1 /*
2 * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.internal.access;
27
28 import java.io.InputStream;
29 import java.io.PrintStream;
30 import java.lang.annotation.Annotation;
31 import java.lang.foreign.MemorySegment;
32 import java.lang.foreign.SymbolLookup;
33 import java.lang.invoke.MethodHandle;
34 import java.lang.invoke.MethodType;
35 import java.lang.module.ModuleDescriptor;
36 import java.lang.reflect.ClassFileFormatVersion;
37 import java.lang.reflect.Executable;
38 import java.lang.reflect.Method;
39 import java.net.URI;
40 import java.nio.charset.CharacterCodingException;
41 import java.nio.charset.Charset;
42 import java.security.ProtectionDomain;
43 import java.util.List;
44 import java.util.Map;
45 import java.util.Set;
46 import java.util.concurrent.ConcurrentHashMap;
47 import java.util.concurrent.Executor;
48 import java.util.concurrent.RejectedExecutionException;
49 import java.util.function.BiFunction;
50 import java.util.stream.Stream;
51
52 import jdk.internal.loader.NativeLibraries;
53 import jdk.internal.misc.CarrierThreadLocal;
54 import jdk.internal.module.ServicesCatalog;
55 import jdk.internal.reflect.ConstantPool;
56 import jdk.internal.vm.Continuation;
57 import jdk.internal.vm.ContinuationScope;
58 import jdk.internal.vm.StackableScope;
59 import jdk.internal.vm.ThreadContainer;
60 import sun.reflect.annotation.AnnotationType;
61 import sun.nio.ch.Interruptible;
62
63 public interface JavaLangAccess {
64
65 /**
66 * Returns the list of {@code Method} objects for the declared public
67 * methods of this class or interface that have the specified method name
68 * and parameter types.
69 */
70 List<Method> getDeclaredPublicMethods(Class<?> klass, String name, Class<?>... parameterTypes);
71
72 /**
73 * Return most specific method that matches name and parameterTypes.
74 */
75 Method findMethod(Class<?> klass, boolean publicOnly, String name, Class<?>... parameterTypes);
76
77 /**
78 * Return the constant pool for a class.
79 */
80 ConstantPool getConstantPool(Class<?> klass);
81
82 /**
83 * Compare-And-Set the AnnotationType instance corresponding to this class.
84 * (This method only applies to annotation types.)
85 */
86 boolean casAnnotationType(Class<?> klass, AnnotationType oldType, AnnotationType newType);
87
88 /**
89 * Get the AnnotationType instance corresponding to this class.
90 * (This method only applies to annotation types.)
91 */
92 AnnotationType getAnnotationType(Class<?> klass);
93
94 /**
95 * Get the declared annotations for a given class, indexed by their types.
96 */
97 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap(Class<?> klass);
98
99 /**
100 * Get the array of bytes that is the class-file representation
101 * of this Class' annotations.
102 */
103 byte[] getRawClassAnnotations(Class<?> klass);
104
105 /**
106 * Get the array of bytes that is the class-file representation
107 * of this Class' type annotations.
108 */
109 byte[] getRawClassTypeAnnotations(Class<?> klass);
110
111 /**
112 * Get the array of bytes that is the class-file representation
113 * of this Executable's type annotations.
114 */
115 byte[] getRawExecutableTypeAnnotations(Executable executable);
116
117 /**
118 * Get the int value of the Class's class-file access flags.
119 */
120 int getClassFileAccessFlags(Class<?> klass);
121
122 /**
123 * Returns the elements of an enum class or null if the
124 * Class object does not represent an enum type;
125 * the result is uncloned, cached, and shared by all callers.
126 */
127 <E extends Enum<E>> E[] getEnumConstantsShared(Class<E> klass);
128
129 /**
130 * Returns the big-endian packed minor-major version of the class file
131 * of this class.
132 */
133 int classFileVersion(Class<?> clazz);
134
135 /**
136 * Set current thread's blocker field.
137 */
138 void blockedOn(Interruptible b);
139
140 /**
141 * Registers a shutdown hook.
142 *
143 * It is expected that this method with registerShutdownInProgress=true
144 * is only used to register DeleteOnExitHook since the first file
145 * may be added to the delete on exit list by the application shutdown
146 * hooks.
147 *
148 * @param slot the slot in the shutdown hook array, whose element
149 * will be invoked in order during shutdown
150 * @param registerShutdownInProgress true to allow the hook
151 * to be registered even if the shutdown is in progress.
152 * @param hook the hook to be registered
153 *
154 * @throws IllegalStateException if shutdown is in progress and
155 * the slot is not valid to register.
156 */
157 void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook);
158
159 /**
160 * Invokes the finalize method of the given object.
161 */
162 void invokeFinalize(Object o) throws Throwable;
163
164 /**
165 * Returns the ConcurrentHashMap used as a storage for ClassLoaderValue(s)
166 * associated with the given class loader, creating it if it doesn't already exist.
167 */
168 ConcurrentHashMap<?, ?> createOrGetClassLoaderValueMap(ClassLoader cl);
169
170 /**
171 * Defines a class with the given name to a class loader.
172 */
173 Class<?> defineClass(ClassLoader cl, String name, byte[] b, ProtectionDomain pd, String source);
174
175 /**
176 * Defines a class with the given name to a class loader with
177 * the given flags and class data.
178 *
179 * @see java.lang.invoke.MethodHandles.Lookup#defineClass
180 */
181 Class<?> defineClass(ClassLoader cl, Class<?> lookup, String name, byte[] b, ProtectionDomain pd, boolean initialize, int flags, Object classData);
182
183 /**
184 * Returns a class loaded by the bootstrap class loader.
185 */
186 Class<?> findBootstrapClassOrNull(String name);
187
188 /**
189 * Define a Package of the given name and module by the given class loader.
190 */
191 Package definePackage(ClassLoader cl, String name, Module module);
192
193 /**
194 * Defines a new module to the Java virtual machine. The module
195 * is defined to the given class loader.
196 *
197 * The URI is for information purposes only, it can be {@code null}.
198 */
199 Module defineModule(ClassLoader loader, ModuleDescriptor descriptor, URI uri);
200
201 /**
202 * Defines the unnamed module for the given class loader.
203 */
204 Module defineUnnamedModule(ClassLoader loader);
205
206 /**
207 * Updates the readability so that module m1 reads m2. The new read edge
208 * does not result in a strong reference to m2 (m2 can be GC'ed).
209 *
210 * This method is the same as m1.addReads(m2) but without a permission check.
211 */
212 void addReads(Module m1, Module m2);
213
214 /**
215 * Updates module m to read all unnamed modules.
216 */
217 void addReadsAllUnnamed(Module m);
218
219 /**
220 * Updates module m1 to export a package unconditionally.
221 */
222 void addExports(Module m1, String pkg);
223
224 /**
225 * Updates module m1 to export a package to module m2. The export does
226 * not result in a strong reference to m2 (m2 can be GC'ed).
227 */
228 void addExports(Module m1, String pkg, Module m2);
229
230 /**
231 * Updates a module m to export a package to all unnamed modules.
232 */
233 void addExportsToAllUnnamed(Module m, String pkg);
234
235 /**
236 * Updates module m1 to open a package to module m2. Opening the
237 * package does not result in a strong reference to m2 (m2 can be GC'ed).
238 */
239 void addOpens(Module m1, String pkg, Module m2);
240
241 /**
242 * Updates module m to open a package to all unnamed modules.
243 */
244 void addOpensToAllUnnamed(Module m, String pkg);
245
246 /**
247 * Updates module m to use a service.
248 */
249 void addUses(Module m, Class<?> service);
250
251 /**
252 * Returns true if module m reflectively exports a package to other
253 */
254 boolean isReflectivelyExported(Module module, String pn, Module other);
255
256 /**
257 * Returns true if module m reflectively opens a package to other
258 */
259 boolean isReflectivelyOpened(Module module, String pn, Module other);
260
261 /**
262 * Updates module m to allow access to restricted methods.
263 */
264 Module addEnableNativeAccess(Module m);
265
266 /**
267 * Updates module named {@code name} in layer {@code layer} to allow access to restricted methods.
268 * Returns true iff the given module exists in the given layer.
269 */
270 boolean addEnableNativeAccess(ModuleLayer layer, String name);
271
272 /**
273 * Updates all unnamed modules to allow access to restricted methods.
274 */
275 void addEnableNativeAccessToAllUnnamed();
276
277 /**
278 * Ensure that the given module has native access. If not, warn or throw exception depending on the configuration.
279 * @param m the module in which native access occurred
280 * @param owner the owner of the restricted method being called (or the JNI method being bound)
281 * @param methodName the name of the restricted method being called (or the JNI method being bound)
282 * @param currentClass the class calling the restricted method (for JNI, this is the same as {@code owner})
283 * @param jni {@code true}, if this event is related to a JNI method being bound
284 */
285 void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass, boolean jni);
286
287 /**
288 * Returns the ServicesCatalog for the given Layer.
289 */
290 ServicesCatalog getServicesCatalog(ModuleLayer layer);
291
292 /**
293 * Record that this layer has at least one module defined to the given
294 * class loader.
295 */
296 void bindToLoader(ModuleLayer layer, ClassLoader loader);
297
298 /**
299 * Returns an ordered stream of layers. The first element is the
300 * given layer, the remaining elements are its parents, in DFS order.
301 */
302 Stream<ModuleLayer> layers(ModuleLayer layer);
303
304 /**
305 * Returns a stream of the layers that have modules defined to the
306 * given class loader.
307 */
308 Stream<ModuleLayer> layers(ClassLoader loader);
309
310 /**
311 * Count the number of leading positive bytes in the range.
312 *
313 * @implSpec Implementations of this method must perform bounds checks.
314 */
315 int countPositives(byte[] ba, int off, int len);
316
317 /**
318 * Count the number of leading non-zero ascii chars in the String.
319 */
320 int countNonZeroAscii(String s);
321
322 /**
323 * Constructs a new {@code String} with the supplied Latin1 bytes.
324 * <p>
325 * <b>WARNING: The caller of this method shall relinquish and transfer the
326 * ownership of the byte array to the callee</b>, since the latter will not
327 * make a copy.
328 *
329 * @param bytes the byte array source
330 * @return the newly created string
331 */
332 String uncheckedNewStringWithLatin1Bytes(byte[] bytes);
333
334 /**
335 * Constructs a new {@code String} by decoding the specified byte array
336 * using the specified {@linkplain java.nio.charset.Charset charset}.
337 * <p>
338 * <b>WARNING: The caller of this method shall relinquish and transfer the
339 * ownership of the byte array to the callee</b>, since the latter will not
340 * make a copy.
341 *
342 * @param bytes the byte array source
343 * @param cs the Charset
344 * @return the newly created string
345 * @throws CharacterCodingException for malformed or unmappable bytes
346 */
347 String uncheckedNewStringNoRepl(byte[] bytes, Charset cs) throws CharacterCodingException;
348
349 /**
350 * Encode the given string into a sequence of bytes using the specified
351 * {@linkplain java.nio.charset.Charset charset}.
352 * <p>
353 * <b>WARNING: This method returns the {@code byte[]} backing the provided
354 * {@code String}, if the input is ASCII. Hence, the returned byte array
355 * must not be modified.</b>
356 * <p>
357 * This method throws {@code CharacterCodingException} instead of replacing
358 * when malformed input or unmappable characters are encountered.
359 *
360 * @param s the string to encode
361 * @param cs the charset
362 * @return the encoded bytes
363 * @throws CharacterCodingException for malformed input or unmappable characters
364 */
365 byte[] uncheckedGetBytesNoRepl(String s, Charset cs) throws CharacterCodingException;
366
367 /**
368 * Get the {@code char} at {@code index} in a {@code byte[]} in internal
369 * UTF-16 representation.
370 * <p>
371 * <b>WARNING: This method does not perform any bound checks.</b>
372 *
373 * @param bytes the UTF-16 encoded bytes
374 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
375 * @return the char value
376 */
377 char uncheckedGetUTF16Char(byte[] bytes, int index);
378
379 /**
380 * Put the {@code ch} at {@code index} in a {@code byte[]} in internal
381 * UTF-16 representation.
382 * <p>
383 * <b>WARNING: This method does not perform any bound checks.</b>
384 *
385 * @param bytes the UTF-16 encoded bytes
386 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
387 */
388 void uncheckedPutCharUTF16(byte[] bytes, int index, int ch);
389
390 /**
391 * Encode the given string into a sequence of bytes using utf8.
392 *
393 * @param s the string to encode
394 * @return the encoded bytes in utf8
395 * @throws IllegalArgumentException for malformed surrogates
396 */
397 byte[] getBytesUTF8NoRepl(String s);
398
399 /**
400 * Inflated copy from {@code byte[]} to {@code char[]}, as defined by
401 * {@code StringLatin1.inflate}.
402 *
403 * @implSpec Implementations of this method must perform bounds checks.
404 */
405 void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len);
406
407 /**
408 * Decodes ASCII from the source byte array into the destination
409 * char array.
410 *
411 * @implSpec Implementations of this method must perform bounds checks.
412 *
413 * @return the number of bytes successfully decoded, at most len
414 */
415 int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len);
416
417 /**
418 * Returns the initial `System.in` to determine if it is replaced
419 * with `System.setIn(newIn)` method
420 */
421 InputStream initialSystemIn();
422
423 /**
424 * Returns the initial value of System.err.
425 */
426 PrintStream initialSystemErr();
427
428 /**
429 * Encodes as many ASCII codepoints as possible from the source
430 * character array into the destination byte array, assuming that
431 * the encoding is ASCII compatible.
432 *
433 * @param sa the source character array
434 * @param sp the index of the source array to start reading from
435 * @param da the target byte array
436 * @param dp the index of the target array to start writing to
437 * @param len the total number of characters to be encoded
438 * @return the total number of characters successfully encoded
439 * @throws NullPointerException if any of the provided arrays is null
440 */
441 int encodeASCII(char[] sa, int sp, byte[] da, int dp, int len);
442
443 /**
444 * Set the cause of Throwable
445 * @param cause set t's cause to new value
446 */
447 void setCause(Throwable t, Throwable cause);
448
449 /**
450 * Get protection domain of the given Class
451 */
452 ProtectionDomain protectionDomain(Class<?> c);
453
454 /**
455 * Get a method handle of string concat helper method
456 */
457 MethodHandle stringConcatHelper(String name, MethodType methodType);
458
459 /**
460 * Get the string concat initial coder
461 */
462 long stringConcatInitialCoder();
463
464 /**
465 * Update lengthCoder for constant
466 */
467 long stringConcatMix(long lengthCoder, String constant);
468
469 /**
470 * Mix value length and coder into current length and coder.
471 */
472 long stringConcatMix(long lengthCoder, char value);
473
474 /**
475 * Creates helper for string concatenation.
476 * <p>
477 * <b>WARNING: The caller of this method shall relinquish and transfer the
478 * ownership of the string array to the callee</b>, since the latter will not
479 * make a copy.
480 */
481 Object uncheckedStringConcat1(String[] constants);
482
483 /**
484 * Get the string initial coder, When COMPACT_STRINGS is on, it returns 0, and when it is off, it returns 1.
485 */
486 byte stringInitCoder();
487
488 /**
489 * Get the Coder of String, which is used by StringConcatFactory to calculate the initCoder of constants
490 */
491 byte stringCoder(String str);
492
493 /**
494 * Join strings
495 */
496 String join(String prefix, String suffix, String delimiter, String[] elements, int size);
497
498 /**
499 * Concatenation of prefix and suffix characters to a String for early bootstrap
500 */
501 String concat(String prefix, Object value, String suffix);
502
503 /*
504 * Get the class data associated with the given class.
505 * @param c the class
506 * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
507 */
508 Object classData(Class<?> c);
509
510 /**
511 * Returns the {@link NativeLibraries} object associated with the provided class loader.
512 * This is used by {@link SymbolLookup#loaderLookup()}.
513 */
514 NativeLibraries nativeLibrariesFor(ClassLoader loader);
515
516 /**
517 * Returns an array of all platform threads.
518 */
519 Thread[] getAllThreads();
520
521 /**
522 * Returns the ThreadContainer for a thread, may be null.
523 */
524 ThreadContainer threadContainer(Thread thread);
525
526 /**
527 * Starts a thread in the given ThreadContainer.
528 */
529 void start(Thread thread, ThreadContainer container);
530
531 /**
532 * Returns the top of the given thread's stackable scope stack.
533 */
534 StackableScope headStackableScope(Thread thread);
535
536 /**
537 * Sets the top of the current thread's stackable scope stack.
538 */
539 void setHeadStackableScope(StackableScope scope);
540
541 /**
542 * Returns the Thread object for the current platform thread. If the
543 * current thread is a virtual thread then this method returns the carrier.
544 */
545 Thread currentCarrierThread();
546
547 /**
548 * Returns the value of the current carrier thread's copy of a thread-local.
549 */
550 <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local);
551
552 /**
553 * Sets the value of the current carrier thread's copy of a thread-local.
554 */
555 <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value);
556
557 /**
558 * Removes the value of the current carrier thread's copy of a thread-local.
559 */
560 void removeCarrierThreadLocal(CarrierThreadLocal<?> local);
561
562 /**
563 * Returns the current thread's scoped values cache
564 */
565 Object[] scopedValueCache();
566
567 /**
568 * Sets the current thread's scoped values cache
569 */
570 void setScopedValueCache(Object[] cache);
571
572 /**
573 * Return the current thread's scoped value bindings.
574 */
575 Object scopedValueBindings();
576
577 /**
578 * Returns the innermost mounted continuation
579 */
580 Continuation getContinuation(Thread thread);
581
582 /**
583 * Sets the innermost mounted continuation
584 */
585 void setContinuation(Thread thread, Continuation continuation);
586
587 /**
588 * The ContinuationScope of virtual thread continuations
589 */
590 ContinuationScope virtualThreadContinuationScope();
591
592 /**
593 * Parks the current virtual thread.
594 * @throws WrongThreadException if the current thread is not a virtual thread
595 */
596 void parkVirtualThread();
597
598 /**
599 * Parks the current virtual thread for up to the given waiting time.
600 * @param nanos the maximum number of nanoseconds to wait
601 * @throws WrongThreadException if the current thread is not a virtual thread
602 */
603 void parkVirtualThread(long nanos);
604
605 /**
606 * Re-enables a virtual thread for scheduling. If the thread was parked then
607 * it will be unblocked, otherwise its next attempt to park will not block
608 * @param thread the virtual thread to unpark
609 * @throws IllegalArgumentException if the thread is not a virtual thread
610 * @throws RejectedExecutionException if the scheduler cannot accept a task
611 */
612 void unparkVirtualThread(Thread thread);
613
614 /**
615 * Returns the virtual thread default scheduler.
616 */
617 Executor virtualThreadDefaultScheduler();
618
619 /**
620 * Creates a new StackWalker
621 */
622 StackWalker newStackWalkerInstance(Set<StackWalker.Option> options,
623 ContinuationScope contScope,
624 Continuation continuation);
625
626 /**
627 * Returns the class file format version of the class.
628 */
629 int classFileFormatVersion(Class<?> klass);
630
631 /**
632 * Returns '<loader-name>' @<id> if classloader has a name
633 * explicitly set otherwise <qualified-class-name> @<id>
634 */
635 String getLoaderNameID(ClassLoader loader);
636
637 /**
638 * Copy the string bytes to an existing segment, avoiding intermediate copies.
639 */
640 void copyToSegmentRaw(String string, MemorySegment segment, long offset);
641
642 /**
643 * Are the string bytes compatible with the given charset?
644 */
645 boolean bytesCompatible(String string, Charset charset);
646 }