TypeReference.CLASS_TYPE_PARAMETER:
2792 case TypeReference.METHOD_TYPE_PARAMETER:
2793 case TypeReference.METHOD_FORMAL_PARAMETER:
2794 case TypeReference.FIELD:
2795 case TypeReference.METHOD_RETURN:
2796 case TypeReference.METHOD_RECEIVER:
2797 default:
2798 // TypeReference type which can't be used in Code attribute, or which is unknown.
2799 throw new IllegalArgumentException();
2800 }
2801 // Parse the rest of the type_annotation structure, starting with the target_path structure
2802 // (whose size depends on its path_length field).
2803 int pathLength = readByte(currentOffset);
2804 if ((targetType >>> 24) == TypeReference.EXCEPTION_PARAMETER) {
2805 // Parse the target_path structure and create a corresponding TypePath.
2806 TypePath path = pathLength == 0 ? null : new TypePath(classFileBuffer, currentOffset);
2807 currentOffset += 1 + 2 * pathLength;
2808 // Parse the type_index field.
2809 String annotationDescriptor = readUTF8(currentOffset, charBuffer);
2810 currentOffset += 2;
2811 // Parse num_element_value_pairs and element_value_pairs and visit these values.
2812 currentOffset =
2813 readElementValues(
2814 methodVisitor.visitTryCatchAnnotation(
2815 targetType & 0xFFFFFF00, path, annotationDescriptor, visible),
2816 currentOffset,
2817 /* named = */ true,
2818 charBuffer);
2819 } else {
2820 // We don't want to visit the other target_type annotations, so we just skip them (which
2821 // requires some parsing because the element_value_pairs array has a variable size). First,
2822 // skip the target_path structure:
2823 currentOffset += 3 + 2 * pathLength;
2824 // Then skip the num_element_value_pairs and element_value_pairs fields (by reading them
2825 // with a null AnnotationVisitor).
2826 currentOffset =
2827 readElementValues(
2828 /* annotationVisitor = */ null, currentOffset, /* named = */ true, charBuffer);
2829 }
2830 }
2831 return typeAnnotationsOffsets;
2832 }
2833
2834 /**
2835 * Returns the bytecode offset corresponding to the specified JVMS 'type_annotation' structure, or
2836 * -1 if there is no such type_annotation of if it does not have a bytecode offset.
2837 *
2838 * @param typeAnnotationOffsets the offset of each 'type_annotation' entry in a
2839 * Runtime[In]VisibleTypeAnnotations attribute, or {@literal null}.
2840 * @param typeAnnotationIndex the index a 'type_annotation' entry in typeAnnotationOffsets.
2841 * @return bytecode offset corresponding to the specified JVMS 'type_annotation' structure, or -1
2842 * if there is no such type_annotation of if it does not have a bytecode offset.
2843 */
2844 private int getTypeAnnotationBytecodeOffset(
2845 final int[] typeAnnotationOffsets, final int typeAnnotationIndex) {
2846 if (typeAnnotationOffsets == null
2847 || typeAnnotationIndex >= typeAnnotationOffsets.length
2848 || readByte(typeAnnotationOffsets[typeAnnotationIndex]) < TypeReference.INSTANCEOF) {
2849 return -1;
2850 }
2851 return readUnsignedShort(typeAnnotationOffsets[typeAnnotationIndex] + 1);
2852 }
2853
2854 /**
2855 * Parses the header of a JVMS type_annotation structure to extract its target_type, target_info
2856 * and target_path (the result is stored in the given context), and returns the start offset of
2857 * the rest of the type_annotation structure.
2858 *
2859 * @param context information about the class being parsed. This is where the extracted
2860 * target_type and target_path must be stored.
2861 * @param typeAnnotationOffset the start offset of a type_annotation structure.
2862 * @return the start offset of the rest of the type_annotation structure.
2863 */
2864 private int readTypeAnnotationTarget(final Context context, final int typeAnnotationOffset) {
2865 int currentOffset = typeAnnotationOffset;
2866 // Parse and store the target_type structure.
2867 int targetType = readInt(typeAnnotationOffset);
2868 switch (targetType >>> 24) {
2869 case TypeReference.CLASS_TYPE_PARAMETER:
2870 case TypeReference.METHOD_TYPE_PARAMETER:
2871 case TypeReference.METHOD_FORMAL_PARAMETER:
2872 targetType &= 0xFFFF0000;
2873 currentOffset += 2;
2874 break;
2875 case TypeReference.FIELD:
2876 case TypeReference.METHOD_RETURN:
2877 case TypeReference.METHOD_RECEIVER:
2878 targetType &= 0xFF000000;
2879 currentOffset += 1;
2880 break;
2881 case TypeReference.LOCAL_VARIABLE:
2882 case TypeReference.RESOURCE_VARIABLE:
2883 targetType &= 0xFF000000;
2884 int tableLength = readUnsignedShort(currentOffset + 1);
2885 currentOffset += 3;
2886 context.currentLocalVariableAnnotationRangeStarts = new Label[tableLength];
2887 context.currentLocalVariableAnnotationRangeEnds = new Label[tableLength];
2888 context.currentLocalVariableAnnotationRangeIndices = new int[tableLength];
2889 for (int i = 0; i < tableLength; ++i) {
2890 int startPc = readUnsignedShort(currentOffset);
2891 int length = readUnsignedShort(currentOffset + 2);
2892 int index = readUnsignedShort(currentOffset + 4);
2893 currentOffset += 6;
2894 context.currentLocalVariableAnnotationRangeStarts[i] =
2895 createLabel(startPc, context.currentMethodLabels);
2896 context.currentLocalVariableAnnotationRangeEnds[i] =
2897 createLabel(startPc + length, context.currentMethodLabels);
2898 context.currentLocalVariableAnnotationRangeIndices[i] = index;
2899 }
2900 break;
2901 case TypeReference.CAST:
2902 case TypeReference.CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT:
2903 case TypeReference.METHOD_INVOCATION_TYPE_ARGUMENT:
2904 case TypeReference.CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT:
2905 case TypeReference.METHOD_REFERENCE_TYPE_ARGUMENT:
2906 targetType &= 0xFF0000FF;
2907 currentOffset += 4;
2908 break;
2909 case TypeReference.CLASS_EXTENDS:
2910 case TypeReference.CLASS_TYPE_PARAMETER_BOUND:
2911 case TypeReference.METHOD_TYPE_PARAMETER_BOUND:
2912 case TypeReference.THROWS:
2913 case TypeReference.EXCEPTION_PARAMETER:
2914 targetType &= 0xFFFFFF00;
2915 currentOffset += 3;
2916 break;
2917 case TypeReference.INSTANCEOF:
2918 case TypeReference.NEW:
2919 case TypeReference.CONSTRUCTOR_REFERENCE:
2920 case TypeReference.METHOD_REFERENCE:
2921 targetType &= 0xFF000000;
2922 currentOffset += 3;
2923 break;
2924 default:
2925 throw new IllegalArgumentException();
2926 }
2927 context.currentTypeAnnotationTarget = targetType;
2928 // Parse and store the target_path structure.
2929 int pathLength = readByte(currentOffset);
2930 context.currentTypeAnnotationTargetPath =
2931 pathLength == 0 ? null : new TypePath(classFileBuffer, currentOffset);
2932 // Return the start offset of the rest of the type_annotation structure.
2933 return currentOffset + 1 + 2 * pathLength;
2934 }
2935
2936 /**
2937 * Reads a Runtime[In]VisibleParameterAnnotations attribute and makes the given visitor visit it.
2938 *
2939 * @param methodVisitor the visitor that must visit the parameter annotations.
2940 * @param context information about the class being parsed.
2941 * @param runtimeParameterAnnotationsOffset the start offset of a
2942 * Runtime[In]VisibleParameterAnnotations attribute, excluding the attribute_info's
2943 * attribute_name_index and attribute_length fields.
2944 * @param visible true if the attribute to parse is a RuntimeVisibleParameterAnnotations
2945 * attribute, false it is a RuntimeInvisibleParameterAnnotations attribute.
2946 */
2947 private void readParameterAnnotations(
2948 final MethodVisitor methodVisitor,
2949 final Context context,
2950 final int runtimeParameterAnnotationsOffset,
2951 final boolean visible) {
2952 int currentOffset = runtimeParameterAnnotationsOffset;
2953 int numParameters = classFileBuffer[currentOffset++] & 0xFF;
2954 methodVisitor.visitAnnotableParameterCount(numParameters, visible);
2955 char[] charBuffer = context.charBuffer;
2956 for (int i = 0; i < numParameters; ++i) {
2957 int numAnnotations = readUnsignedShort(currentOffset);
2958 currentOffset += 2;
2959 while (numAnnotations-- > 0) {
2960 // Parse the type_index field.
2961 String annotationDescriptor = readUTF8(currentOffset, charBuffer);
2962 currentOffset += 2;
2963 // Parse num_element_value_pairs and element_value_pairs and visit these values.
2964 currentOffset =
2965 readElementValues(
2966 methodVisitor.visitParameterAnnotation(i, annotationDescriptor, visible),
2967 currentOffset,
2968 /* named = */ true,
2969 charBuffer);
2970 }
2971 }
2972 }
2973
2974 /**
2975 * Reads the element values of a JVMS 'annotation' structure and makes the given visitor visit
2976 * them. This method can also be used to read the values of the JVMS 'array_value' field of an
2977 * annotation's 'element_value'.
2978 *
2979 * @param annotationVisitor the visitor that must visit the values.
2980 * @param annotationOffset the start offset of an 'annotation' structure (excluding its type_index
2981 * field) or of an 'array_value' structure.
2982 * @param named if the annotation values are named or not. This should be true to parse the values
2983 * of a JVMS 'annotation' structure, and false to parse the JVMS 'array_value' of an
2984 * annotation's element_value.
2985 * @param charBuffer the buffer used to read strings in the constant pool.
2986 * @return the end offset of the JVMS 'annotation' or 'array_value' structure.
2987 */
2988 private int readElementValues(
2989 final AnnotationVisitor annotationVisitor,
2990 final int annotationOffset,
2991 final boolean named,
2992 final char[] charBuffer) {
2993 int currentOffset = annotationOffset;
2994 // Read the num_element_value_pairs field (or num_values field for an array_value).
2995 int numElementValuePairs = readUnsignedShort(currentOffset);
2996 currentOffset += 2;
2997 if (named) {
2998 // Parse the element_value_pairs array.
2999 while (numElementValuePairs-- > 0) {
3000 String elementName = readUTF8(currentOffset, charBuffer);
3001 currentOffset =
3002 readElementValue(annotationVisitor, currentOffset + 2, elementName, charBuffer);
3003 }
3004 } else {
3005 // Parse the array_value array.
3006 while (numElementValuePairs-- > 0) {
3007 currentOffset =
3008 readElementValue(annotationVisitor, currentOffset, /* named = */ null, charBuffer);
3009 }
3010 }
3011 if (annotationVisitor != null) {
3012 annotationVisitor.visitEnd();
3013 }
3014 return currentOffset;
3015 }
3016
3017 /**
3018 * Reads a JVMS 'element_value' structure and makes the given visitor visit it.
3019 *
3020 * @param annotationVisitor the visitor that must visit the element_value structure.
3021 * @param elementValueOffset the start offset in {@link #classFileBuffer} of the element_value
3022 * structure to be read.
3023 * @param elementName the name of the element_value structure to be read, or {@literal null}.
3024 * @param charBuffer the buffer used to read strings in the constant pool.
3025 * @return the end offset of the JVMS 'element_value' structure.
3026 */
3027 private int readElementValue(
3028 final AnnotationVisitor annotationVisitor,
3029 final int elementValueOffset,
3030 final String elementName,
3031 final char[] charBuffer) {
3032 int currentOffset = elementValueOffset;
3033 if (annotationVisitor == null) {
3034 switch (classFileBuffer[currentOffset] & 0xFF) {
3035 case 'e': // enum_const_value
3036 return currentOffset + 5;
3037 case '@': // annotation_value
3038 return readElementValues(null, currentOffset + 3, /* named = */ true, charBuffer);
3039 case '[': // array_value
3040 return readElementValues(null, currentOffset + 1, /* named = */ false, charBuffer);
3041 default:
3042 return currentOffset + 3;
3043 }
3044 }
3045 switch (classFileBuffer[currentOffset++] & 0xFF) {
3046 case 'B': // const_value_index, CONSTANT_Integer
3047 annotationVisitor.visit(
3048 elementName, (byte) readInt(cpInfoOffsets[readUnsignedShort(currentOffset)]));
3049 currentOffset += 2;
3050 break;
3051 case 'C': // const_value_index, CONSTANT_Integer
3052 annotationVisitor.visit(
3053 elementName, (char) readInt(cpInfoOffsets[readUnsignedShort(currentOffset)]));
3054 currentOffset += 2;
3055 break;
3056 case 'D': // const_value_index, CONSTANT_Double
3057 case 'F': // const_value_index, CONSTANT_Float
3058 case 'I': // const_value_index, CONSTANT_Integer
3059 case 'J': // const_value_index, CONSTANT_Long
3060 annotationVisitor.visit(
3061 elementName, readConst(readUnsignedShort(currentOffset), charBuffer));
3062 currentOffset += 2;
3063 break;
3064 case 'S': // const_value_index, CONSTANT_Integer
3065 annotationVisitor.visit(
3066 elementName, (short) readInt(cpInfoOffsets[readUnsignedShort(currentOffset)]));
3067 currentOffset += 2;
3068 break;
3069
3070 case 'Z': // const_value_index, CONSTANT_Integer
3071 annotationVisitor.visit(
3072 elementName,
3073 readInt(cpInfoOffsets[readUnsignedShort(currentOffset)]) == 0
3074 ? Boolean.FALSE
3075 : Boolean.TRUE);
3076 currentOffset += 2;
3077 break;
3078 case 's': // const_value_index, CONSTANT_Utf8
3079 annotationVisitor.visit(elementName, readUTF8(currentOffset, charBuffer));
3080 currentOffset += 2;
3081 break;
3082 case 'e': // enum_const_value
3083 annotationVisitor.visitEnum(
3084 elementName,
3085 readUTF8(currentOffset, charBuffer),
3086 readUTF8(currentOffset + 2, charBuffer));
3087 currentOffset += 4;
3088 break;
3089 case 'c': // class_info
3090 annotationVisitor.visit(elementName, Type.getType(readUTF8(currentOffset, charBuffer)));
3091 currentOffset += 2;
3092 break;
3093 case '@': // annotation_value
3094 currentOffset =
3095 readElementValues(
3096 annotationVisitor.visitAnnotation(elementName, readUTF8(currentOffset, charBuffer)),
3097 currentOffset + 2,
3098 true,
3099 charBuffer);
3100 break;
3101 case '[': // array_value
3102 int numValues = readUnsignedShort(currentOffset);
3103 currentOffset += 2;
3104 if (numValues == 0) {
3105 return readElementValues(
3106 annotationVisitor.visitArray(elementName),
3107 currentOffset - 2,
3108 /* named = */ false,
3109 charBuffer);
3110 }
3111 switch (classFileBuffer[currentOffset] & 0xFF) {
3112 case 'B':
3113 byte[] byteValues = new byte[numValues];
3114 for (int i = 0; i < numValues; i++) {
3115 byteValues[i] = (byte) readInt(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]);
3116 currentOffset += 3;
3117 }
3118 annotationVisitor.visit(elementName, byteValues);
3119 break;
3120 case 'Z':
3121 boolean[] booleanValues = new boolean[numValues];
3122 for (int i = 0; i < numValues; i++) {
3123 booleanValues[i] = readInt(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]) != 0;
3124 currentOffset += 3;
3125 }
3126 annotationVisitor.visit(elementName, booleanValues);
3127 break;
3128 case 'S':
3129 short[] shortValues = new short[numValues];
3130 for (int i = 0; i < numValues; i++) {
3131 shortValues[i] = (short) readInt(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]);
3132 currentOffset += 3;
3133 }
3134 annotationVisitor.visit(elementName, shortValues);
3135 break;
3136 case 'C':
3137 char[] charValues = new char[numValues];
3138 for (int i = 0; i < numValues; i++) {
3139 charValues[i] = (char) readInt(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]);
3140 currentOffset += 3;
3141 }
3142 annotationVisitor.visit(elementName, charValues);
3143 break;
3144 case 'I':
3145 int[] intValues = new int[numValues];
3146 for (int i = 0; i < numValues; i++) {
3147 intValues[i] = readInt(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]);
3148 currentOffset += 3;
3149 }
3150 annotationVisitor.visit(elementName, intValues);
3151 break;
3152 case 'J':
3153 long[] longValues = new long[numValues];
3154 for (int i = 0; i < numValues; i++) {
3155 longValues[i] = readLong(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]);
3156 currentOffset += 3;
3157 }
3158 annotationVisitor.visit(elementName, longValues);
3159 break;
3160 case 'F':
3161 float[] floatValues = new float[numValues];
3162 for (int i = 0; i < numValues; i++) {
3163 floatValues[i] =
3164 Float.intBitsToFloat(
3165 readInt(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]));
3166 currentOffset += 3;
3167 }
3168 annotationVisitor.visit(elementName, floatValues);
3169 break;
3170 case 'D':
3171 double[] doubleValues = new double[numValues];
3172 for (int i = 0; i < numValues; i++) {
3173 doubleValues[i] =
3174 Double.longBitsToDouble(
3175 readLong(cpInfoOffsets[readUnsignedShort(currentOffset + 1)]));
3176 currentOffset += 3;
3177 }
3178 annotationVisitor.visit(elementName, doubleValues);
3179 break;
3180 default:
3181 currentOffset =
3182 readElementValues(
3183 annotationVisitor.visitArray(elementName),
3184 currentOffset - 2,
3185 /* named = */ false,
3186 charBuffer);
3187 break;
3188 }
3189 break;
3190 default:
3191 throw new IllegalArgumentException();
3192 }
3193 return currentOffset;
3194 }
3195
3196 // ----------------------------------------------------------------------------------------------
3197 // Methods to parse stack map frames
3198 // ----------------------------------------------------------------------------------------------
3199
3200 /**
3201 * Computes the implicit frame of the method currently being parsed (as defined in the given
3202 * {@link Context}) and stores it in the given context.
3203 *
3204 * @param context information about the class being parsed.
3205 */
3206 private void computeImplicitFrame(final Context context) {
3207 String methodDescriptor = context.currentMethodDescriptor;
3208 Object[] locals = context.currentFrameLocalTypes;
3209 int numLocal = 0;
3210 if ((context.currentMethodAccessFlags & Opcodes.ACC_STATIC) == 0) {
3211 if ("<init>".equals(context.currentMethodName)) {
3212 locals[numLocal++] = Opcodes.UNINITIALIZED_THIS;
3213 } else {
3214 locals[numLocal++] = readClass(header + 2, context.charBuffer);
3215 }
3216 }
3217 // Parse the method descriptor, one argument type descriptor at each iteration. Start by
3218 // skipping the first method descriptor character, which is always '('.
3219 int currentMethodDescritorOffset = 1;
3220 while (true) {
3221 int currentArgumentDescriptorStartOffset = currentMethodDescritorOffset;
3222 switch (methodDescriptor.charAt(currentMethodDescritorOffset++)) {
3223 case 'Z':
3224 case 'C':
3225 case 'B':
3226 case 'S':
3227 case 'I':
3228 locals[numLocal++] = Opcodes.INTEGER;
3229 break;
3230 case 'F':
3231 locals[numLocal++] = Opcodes.FLOAT;
3232 break;
3233 case 'J':
3234 locals[numLocal++] = Opcodes.LONG;
3235 break;
3236 case 'D':
3237 locals[numLocal++] = Opcodes.DOUBLE;
3238 break;
3239 case '[':
3240 while (methodDescriptor.charAt(currentMethodDescritorOffset) == '[') {
3241 ++currentMethodDescritorOffset;
3242 }
3243 if (methodDescriptor.charAt(currentMethodDescritorOffset) == 'L') {
3244 ++currentMethodDescritorOffset;
3245 while (methodDescriptor.charAt(currentMethodDescritorOffset) != ';') {
3246 ++currentMethodDescritorOffset;
3247 }
3248 }
3249 locals[numLocal++] =
3250 methodDescriptor.substring(
3251 currentArgumentDescriptorStartOffset, ++currentMethodDescritorOffset);
3252 break;
3253 case 'L':
3254 while (methodDescriptor.charAt(currentMethodDescritorOffset) != ';') {
3255 ++currentMethodDescritorOffset;
3256 }
3257 locals[numLocal++] =
3258 methodDescriptor.substring(
3259 currentArgumentDescriptorStartOffset + 1, currentMethodDescritorOffset++);
3260 break;
3261 default:
3262 context.currentFrameLocalCount = numLocal;
3263 return;
3264 }
3265 }
3266 }
3267
3268 /**
3269 * Reads a JVMS 'stack_map_frame' structure and stores the result in the given {@link Context}
3270 * object. This method can also be used to read a full_frame structure, excluding its frame_type
3271 * field (this is used to parse the legacy StackMap attributes).
3272 *
3273 * @param stackMapFrameOffset the start offset in {@link #classFileBuffer} of the
3274 * stack_map_frame_value structure to be read, or the start offset of a full_frame structure
3275 * (excluding its frame_type field).
3276 * @param compressed true to read a 'stack_map_frame' structure, false to read a 'full_frame'
3277 * structure without its frame_type field.
3278 * @param expand if the stack map frame must be expanded. See {@link #EXPAND_FRAMES}.
3279 * @param context where the parsed stack map frame must be stored.
3280 * @return the end offset of the JVMS 'stack_map_frame' or 'full_frame' structure.
3281 */
3282 private int readStackMapFrame(
3283 final int stackMapFrameOffset,
3284 final boolean compressed,
3285 final boolean expand,
3286 final Context context) {
3287 int currentOffset = stackMapFrameOffset;
3288 final char[] charBuffer = context.charBuffer;
3289 final Label[] labels = context.currentMethodLabels;
3290 int frameType;
3291 if (compressed) {
3292 // Read the frame_type field.
3293 frameType = classFileBuffer[currentOffset++] & 0xFF;
3294 } else {
3295 frameType = Frame.FULL_FRAME;
3296 context.currentFrameOffset = -1;
3297 }
3298 int offsetDelta;
3299 context.currentFrameLocalCountDelta = 0;
3300 if (frameType < Frame.SAME_LOCALS_1_STACK_ITEM_FRAME) {
3301 offsetDelta = frameType;
3302 context.currentFrameType = Opcodes.F_SAME;
3303 context.currentFrameStackCount = 0;
3304 } else if (frameType < Frame.RESERVED) {
3305 offsetDelta = frameType - Frame.SAME_LOCALS_1_STACK_ITEM_FRAME;
3306 currentOffset =
3307 readVerificationTypeInfo(
3308 currentOffset, context.currentFrameStackTypes, 0, charBuffer, labels);
3309 context.currentFrameType = Opcodes.F_SAME1;
3310 context.currentFrameStackCount = 1;
3311 } else if (frameType >= Frame.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) {
3312 offsetDelta = readUnsignedShort(currentOffset);
3313 currentOffset += 2;
3314 if (frameType == Frame.SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) {
3315 currentOffset =
3316 readVerificationTypeInfo(
3317 currentOffset, context.currentFrameStackTypes, 0, charBuffer, labels);
3318 context.currentFrameType = Opcodes.F_SAME1;
3319 context.currentFrameStackCount = 1;
3320 } else if (frameType >= Frame.CHOP_FRAME && frameType < Frame.SAME_FRAME_EXTENDED) {
3321 context.currentFrameType = Opcodes.F_CHOP;
3322 context.currentFrameLocalCountDelta = Frame.SAME_FRAME_EXTENDED - frameType;
3323 context.currentFrameLocalCount -= context.currentFrameLocalCountDelta;
3324 context.currentFrameStackCount = 0;
3325 } else if (frameType == Frame.SAME_FRAME_EXTENDED) {
3326 context.currentFrameType = Opcodes.F_SAME;
3327 context.currentFrameStackCount = 0;
3328 } else if (frameType < Frame.FULL_FRAME) {
3329 int local = expand ? context.currentFrameLocalCount : 0;
3330 for (int k = frameType - Frame.SAME_FRAME_EXTENDED; k > 0; k--) {
3331 currentOffset =
3332 readVerificationTypeInfo(
3333 currentOffset, context.currentFrameLocalTypes, local++, charBuffer, labels);
3334 }
3335 context.currentFrameType = Opcodes.F_APPEND;
3336 context.currentFrameLocalCountDelta = frameType - Frame.SAME_FRAME_EXTENDED;
3337 context.currentFrameLocalCount += context.currentFrameLocalCountDelta;
3338 context.currentFrameStackCount = 0;
3339 } else {
3340 final int numberOfLocals = readUnsignedShort(currentOffset);
3341 currentOffset += 2;
3342 context.currentFrameType = Opcodes.F_FULL;
3343 context.currentFrameLocalCountDelta = numberOfLocals;
3344 context.currentFrameLocalCount = numberOfLocals;
3345 for (int local = 0; local < numberOfLocals; ++local) {
3346 currentOffset =
3347 readVerificationTypeInfo(
3348 currentOffset, context.currentFrameLocalTypes, local, charBuffer, labels);
3349 }
3350 final int numberOfStackItems = readUnsignedShort(currentOffset);
3351 currentOffset += 2;
3352 context.currentFrameStackCount = numberOfStackItems;
3353 for (int stack = 0; stack < numberOfStackItems; ++stack) {
3354 currentOffset =
3355 readVerificationTypeInfo(
3356 currentOffset, context.currentFrameStackTypes, stack, charBuffer, labels);
3357 }
3358 }
3359 } else {
3360 throw new IllegalArgumentException();
3361 }
3362 context.currentFrameOffset += offsetDelta + 1;
3363 createLabel(context.currentFrameOffset, labels);
3364 return currentOffset;
3365 }
3366
3367 /**
3368 * Reads a JVMS 'verification_type_info' structure and stores it at the given index in the given
3369 * array.
3370 *
3371 * @param verificationTypeInfoOffset the start offset of the 'verification_type_info' structure to
3372 * read.
3373 * @param frame the array where the parsed type must be stored.
3374 * @param index the index in 'frame' where the parsed type must be stored.
3375 * @param charBuffer the buffer used to read strings in the constant pool.
3376 * @param labels the labels of the method currently being parsed, indexed by their offset. If the
3377 * parsed type is an ITEM_Uninitialized, a new label for the corresponding NEW instruction is
3378 * stored in this array if it does not already exist.
3379 * @return the end offset of the JVMS 'verification_type_info' structure.
3380 */
3381 private int readVerificationTypeInfo(
3382 final int verificationTypeInfoOffset,
3383 final Object[] frame,
3384 final int index,
3385 final char[] charBuffer,
3386 final Label[] labels) {
3387 int currentOffset = verificationTypeInfoOffset;
3388 int tag = classFileBuffer[currentOffset++] & 0xFF;
3389 switch (tag) {
3390 case Frame.ITEM_TOP:
3391 frame[index] = Opcodes.TOP;
3392 break;
3393 case Frame.ITEM_INTEGER:
3394 frame[index] = Opcodes.INTEGER;
3395 break;
3396 case Frame.ITEM_FLOAT:
3397 frame[index] = Opcodes.FLOAT;
3398 break;
3399 case Frame.ITEM_DOUBLE:
3400 frame[index] = Opcodes.DOUBLE;
3401 break;
3402 case Frame.ITEM_LONG:
3403 frame[index] = Opcodes.LONG;
3404 break;
3405 case Frame.ITEM_NULL:
3406 frame[index] = Opcodes.NULL;
3407 break;
3408 case Frame.ITEM_UNINITIALIZED_THIS:
3409 frame[index] = Opcodes.UNINITIALIZED_THIS;
3410 break;
3411 case Frame.ITEM_OBJECT:
3412 frame[index] = readClass(currentOffset, charBuffer);
3413 currentOffset += 2;
3414 break;
3415 case Frame.ITEM_UNINITIALIZED:
3416 frame[index] = createLabel(readUnsignedShort(currentOffset), labels);
3417 currentOffset += 2;
3418 break;
3419 default:
3420 throw new IllegalArgumentException();
3421 }
3422 return currentOffset;
3423 }
3424
3425 // ----------------------------------------------------------------------------------------------
3426 // Methods to parse attributes
3427 // ----------------------------------------------------------------------------------------------
3428
3429 /**
3430 * Returns the offset in {@link #classFileBuffer} of the first ClassFile's 'attributes' array
3431 * field entry.
3432 *
3433 * @return the offset in {@link #classFileBuffer} of the first ClassFile's 'attributes' array
3434 * field entry.
3435 */
3436 final int getFirstAttributeOffset() {
3437 // Skip the access_flags, this_class, super_class, and interfaces_count fields (using 2 bytes
3438 // each), as well as the interfaces array field (2 bytes per interface).
3439 int currentOffset = header + 8 + readUnsignedShort(header + 6) * 2;
3440
3441 // Read the fields_count field.
3442 int fieldsCount = readUnsignedShort(currentOffset);
3443 currentOffset += 2;
3444 // Skip the 'fields' array field.
3445 while (fieldsCount-- > 0) {
3446 // Invariant: currentOffset is the offset of a field_info structure.
3447 // Skip the access_flags, name_index and descriptor_index fields (2 bytes each), and read the
3448 // attributes_count field.
3449 int attributesCount = readUnsignedShort(currentOffset + 6);
3450 currentOffset += 8;
3451 // Skip the 'attributes' array field.
3452 while (attributesCount-- > 0) {
3453 // Invariant: currentOffset is the offset of an attribute_info structure.
3454 // Read the attribute_length field (2 bytes after the start of the attribute_info) and skip
3455 // this many bytes, plus 6 for the attribute_name_index and attribute_length fields
3456 // (yielding the total size of the attribute_info structure).
3457 currentOffset += 6 + readInt(currentOffset + 2);
3458 }
3459 }
3460
3461 // Skip the methods_count and 'methods' fields, using the same method as above.
3462 int methodsCount = readUnsignedShort(currentOffset);
3463 currentOffset += 2;
3464 while (methodsCount-- > 0) {
3465 int attributesCount = readUnsignedShort(currentOffset + 6);
3466 currentOffset += 8;
3467 while (attributesCount-- > 0) {
3468 currentOffset += 6 + readInt(currentOffset + 2);
3469 }
3470 }
3471
3472 // Skip the ClassFile's attributes_count field.
3473 return currentOffset + 2;
3474 }
3475
3476 /**
3477 * Reads the BootstrapMethods attribute to compute the offset of each bootstrap method.
3478 *
3479 * @param maxStringLength a conservative estimate of the maximum length of the strings contained
3480 * in the constant pool of the class.
3481 * @return the offsets of the bootstrap methods.
3482 */
3483 private int[] readBootstrapMethodsAttribute(final int maxStringLength) {
3484 char[] charBuffer = new char[maxStringLength];
3485 int currentAttributeOffset = getFirstAttributeOffset();
3486 int[] currentBootstrapMethodOffsets = null;
3487 for (int i = readUnsignedShort(currentAttributeOffset - 2); i > 0; --i) {
3488 // Read the attribute_info's attribute_name and attribute_length fields.
3489 String attributeName = readUTF8(currentAttributeOffset, charBuffer);
3490 int attributeLength = readInt(currentAttributeOffset + 2);
3491 currentAttributeOffset += 6;
3492 if (Constants.BOOTSTRAP_METHODS.equals(attributeName)) {
3493 // Read the num_bootstrap_methods field and create an array of this size.
3494 currentBootstrapMethodOffsets = new int[readUnsignedShort(currentAttributeOffset)];
3495 // Compute and store the offset of each 'bootstrap_methods' array field entry.
3496 int currentBootstrapMethodOffset = currentAttributeOffset + 2;
3497 for (int j = 0; j < currentBootstrapMethodOffsets.length; ++j) {
3498 currentBootstrapMethodOffsets[j] = currentBootstrapMethodOffset;
3499 // Skip the bootstrap_method_ref and num_bootstrap_arguments fields (2 bytes each),
3500 // as well as the bootstrap_arguments array field (of size num_bootstrap_arguments * 2).
3501 currentBootstrapMethodOffset +=
3502 4 + readUnsignedShort(currentBootstrapMethodOffset + 2) * 2;
3503 }
3504 return currentBootstrapMethodOffsets;
3505 }
3506 currentAttributeOffset += attributeLength;
3507 }
3508 throw new IllegalArgumentException();
3509 }
3510
3511 /**
3512 * Reads a non standard JVMS 'attribute' structure in {@link #classFileBuffer}.
3513 *
3514 * @param attributePrototypes prototypes of the attributes that must be parsed during the visit of
3515 * the class. Any attribute whose type is not equal to the type of one the prototypes will not
3516 * be parsed: its byte array value will be passed unchanged to the ClassWriter.
3517 * @param type the type of the attribute.
3518 * @param offset the start offset of the JVMS 'attribute' structure in {@link #classFileBuffer}.
3519 * The 6 attribute header bytes (attribute_name_index and attribute_length) are not taken into
3520 * account here.
3521 * @param length the length of the attribute's content (excluding the 6 attribute header bytes).
3522 * @param charBuffer the buffer to be used to read strings in the constant pool.
3523 * @param codeAttributeOffset the start offset of the enclosing Code attribute in {@link
3524 * #classFileBuffer}, or -1 if the attribute to be read is not a code attribute. The 6
3525 * attribute header bytes (attribute_name_index and attribute_length) are not taken into
3526 * account here.
3527 * @param labels the labels of the method's code, or {@literal null} if the attribute to be read
3528 * is not a code attribute.
3529 * @return the attribute that has been read.
3530 */
3531 private Attribute readAttribute(
3532 final Attribute[] attributePrototypes,
3533 final String type,
3534 final int offset,
3535 final int length,
3536 final char[] charBuffer,
3537 final int codeAttributeOffset,
3538 final Label[] labels) {
3539 for (Attribute attributePrototype : attributePrototypes) {
3540 if (attributePrototype.type.equals(type)) {
3541 return attributePrototype.read(
3542 this, offset, length, charBuffer, codeAttributeOffset, labels);
3543 }
3544 }
3545 return new Attribute(type).read(this, offset, length, null, -1, null);
3546 }
3547
3548 // -----------------------------------------------------------------------------------------------
3549 // Utility methods: low level parsing
3550 // -----------------------------------------------------------------------------------------------
3551
3552 /**
3553 * Returns the number of entries in the class's constant pool table.
3554 *
3555 * @return the number of entries in the class's constant pool table.
3556 */
3557 public int getItemCount() {
3558 return cpInfoOffsets.length;
3559 }
3560
3561 /**
3562 * Returns the start offset in this {@link ClassReader} of a JVMS 'cp_info' structure (i.e. a
3563 * constant pool entry), plus one. <i>This method is intended for {@link Attribute} sub classes,
3564 * and is normally not needed by class generators or adapters.</i>
3565 *
3566 * @param constantPoolEntryIndex the index a constant pool entry in the class's constant pool
3567 * table.
3568 * @return the start offset in this {@link ClassReader} of the corresponding JVMS 'cp_info'
3569 * structure, plus one.
3570 */
3571 public int getItem(final int constantPoolEntryIndex) {
3572 return cpInfoOffsets[constantPoolEntryIndex];
3573 }
3574
3575 /**
3576 * Returns a conservative estimate of the maximum length of the strings contained in the class's
3577 * constant pool table.
3578 *
3579 * @return a conservative estimate of the maximum length of the strings contained in the class's
3580 * constant pool table.
3581 */
3582 public int getMaxStringLength() {
3583 return maxStringLength;
3584 }
3585
3586 /**
3587 * Reads a byte value in this {@link ClassReader}. <i>This method is intended for {@link
3588 * Attribute} sub classes, and is normally not needed by class generators or adapters.</i>
3589 *
3590 * @param offset the start offset of the value to be read in this {@link ClassReader}.
3591 * @return the read value.
3592 */
3593 public int readByte(final int offset) {
3594 return classFileBuffer[offset] & 0xFF;
3595 }
3596
3597 /**
3598 * Reads an unsigned short value in this {@link ClassReader}. <i>This method is intended for
3599 * {@link Attribute} sub classes, and is normally not needed by class generators or adapters.</i>
3600 *
3601 * @param offset the start index of the value to be read in this {@link ClassReader}.
3602 * @return the read value.
3603 */
3604 public int readUnsignedShort(final int offset) {
3605 byte[] classBuffer = classFileBuffer;
3606 return ((classBuffer[offset] & 0xFF) << 8) | (classBuffer[offset + 1] & 0xFF);
3607 }
3608
3609 /**
3610 * Reads a signed short value in this {@link ClassReader}. <i>This method is intended for {@link
3611 * Attribute} sub classes, and is normally not needed by class generators or adapters.</i>
3612 *
3613 * @param offset the start offset of the value to be read in this {@link ClassReader}.
3614 * @return the read value.
3615 */
3616 public short readShort(final int offset) {
3617 byte[] classBuffer = classFileBuffer;
3618 return (short) (((classBuffer[offset] & 0xFF) << 8) | (classBuffer[offset + 1] & 0xFF));
3619 }
3620
3621 /**
3622 * Reads a signed int value in this {@link ClassReader}. <i>This method is intended for {@link
3623 * Attribute} sub classes, and is normally not needed by class generators or adapters.</i>
3624 *
3625 * @param offset the start offset of the value to be read in this {@link ClassReader}.
3626 * @return the read value.
3627 */
3628 public int readInt(final int offset) {
3629 byte[] classBuffer = classFileBuffer;
3630 return ((classBuffer[offset] & 0xFF) << 24)
3631 | ((classBuffer[offset + 1] & 0xFF) << 16)
3632 | ((classBuffer[offset + 2] & 0xFF) << 8)
3633 | (classBuffer[offset + 3] & 0xFF);
3634 }
3635
3636 /**
3637 * Reads a signed long value in this {@link ClassReader}. <i>This method is intended for {@link
3638 * Attribute} sub classes, and is normally not needed by class generators or adapters.</i>
3639 *
3640 * @param offset the start offset of the value to be read in this {@link ClassReader}.
3641 * @return the read value.
3642 */
3643 public long readLong(final int offset) {
3644 long l1 = readInt(offset);
3645 long l0 = readInt(offset + 4) & 0xFFFFFFFFL;
3646 return (l1 << 32) | l0;
3647 }
3648
3649 /**
3650 * Reads a CONSTANT_Utf8 constant pool entry in this {@link ClassReader}. <i>This method is
3651 * intended for {@link Attribute} sub classes, and is normally not needed by class generators or
3652 * adapters.</i>
3653 *
3654 * @param offset the start offset of an unsigned short value in this {@link ClassReader}, whose
3655 * value is the index of a CONSTANT_Utf8 entry in the class's constant pool table.
3656 * @param charBuffer the buffer to be used to read the string. This buffer must be sufficiently
3657 * large. It is not automatically resized.
3658 * @return the String corresponding to the specified CONSTANT_Utf8 entry.
3659 */
3660 // DontCheck(AbbreviationAsWordInName): can't be renamed (for backward binary compatibility).
3661 public String readUTF8(final int offset, final char[] charBuffer) {
3662 int constantPoolEntryIndex = readUnsignedShort(offset);
3663 if (offset == 0 || constantPoolEntryIndex == 0) {
3664 return null;
3665 }
3666 return readUtf(constantPoolEntryIndex, charBuffer);
3667 }
3668
3669 /**
3670 * Reads a CONSTANT_Utf8 constant pool entry in {@link #classFileBuffer}.
3671 *
3672 * @param constantPoolEntryIndex the index of a CONSTANT_Utf8 entry in the class's constant pool
3673 * table.
3674 * @param charBuffer the buffer to be used to read the string. This buffer must be sufficiently
3675 * large. It is not automatically resized.
3676 * @return the String corresponding to the specified CONSTANT_Utf8 entry.
3677 */
3678 final String readUtf(final int constantPoolEntryIndex, final char[] charBuffer) {
3679 String value = constantUtf8Values[constantPoolEntryIndex];
3680 if (value != null) {
3681 return value;
3682 }
3683 int cpInfoOffset = cpInfoOffsets[constantPoolEntryIndex];
3684 return constantUtf8Values[constantPoolEntryIndex] =
3685 readUtf(cpInfoOffset + 2, readUnsignedShort(cpInfoOffset), charBuffer);
3686 }
3687
3688 /**
3689 * Reads an UTF8 string in {@link #classFileBuffer}.
3690 *
3691 * @param utfOffset the start offset of the UTF8 string to be read.
3692 * @param utfLength the length of the UTF8 string to be read.
3693 * @param charBuffer the buffer to be used to read the string. This buffer must be sufficiently
3694 * large. It is not automatically resized.
3695 * @return the String corresponding to the specified UTF8 string.
3696 */
3697 private String readUtf(final int utfOffset, final int utfLength, final char[] charBuffer) {
3698 int currentOffset = utfOffset;
3699 int endOffset = currentOffset + utfLength;
3700 int strLength = 0;
3701 byte[] classBuffer = classFileBuffer;
3702 while (currentOffset < endOffset) {
3703 int currentByte = classBuffer[currentOffset++];
3704 if ((currentByte & 0x80) == 0) {
3705 charBuffer[strLength++] = (char) (currentByte & 0x7F);
3706 } else if ((currentByte & 0xE0) == 0xC0) {
3707 charBuffer[strLength++] =
3708 (char) (((currentByte & 0x1F) << 6) + (classBuffer[currentOffset++] & 0x3F));
3709 } else {
3710 charBuffer[strLength++] =
3711 (char)
3712 (((currentByte & 0xF) << 12)
3713 + ((classBuffer[currentOffset++] & 0x3F) << 6)
3714 + (classBuffer[currentOffset++] & 0x3F));
3715 }
3716 }
3717 return new String(charBuffer, 0, strLength);
3718 }
3719
3720 /**
3721 * Reads a CONSTANT_Class, CONSTANT_String, CONSTANT_MethodType, CONSTANT_Module or
3722 * CONSTANT_Package constant pool entry in {@link #classFileBuffer}. <i>This method is intended
3723 * for {@link Attribute} sub classes, and is normally not needed by class generators or
3724 * adapters.</i>
3725 *
3726 * @param offset the start offset of an unsigned short value in {@link #classFileBuffer}, whose
3727 * value is the index of a CONSTANT_Class, CONSTANT_String, CONSTANT_MethodType,
3728 * CONSTANT_Module or CONSTANT_Package entry in class's constant pool table.
3729 * @param charBuffer the buffer to be used to read the item. This buffer must be sufficiently
3730 * large. It is not automatically resized.
3731 * @return the String corresponding to the specified constant pool entry.
3732 */
3733 private String readStringish(final int offset, final char[] charBuffer) {
3734 // Get the start offset of the cp_info structure (plus one), and read the CONSTANT_Utf8 entry
3735 // designated by the first two bytes of this cp_info.
3736 return readUTF8(cpInfoOffsets[readUnsignedShort(offset)], charBuffer);
3737 }
3738
3739 /**
3740 * Reads a CONSTANT_Class constant pool entry in this {@link ClassReader}. <i>This method is
3741 * intended for {@link Attribute} sub classes, and is normally not needed by class generators or
3742 * adapters.</i>
3743 *
3744 * @param offset the start offset of an unsigned short value in this {@link ClassReader}, whose
3745 * value is the index of a CONSTANT_Class entry in class's constant pool table.
3746 * @param charBuffer the buffer to be used to read the item. This buffer must be sufficiently
3747 * large. It is not automatically resized.
3748 * @return the String corresponding to the specified CONSTANT_Class entry.
3749 */
3750 public String readClass(final int offset, final char[] charBuffer) {
3751 return readStringish(offset, charBuffer);
3752 }
3753
3754 /**
3755 * Reads a CONSTANT_Module constant pool entry in this {@link ClassReader}. <i>This method is
3756 * intended for {@link Attribute} sub classes, and is normally not needed by class generators or
3757 * adapters.</i>
3758 *
3759 * @param offset the start offset of an unsigned short value in this {@link ClassReader}, whose
3760 * value is the index of a CONSTANT_Module entry in class's constant pool table.
3761 * @param charBuffer the buffer to be used to read the item. This buffer must be sufficiently
3762 * large. It is not automatically resized.
3763 * @return the String corresponding to the specified CONSTANT_Module entry.
3764 */
3765 public String readModule(final int offset, final char[] charBuffer) {
3766 return readStringish(offset, charBuffer);
3767 }
3768
3769 /**
3770 * Reads a CONSTANT_Package constant pool entry in this {@link ClassReader}. <i>This method is
3771 * intended for {@link Attribute} sub classes, and is normally not needed by class generators or
3772 * adapters.</i>
3773 *
3774 * @param offset the start offset of an unsigned short value in this {@link ClassReader}, whose
3775 * value is the index of a CONSTANT_Package entry in class's constant pool table.
3776 * @param charBuffer the buffer to be used to read the item. This buffer must be sufficiently
3777 * large. It is not automatically resized.
3778 * @return the String corresponding to the specified CONSTANT_Package entry.
3779 */
3780 public String readPackage(final int offset, final char[] charBuffer) {
3781 return readStringish(offset, charBuffer);
3782 }
3783
3784 /**
3785 * Reads a CONSTANT_Dynamic constant pool entry in {@link #classFileBuffer}.
3786 *
3787 * @param constantPoolEntryIndex the index of a CONSTANT_Dynamic entry in the class's constant
3788 * pool table.
3789 * @param charBuffer the buffer to be used to read the string. This buffer must be sufficiently
3790 * large. It is not automatically resized.
3791 * @return the ConstantDynamic corresponding to the specified CONSTANT_Dynamic entry.
3792 */
3793 private ConstantDynamic readConstantDynamic(
3794 final int constantPoolEntryIndex, final char[] charBuffer) {
3795 ConstantDynamic constantDynamic = constantDynamicValues[constantPoolEntryIndex];
3796 if (constantDynamic != null) {
3797 return constantDynamic;
3798 }
3799 int cpInfoOffset = cpInfoOffsets[constantPoolEntryIndex];
3800 int nameAndTypeCpInfoOffset = cpInfoOffsets[readUnsignedShort(cpInfoOffset + 2)];
3801 String name = readUTF8(nameAndTypeCpInfoOffset, charBuffer);
3802 String descriptor = readUTF8(nameAndTypeCpInfoOffset + 2, charBuffer);
3803 int bootstrapMethodOffset = bootstrapMethodOffsets[readUnsignedShort(cpInfoOffset)];
3804 Handle handle = (Handle) readConst(readUnsignedShort(bootstrapMethodOffset), charBuffer);
3805 Object[] bootstrapMethodArguments = new Object[readUnsignedShort(bootstrapMethodOffset + 2)];
3806 bootstrapMethodOffset += 4;
3807 for (int i = 0; i < bootstrapMethodArguments.length; i++) {
3808 bootstrapMethodArguments[i] = readConst(readUnsignedShort(bootstrapMethodOffset), charBuffer);
3809 bootstrapMethodOffset += 2;
3810 }
3811 return constantDynamicValues[constantPoolEntryIndex] =
3812 new ConstantDynamic(name, descriptor, handle, bootstrapMethodArguments);
3813 }
3814
3815 /**
3816 * Reads a numeric or string constant pool entry in this {@link ClassReader}. <i>This method is
3817 * intended for {@link Attribute} sub classes, and is normally not needed by class generators or
3818 * adapters.</i>
3819 *
3820 * @param constantPoolEntryIndex the index of a CONSTANT_Integer, CONSTANT_Float, CONSTANT_Long,
3821 * CONSTANT_Double, CONSTANT_Class, CONSTANT_String, CONSTANT_MethodType,
3822 * CONSTANT_MethodHandle or CONSTANT_Dynamic entry in the class's constant pool.
3823 * @param charBuffer the buffer to be used to read strings. This buffer must be sufficiently
3824 * large. It is not automatically resized.
3825 * @return the {@link Integer}, {@link Float}, {@link Long}, {@link Double}, {@link String},
3826 * {@link Type}, {@link Handle} or {@link ConstantDynamic} corresponding to the specified
3827 * constant pool entry.
3828 */
3829 public Object readConst(final int constantPoolEntryIndex, final char[] charBuffer) {
3830 int cpInfoOffset = cpInfoOffsets[constantPoolEntryIndex];
3831 switch (classFileBuffer[cpInfoOffset - 1]) {
3832 case Symbol.CONSTANT_INTEGER_TAG:
3833 return readInt(cpInfoOffset);
3834 case Symbol.CONSTANT_FLOAT_TAG:
3835 return Float.intBitsToFloat(readInt(cpInfoOffset));
3836 case Symbol.CONSTANT_LONG_TAG:
3837 return readLong(cpInfoOffset);
3838 case Symbol.CONSTANT_DOUBLE_TAG:
3839 return Double.longBitsToDouble(readLong(cpInfoOffset));
3840 case Symbol.CONSTANT_CLASS_TAG:
3841 return Type.getObjectType(readUTF8(cpInfoOffset, charBuffer));
3842 case Symbol.CONSTANT_STRING_TAG:
3843 return readUTF8(cpInfoOffset, charBuffer);
3844 case Symbol.CONSTANT_METHOD_TYPE_TAG:
3845 return Type.getMethodType(readUTF8(cpInfoOffset, charBuffer));
3846 case Symbol.CONSTANT_METHOD_HANDLE_TAG:
3847 int referenceKind = readByte(cpInfoOffset);
3848 int referenceCpInfoOffset = cpInfoOffsets[readUnsignedShort(cpInfoOffset + 1)];
3849 int nameAndTypeCpInfoOffset = cpInfoOffsets[readUnsignedShort(referenceCpInfoOffset + 2)];
3850 String owner = readClass(referenceCpInfoOffset, charBuffer);
3851 String name = readUTF8(nameAndTypeCpInfoOffset, charBuffer);
3852 String descriptor = readUTF8(nameAndTypeCpInfoOffset + 2, charBuffer);
3853 boolean isInterface =
3854 classFileBuffer[referenceCpInfoOffset - 1] == Symbol.CONSTANT_INTERFACE_METHODREF_TAG;
3855 return new Handle(referenceKind, owner, name, descriptor, isInterface);
3856 case Symbol.CONSTANT_DYNAMIC_TAG:
3857 return readConstantDynamic(constantPoolEntryIndex, charBuffer);
3858 default:
3859 throw new IllegalArgumentException();
3860 }
3861 }
3862 }