1 /*
2 * Copyright (c) 1996, 2024, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2024, Alibaba Group Holding Limited. All Rights Reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation. Oracle designates this
9 * particular file as subject to the "Classpath" exception as provided
10 * by Oracle in the LICENSE file that accompanied this code.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23 * or visit www.oracle.com if you need additional information or have any
24 * questions.
25 */
26
27 package java.io;
28
29 import java.security.AccessController;
30 import java.security.PrivilegedAction;
31 import java.util.ArrayList;
32 import java.util.Arrays;
33 import java.util.List;
34 import java.util.Objects;
35 import java.util.StringJoiner;
36
37 import jdk.internal.util.ByteArray;
38 import jdk.internal.access.JavaLangAccess;
39 import jdk.internal.access.SharedSecrets;
40 import sun.reflect.misc.ReflectUtil;
41
42 import static jdk.internal.util.ModifiedUtf.putChar;
43 import static jdk.internal.util.ModifiedUtf.utfLen;
44
45 /**
46 * An ObjectOutputStream writes primitive data types and graphs of Java objects
47 * to an OutputStream. The objects can be read (reconstituted) using an
48 * ObjectInputStream. Persistent storage of objects can be accomplished by
49 * using a file for the stream. If the stream is a network socket stream, the
50 * objects can be reconstituted on another host or in another process.
51 *
52 * <p>Only objects that support the java.io.Serializable interface can be
53 * written to streams. The class of each serializable object is encoded
54 * including the class name and signature of the class, the values of the
55 * object's fields and arrays, and the closure of any other objects referenced
56 * from the initial objects.
57 *
58 * <p>The method writeObject is used to write an object to the stream. Any
59 * object, including Strings and arrays, is written with writeObject. Multiple
60 * objects or primitives can be written to the stream. The objects must be
61 * read back from the corresponding ObjectInputstream with the same types and
62 * in the same order as they were written.
63 *
64 * <p>Primitive data types can also be written to the stream using the
65 * appropriate methods from DataOutput. Strings can also be written using the
66 * writeUTF method.
67 *
68 * <p>The default serialization mechanism for an object writes the class of the
69 * object, the class signature, and the values of all non-transient and
70 * non-static fields. References to other objects (except in transient or
71 * static fields) cause those objects to be written also. Multiple references
72 * to a single object are encoded using a reference sharing mechanism so that
73 * graphs of objects can be restored to the same shape as when the original was
74 * written.
75 *
76 * <p>For example to write an object that can be read by the example in
77 * {@link ObjectInputStream}:
78 * {@snippet lang="java":
79 * try (FileOutputStream fos = new FileOutputStream("t.tmp");
80 * ObjectOutputStream oos = new ObjectOutputStream(fos)) {
81 * oos.writeObject("Today");
82 * oos.writeObject(LocalDateTime.now());
83 * } catch (Exception ex) {
84 * // handle exception
85 * }
86 * }
87 *
88 * <p>Serializable classes that require special handling during the
89 * serialization and deserialization process should implement methods
90 * with the following signatures:
91 *
92 * {@snippet lang="java":
93 * private void readObject(java.io.ObjectInputStream stream)
94 * throws IOException, ClassNotFoundException;
95 * private void writeObject(java.io.ObjectOutputStream stream)
96 * throws IOException;
97 * private void readObjectNoData()
98 * throws ObjectStreamException;
99 * }
100 *
101 * <p>The method name, modifiers, return type, and number and type of
102 * parameters must match exactly for the method to be used by
103 * serialization or deserialization. The methods should only be
104 * declared to throw checked exceptions consistent with these
105 * signatures.
106 *
107 * <p>The writeObject method is responsible for writing the state of the object
108 * for its particular class so that the corresponding readObject method can
109 * restore it. The method does not need to concern itself with the state
110 * belonging to the object's superclasses or subclasses. State is saved by
111 * writing the individual fields to the ObjectOutputStream using the
112 * writeObject method or by using the methods for primitive data types
113 * supported by DataOutput.
114 *
115 * <p>Serialization does not write out the fields of any object that does not
116 * implement the java.io.Serializable interface. Subclasses of Objects that
117 * are not serializable can be serializable. In this case the non-serializable
118 * class must have a no-arg constructor to allow its fields to be initialized.
119 * In this case it is the responsibility of the subclass to save and restore
120 * the state of the non-serializable class. It is frequently the case that the
121 * fields of that class are accessible (public, package, or protected) or that
122 * there are get and set methods that can be used to restore the state.
123 *
124 * <p>Serialization of an object can be prevented by implementing writeObject
125 * and readObject methods that throw the NotSerializableException. The
126 * exception will be caught by the ObjectOutputStream and abort the
127 * serialization process.
128 *
129 * <p>Implementing the Externalizable interface allows the object to assume
130 * complete control over the contents and format of the object's serialized
131 * form. The methods of the Externalizable interface, writeExternal and
132 * readExternal, are called to save and restore the objects state. When
133 * implemented by a class they can write and read their own state using all of
134 * the methods of ObjectOutput and ObjectInput. It is the responsibility of
135 * the objects to handle any versioning that occurs.
136 *
137 * <p>Enum constants are serialized differently than ordinary serializable or
138 * externalizable objects. The serialized form of an enum constant consists
139 * solely of its name; field values of the constant are not transmitted. To
140 * serialize an enum constant, ObjectOutputStream writes the string returned by
141 * the constant's name method. Like other serializable or externalizable
142 * objects, enum constants can function as the targets of back references
143 * appearing subsequently in the serialization stream. The process by which
144 * enum constants are serialized cannot be customized; any class-specific
145 * writeObject and writeReplace methods defined by enum types are ignored
146 * during serialization. Similarly, any serialPersistentFields or
147 * serialVersionUID field declarations are also ignored--all enum types have a
148 * fixed serialVersionUID of 0L.
149 *
150 * <p>Primitive data, excluding serializable fields and externalizable data, is
151 * written to the ObjectOutputStream in block-data records. A block data record
152 * is composed of a header and data. The block data header consists of a marker
153 * and the number of bytes to follow the header. Consecutive primitive data
154 * writes are merged into one block-data record. The blocking factor used for
155 * a block-data record will be 1024 bytes. Each block-data record will be
156 * filled up to 1024 bytes, or be written whenever there is a termination of
157 * block-data mode. Calls to the ObjectOutputStream methods writeObject,
158 * defaultWriteObject and writeFields initially terminate any existing
159 * block-data record.
160 *
161 * <p>Records are serialized differently than ordinary serializable or externalizable
162 * objects, see <a href="ObjectInputStream.html#record-serialization">record serialization</a>.
163 *
164 * @spec serialization/index.html Java Object Serialization Specification
165 * @author Mike Warres
166 * @author Roger Riggs
167 * @see java.io.DataOutput
168 * @see java.io.ObjectInputStream
169 * @see java.io.Serializable
170 * @see java.io.Externalizable
171 * @see <a href="{@docRoot}/../specs/serialization/output.html">
172 * <cite>Java Object Serialization Specification,</cite> Section 2, "Object Output Classes"</a>
173 * @since 1.1
174 */
175 public class ObjectOutputStream
176 extends OutputStream implements ObjectOutput, ObjectStreamConstants
177 {
178 private static final JavaLangAccess JLA = SharedSecrets.getJavaLangAccess();
179
180 private static class Caches {
181 /** cache of subclass security audit results */
182 static final ClassValue<Boolean> subclassAudits =
183 new ClassValue<>() {
184 @Override
185 protected Boolean computeValue(Class<?> type) {
186 return auditSubclass(type);
187 }
188 };
189 }
190
191 /** filter stream for handling block data conversion */
192 private final BlockDataOutputStream bout;
193 /** obj -> wire handle map */
194 private final HandleTable handles;
195 /** obj -> replacement obj map */
196 private final ReplaceTable subs;
197 /** stream protocol version */
198 private int protocol = PROTOCOL_VERSION_2;
199 /** recursion depth */
200 private int depth;
201
202 /** buffer for writing primitive field values */
203 private byte[] primVals;
204
205 /** if true, invoke writeObjectOverride() instead of writeObject() */
206 private final boolean enableOverride;
207 /** if true, invoke replaceObject() */
208 private boolean enableReplace;
209
210 // values below valid only during upcalls to writeObject()/writeExternal()
211 /**
212 * Context during upcalls to class-defined writeObject methods; holds
213 * object currently being serialized and descriptor for current class.
214 * Null when not during writeObject upcall.
215 */
216 private SerialCallbackContext curContext;
217 /** current PutField object */
218 private PutFieldImpl curPut;
219
220 /** custom storage for debug trace info */
221 private final DebugTraceInfoStack debugInfoStack;
222
223 /**
224 * value of "sun.io.serialization.extendedDebugInfo" property,
225 * as true or false for extended information about exception's place
226 */
227 @SuppressWarnings("removal")
228 private static final boolean extendedDebugInfo =
229 java.security.AccessController.doPrivileged(
230 new sun.security.action.GetBooleanAction(
231 "sun.io.serialization.extendedDebugInfo")).booleanValue();
232
233 /**
234 * Creates an ObjectOutputStream that writes to the specified OutputStream.
235 * This constructor writes the serialization stream header to the
236 * underlying stream; callers may wish to flush the stream immediately to
237 * ensure that constructors for receiving ObjectInputStreams will not block
238 * when reading the header.
239 *
240 * <p>If a security manager is installed, this constructor will check for
241 * the "enableSubclassImplementation" SerializablePermission when invoked
242 * directly or indirectly by the constructor of a subclass which overrides
243 * the ObjectOutputStream.putFields or ObjectOutputStream.writeUnshared
244 * methods.
245 *
246 * @param out output stream to write to
247 * @throws IOException if an I/O error occurs while writing stream header
248 * @throws SecurityException if untrusted subclass illegally overrides
249 * security-sensitive methods
250 * @throws NullPointerException if {@code out} is {@code null}
251 * @since 1.4
252 * @see ObjectOutputStream#ObjectOutputStream()
253 * @see ObjectOutputStream#putFields()
254 * @see ObjectInputStream#ObjectInputStream(InputStream)
255 */
256 @SuppressWarnings("this-escape")
257 public ObjectOutputStream(OutputStream out) throws IOException {
258 verifySubclass();
259 bout = new BlockDataOutputStream(out);
260 handles = new HandleTable(10, (float) 3.00);
261 subs = new ReplaceTable(10, (float) 3.00);
262 enableOverride = false;
263 writeStreamHeader();
264 bout.setBlockDataMode(true);
265 if (extendedDebugInfo) {
266 debugInfoStack = new DebugTraceInfoStack();
267 } else {
268 debugInfoStack = null;
269 }
270 }
271
272 /**
273 * Provide a way for subclasses that are completely reimplementing
274 * ObjectOutputStream to not have to allocate private data just used by
275 * this implementation of ObjectOutputStream.
276 *
277 * <p>If there is a security manager installed, this method first calls the
278 * security manager's {@code checkPermission} method with a
279 * {@code SerializablePermission("enableSubclassImplementation")}
280 * permission to ensure it's ok to enable subclassing.
281 *
282 * @throws SecurityException if a security manager exists and its
283 * {@code checkPermission} method denies enabling
284 * subclassing.
285 * @throws IOException if an I/O error occurs while creating this stream
286 * @see SecurityManager#checkPermission
287 * @see java.io.SerializablePermission
288 */
289 protected ObjectOutputStream() throws IOException, SecurityException {
290 @SuppressWarnings("removal")
291 SecurityManager sm = System.getSecurityManager();
292 if (sm != null) {
293 sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION);
294 }
295 bout = null;
296 handles = null;
297 subs = null;
298 enableOverride = true;
299 debugInfoStack = null;
300 }
301
302 /**
303 * Specify stream protocol version to use when writing the stream.
304 *
305 * <p>This routine provides a hook to enable the current version of
306 * Serialization to write in a format that is backwards compatible to a
307 * previous version of the stream format.
308 *
309 * <p>Every effort will be made to avoid introducing additional
310 * backwards incompatibilities; however, sometimes there is no
311 * other alternative.
312 *
313 * @param version use ProtocolVersion from java.io.ObjectStreamConstants.
314 * @throws IllegalStateException if called after any objects
315 * have been serialized.
316 * @throws IllegalArgumentException if invalid version is passed in.
317 * @throws IOException if I/O errors occur
318 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_1
319 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_2
320 * @since 1.2
321 */
322 public void useProtocolVersion(int version) throws IOException {
323 if (handles.size() != 0) {
324 // REMIND: implement better check for pristine stream?
325 throw new IllegalStateException("stream non-empty");
326 }
327 switch (version) {
328 case PROTOCOL_VERSION_1:
329 case PROTOCOL_VERSION_2:
330 protocol = version;
331 break;
332
333 default:
334 throw new IllegalArgumentException(
335 "unknown version: " + version);
336 }
337 }
338
339 /**
340 * Write the specified object to the ObjectOutputStream. The class of the
341 * object, the signature of the class, and the values of the non-transient
342 * and non-static fields of the class and all of its supertypes are
343 * written. Default serialization for a class can be overridden using the
344 * writeObject and the readObject methods. Objects referenced by this
345 * object are written transitively so that a complete equivalent graph of
346 * objects can be reconstructed by an ObjectInputStream.
347 *
348 * <p>Exceptions are thrown for problems with the OutputStream and for
349 * classes that should not be serialized. All exceptions are fatal to the
350 * OutputStream, which is left in an indeterminate state, and it is up to
351 * the caller to ignore or recover the stream state.
352 *
353 * @throws InvalidClassException Something is wrong with a class used by
354 * serialization.
355 * @throws NotSerializableException Some object to be serialized does not
356 * implement the java.io.Serializable interface.
357 * @throws IOException Any exception thrown by the underlying
358 * OutputStream.
359 */
360 public final void writeObject(Object obj) throws IOException {
361 if (enableOverride) {
362 writeObjectOverride(obj);
363 return;
364 }
365 try {
366 writeObject0(obj, false);
367 } catch (IOException ex) {
368 if (depth == 0) {
369 writeFatalException(ex);
370 }
371 throw ex;
372 }
373 }
374
375 /**
376 * Method used by subclasses to override the default writeObject method.
377 * This method is called by trusted subclasses of ObjectOutputStream that
378 * constructed ObjectOutputStream using the protected no-arg constructor.
379 * The subclass is expected to provide an override method with the modifier
380 * "final".
381 *
382 * @param obj object to be written to the underlying stream
383 * @throws IOException if there are I/O errors while writing to the
384 * underlying stream
385 * @see #ObjectOutputStream()
386 * @see #writeObject(Object)
387 * @since 1.2
388 */
389 protected void writeObjectOverride(Object obj) throws IOException {
390 }
391
392 /**
393 * Writes an "unshared" object to the ObjectOutputStream. This method is
394 * identical to writeObject, except that it always writes the given object
395 * as a new, unique object in the stream (as opposed to a back-reference
396 * pointing to a previously serialized instance). Specifically:
397 * <ul>
398 * <li>An object written via writeUnshared is always serialized in the
399 * same manner as a newly appearing object (an object that has not
400 * been written to the stream yet), regardless of whether or not the
401 * object has been written previously.
402 *
403 * <li>If writeObject is used to write an object that has been previously
404 * written with writeUnshared, the previous writeUnshared operation
405 * is treated as if it were a write of a separate object. In other
406 * words, ObjectOutputStream will never generate back-references to
407 * object data written by calls to writeUnshared.
408 * </ul>
409 * While writing an object via writeUnshared does not in itself guarantee a
410 * unique reference to the object when it is deserialized, it allows a
411 * single object to be defined multiple times in a stream, so that multiple
412 * calls to readUnshared by the receiver will not conflict. Note that the
413 * rules described above only apply to the base-level object written with
414 * writeUnshared, and not to any transitively referenced sub-objects in the
415 * object graph to be serialized.
416 *
417 * <p>ObjectOutputStream subclasses which override this method can only be
418 * constructed in security contexts possessing the
419 * "enableSubclassImplementation" SerializablePermission; any attempt to
420 * instantiate such a subclass without this permission will cause a
421 * SecurityException to be thrown.
422 *
423 * @param obj object to write to stream
424 * @throws NotSerializableException if an object in the graph to be
425 * serialized does not implement the Serializable interface
426 * @throws InvalidClassException if a problem exists with the class of an
427 * object to be serialized
428 * @throws IOException if an I/O error occurs during serialization
429 * @since 1.4
430 */
431 public void writeUnshared(Object obj) throws IOException {
432 try {
433 writeObject0(obj, true);
434 } catch (IOException ex) {
435 if (depth == 0) {
436 writeFatalException(ex);
437 }
438 throw ex;
439 }
440 }
441
442 /**
443 * Write the non-static and non-transient fields of the current class to
444 * this stream. This may only be called from the writeObject method of the
445 * class being serialized. It will throw the NotActiveException if it is
446 * called otherwise.
447 *
448 * @throws IOException if I/O errors occur while writing to the underlying
449 * {@code OutputStream}
450 */
451 public void defaultWriteObject() throws IOException {
452 SerialCallbackContext ctx = curContext;
453 if (ctx == null) {
454 throw new NotActiveException("not in call to writeObject");
455 }
456 Object curObj = ctx.getObj();
457 ObjectStreamClass curDesc = ctx.getDesc();
458 bout.setBlockDataMode(false);
459 defaultWriteFields(curObj, curDesc);
460 bout.setBlockDataMode(true);
461 }
462
463 /**
464 * Retrieve the object used to buffer persistent fields to be written to
465 * the stream. The fields will be written to the stream when writeFields
466 * method is called.
467 *
468 * @return an instance of the class Putfield that holds the serializable
469 * fields
470 * @throws IOException if I/O errors occur
471 * @since 1.2
472 */
473 public ObjectOutputStream.PutField putFields() throws IOException {
474 if (curPut == null) {
475 SerialCallbackContext ctx = curContext;
476 if (ctx == null) {
477 throw new NotActiveException("not in call to writeObject");
478 }
479 ctx.checkAndSetUsed();
480 ObjectStreamClass curDesc = ctx.getDesc();
481 curPut = new PutFieldImpl(curDesc);
482 }
483 return curPut;
484 }
485
486 /**
487 * Write the buffered fields to the stream.
488 *
489 * @throws IOException if I/O errors occur while writing to the underlying
490 * stream
491 * @throws NotActiveException Called when a classes writeObject method was
492 * not called to write the state of the object.
493 * @since 1.2
494 */
495 public void writeFields() throws IOException {
496 if (curPut == null) {
497 throw new NotActiveException("no current PutField object");
498 }
499 bout.setBlockDataMode(false);
500 curPut.writeFields();
501 bout.setBlockDataMode(true);
502 }
503
504 /**
505 * Reset will disregard the state of any objects already written to the
506 * stream. The state is reset to be the same as a new ObjectOutputStream.
507 * The current point in the stream is marked as reset so the corresponding
508 * ObjectInputStream will be reset at the same point. Objects previously
509 * written to the stream will not be referred to as already being in the
510 * stream. They will be written to the stream again.
511 *
512 * @throws IOException if reset() is invoked while serializing an object.
513 */
514 public void reset() throws IOException {
515 if (depth != 0) {
516 throw new IOException("stream active");
517 }
518 bout.setBlockDataMode(false);
519 bout.writeByte(TC_RESET);
520 clear();
521 bout.setBlockDataMode(true);
522 }
523
524 /**
525 * Subclasses may implement this method to allow class data to be stored in
526 * the stream. By default this method does nothing. The corresponding
527 * method in ObjectInputStream is resolveClass. This method is called
528 * exactly once for each unique class in the stream. The class name and
529 * signature will have already been written to the stream. This method may
530 * make free use of the ObjectOutputStream to save any representation of
531 * the class it deems suitable (for example, the bytes of the class file).
532 * The resolveClass method in the corresponding subclass of
533 * ObjectInputStream must read and use any data or objects written by
534 * annotateClass.
535 *
536 * @param cl the class to annotate custom data for
537 * @throws IOException Any exception thrown by the underlying
538 * OutputStream.
539 */
540 protected void annotateClass(Class<?> cl) throws IOException {
541 }
542
543 /**
544 * Subclasses may implement this method to store custom data in the stream
545 * along with descriptors for dynamic proxy classes.
546 *
547 * <p>This method is called exactly once for each unique proxy class
548 * descriptor in the stream. The default implementation of this method in
549 * {@code ObjectOutputStream} does nothing.
550 *
551 * <p>The corresponding method in {@code ObjectInputStream} is
552 * {@code resolveProxyClass}. For a given subclass of
553 * {@code ObjectOutputStream} that overrides this method, the
554 * {@code resolveProxyClass} method in the corresponding subclass of
555 * {@code ObjectInputStream} must read any data or objects written by
556 * {@code annotateProxyClass}.
557 *
558 * @param cl the proxy class to annotate custom data for
559 * @throws IOException any exception thrown by the underlying
560 * {@code OutputStream}
561 * @see ObjectInputStream#resolveProxyClass(String[])
562 * @since 1.3
563 */
564 protected void annotateProxyClass(Class<?> cl) throws IOException {
565 }
566
567 /**
568 * This method will allow trusted subclasses of ObjectOutputStream to
569 * substitute one object for another during serialization. Replacing
570 * objects is disabled until enableReplaceObject is called. The
571 * enableReplaceObject method checks that the stream requesting to do
572 * replacement can be trusted. The first occurrence of each object written
573 * into the serialization stream is passed to replaceObject. Subsequent
574 * references to the object are replaced by the object returned by the
575 * original call to replaceObject. To ensure that the private state of
576 * objects is not unintentionally exposed, only trusted streams may use
577 * replaceObject.
578 *
579 * <p>The ObjectOutputStream.writeObject method takes a parameter of type
580 * Object (as opposed to type Serializable) to allow for cases where
581 * non-serializable objects are replaced by serializable ones.
582 *
583 * <p>When a subclass is replacing objects it must ensure that either a
584 * complementary substitution must be made during deserialization or that
585 * the substituted object is compatible with every field where the
586 * reference will be stored. Objects whose type is not a subclass of the
587 * type of the field or array element abort the serialization by raising an
588 * exception and the object is not be stored.
589 *
590 * <p>This method is called only once when each object is first
591 * encountered. All subsequent references to the object will be redirected
592 * to the new object. This method should return the object to be
593 * substituted or the original object.
594 *
595 * <p>Null can be returned as the object to be substituted, but may cause
596 * {@link NullPointerException} in classes that contain references to the
597 * original object since they may be expecting an object instead of
598 * null.
599 *
600 * @param obj the object to be replaced
601 * @return the alternate object that replaced the specified one
602 * @throws IOException Any exception thrown by the underlying
603 * OutputStream.
604 */
605 protected Object replaceObject(Object obj) throws IOException {
606 return obj;
607 }
608
609 /**
610 * Enables the stream to do replacement of objects written to the stream. When
611 * enabled, the {@link #replaceObject} method is called for every object being
612 * serialized.
613 *
614 * <p>If object replacement is currently not enabled, and
615 * {@code enable} is true, and there is a security manager installed,
616 * this method first calls the security manager's
617 * {@code checkPermission} method with the
618 * {@code SerializablePermission("enableSubstitution")} permission to
619 * ensure that the caller is permitted to enable the stream to do replacement
620 * of objects written to the stream.
621 *
622 * @param enable true for enabling use of {@code replaceObject} for
623 * every object being serialized
624 * @return the previous setting before this method was invoked
625 * @throws SecurityException if a security manager exists and its
626 * {@code checkPermission} method denies enabling the stream
627 * to do replacement of objects written to the stream.
628 * @see SecurityManager#checkPermission
629 * @see java.io.SerializablePermission
630 */
631 protected boolean enableReplaceObject(boolean enable)
632 throws SecurityException
633 {
634 if (enable == enableReplace) {
635 return enable;
636 }
637 if (enable) {
638 @SuppressWarnings("removal")
639 SecurityManager sm = System.getSecurityManager();
640 if (sm != null) {
641 sm.checkPermission(SUBSTITUTION_PERMISSION);
642 }
643 }
644 enableReplace = enable;
645 return !enableReplace;
646 }
647
648 /**
649 * The writeStreamHeader method is provided so subclasses can append or
650 * prepend their own header to the stream. It writes the magic number and
651 * version to the stream.
652 *
653 * @throws IOException if I/O errors occur while writing to the underlying
654 * stream
655 */
656 protected void writeStreamHeader() throws IOException {
657 bout.writeShort(STREAM_MAGIC);
658 bout.writeShort(STREAM_VERSION);
659 }
660
661 /**
662 * Write the specified class descriptor to the ObjectOutputStream. Class
663 * descriptors are used to identify the classes of objects written to the
664 * stream. Subclasses of ObjectOutputStream may override this method to
665 * customize the way in which class descriptors are written to the
666 * serialization stream. The corresponding method in ObjectInputStream,
667 * {@link ObjectInputStream#readClassDescriptor readClassDescriptor}, should then be overridden to
668 * reconstitute the class descriptor from its custom stream representation.
669 * By default, this method writes class descriptors according to the format
670 * defined in the <a href="{@docRoot}/../specs/serialization/index.html">
671 * <cite>Java Object Serialization Specification</cite></a>.
672 *
673 * <p>Note that this method will only be called if the ObjectOutputStream
674 * is not using the old serialization stream format (set by calling
675 * ObjectOutputStream's {@code useProtocolVersion} method). If this
676 * serialization stream is using the old format
677 * ({@code PROTOCOL_VERSION_1}), the class descriptor will be written
678 * internally in a manner that cannot be overridden or customized.
679 *
680 * @param desc class descriptor to write to the stream
681 * @throws IOException If an I/O error has occurred.
682 * @spec serialization/index.html Java Object Serialization Specification
683 * @see java.io.ObjectInputStream#readClassDescriptor()
684 * @see #useProtocolVersion(int)
685 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_1
686 * @since 1.3
687 */
688 protected void writeClassDescriptor(ObjectStreamClass desc)
689 throws IOException
690 {
691 desc.writeNonProxy(this);
692 }
693
694 /**
695 * Writes a byte. This method will block until the byte is actually
696 * written.
697 *
698 * @param val the byte to be written to the stream
699 * @throws IOException If an I/O error has occurred.
700 */
701 @Override
702 public void write(int val) throws IOException {
703 bout.write(val);
704 }
705
706 /**
707 * Writes an array of bytes. This method will block until the bytes are
708 * actually written.
709 *
710 * @param buf the data to be written
711 * @throws IOException If an I/O error has occurred.
712 */
713 @Override
714 public void write(byte[] buf) throws IOException {
715 bout.write(buf, 0, buf.length, false);
716 }
717
718 /**
719 * Writes a sub array of bytes.
720 *
721 * @param buf the data to be written
722 * @param off the start offset in the data
723 * @param len the number of bytes that are written
724 * @throws IOException {@inheritDoc}
725 * @throws IndexOutOfBoundsException {@inheritDoc}
726 */
727 @Override
728 public void write(byte[] buf, int off, int len) throws IOException {
729 if (buf == null) {
730 throw new NullPointerException();
731 }
732 Objects.checkFromIndexSize(off, len, buf.length);
733 bout.write(buf, off, len, false);
734 }
735
736 /**
737 * Flushes the stream. This will write any buffered output bytes and flush
738 * through to the underlying stream.
739 *
740 * @throws IOException {@inheritDoc}
741 */
742 @Override
743 public void flush() throws IOException {
744 bout.flush();
745 }
746
747 /**
748 * Drain any buffered data in ObjectOutputStream. Similar to flush but
749 * does not propagate the flush to the underlying stream.
750 *
751 * @throws IOException if I/O errors occur while writing to the underlying
752 * stream
753 */
754 protected void drain() throws IOException {
755 bout.drain();
756 }
757
758 /**
759 * Closes the stream. This method must be called to release any resources
760 * associated with the stream.
761 *
762 * @throws IOException If an I/O error has occurred.
763 */
764 @Override
765 public void close() throws IOException {
766 flush();
767 clear();
768 bout.close();
769 }
770
771 /**
772 * Writes a boolean.
773 *
774 * @param val the boolean to be written
775 * @throws IOException if I/O errors occur while writing to the underlying
776 * stream
777 */
778 public void writeBoolean(boolean val) throws IOException {
779 bout.writeBoolean(val);
780 }
781
782 /**
783 * Writes an 8-bit byte.
784 *
785 * @param val the byte value to be written
786 * @throws IOException if I/O errors occur while writing to the underlying
787 * stream
788 */
789 public void writeByte(int val) throws IOException {
790 bout.writeByte(val);
791 }
792
793 /**
794 * Writes a 16-bit short.
795 *
796 * @param val the short value to be written
797 * @throws IOException if I/O errors occur while writing to the underlying
798 * stream
799 */
800 public void writeShort(int val) throws IOException {
801 bout.writeShort(val);
802 }
803
804 /**
805 * Writes a 16-bit char.
806 *
807 * @param val the char value to be written
808 * @throws IOException if I/O errors occur while writing to the underlying
809 * stream
810 */
811 public void writeChar(int val) throws IOException {
812 bout.writeChar(val);
813 }
814
815 /**
816 * Writes a 32-bit int.
817 *
818 * @param val the integer value to be written
819 * @throws IOException if I/O errors occur while writing to the underlying
820 * stream
821 */
822 public void writeInt(int val) throws IOException {
823 bout.writeInt(val);
824 }
825
826 /**
827 * Writes a 64-bit long.
828 *
829 * @param val the long value to be written
830 * @throws IOException if I/O errors occur while writing to the underlying
831 * stream
832 */
833 public void writeLong(long val) throws IOException {
834 bout.writeLong(val);
835 }
836
837 /**
838 * Writes a 32-bit float.
839 *
840 * @param val the float value to be written
841 * @throws IOException if I/O errors occur while writing to the underlying
842 * stream
843 */
844 public void writeFloat(float val) throws IOException {
845 bout.writeFloat(val);
846 }
847
848 /**
849 * Writes a 64-bit double.
850 *
851 * @param val the double value to be written
852 * @throws IOException if I/O errors occur while writing to the underlying
853 * stream
854 */
855 public void writeDouble(double val) throws IOException {
856 bout.writeDouble(val);
857 }
858
859 /**
860 * Writes a String as a sequence of bytes.
861 *
862 * @param str the String of bytes to be written
863 * @throws IOException if I/O errors occur while writing to the underlying
864 * stream
865 */
866 public void writeBytes(String str) throws IOException {
867 bout.writeBytes(str);
868 }
869
870 /**
871 * Writes a String as a sequence of chars.
872 *
873 * @param str the String of chars to be written
874 * @throws IOException if I/O errors occur while writing to the underlying
875 * stream
876 */
877 public void writeChars(String str) throws IOException {
878 bout.writeChars(str);
879 }
880
881 /**
882 * Primitive data write of this String in
883 * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
884 * format. Note that there is a
885 * significant difference between writing a String into the stream as
886 * primitive data or as an Object. A String instance written by writeObject
887 * is written into the stream as a String initially. Future writeObject()
888 * calls write references to the string into the stream.
889 *
890 * @param str the String to be written
891 * @throws IOException if I/O errors occur while writing to the underlying
892 * stream
893 */
894 public void writeUTF(String str) throws IOException {
895 bout.writeUTFInternal(str, false);
896 }
897
898 /**
899 * Provide programmatic access to the persistent fields to be written
900 * to ObjectOutput.
901 *
902 * @since 1.2
903 */
904 public abstract static class PutField {
905 /**
906 * Constructor for subclasses to call.
907 */
908 public PutField() {}
909
910 /**
911 * Put the value of the named boolean field into the persistent field.
912 *
913 * @param name the name of the serializable field
914 * @param val the value to assign to the field
915 * @throws IllegalArgumentException if {@code name} does not
916 * match the name of a serializable field for the class whose fields
917 * are being written, or if the type of the named field is not
918 * {@code boolean}
919 */
920 public abstract void put(String name, boolean val);
921
922 /**
923 * Put the value of the named byte field into the persistent field.
924 *
925 * @param name the name of the serializable field
926 * @param val the value to assign to the field
927 * @throws IllegalArgumentException if {@code name} does not
928 * match the name of a serializable field for the class whose fields
929 * are being written, or if the type of the named field is not
930 * {@code byte}
931 */
932 public abstract void put(String name, byte val);
933
934 /**
935 * Put the value of the named char field into the persistent field.
936 *
937 * @param name the name of the serializable field
938 * @param val the value to assign to the field
939 * @throws IllegalArgumentException if {@code name} does not
940 * match the name of a serializable field for the class whose fields
941 * are being written, or if the type of the named field is not
942 * {@code char}
943 */
944 public abstract void put(String name, char val);
945
946 /**
947 * Put the value of the named short field into the persistent field.
948 *
949 * @param name the name of the serializable field
950 * @param val the value to assign to the field
951 * @throws IllegalArgumentException if {@code name} does not
952 * match the name of a serializable field for the class whose fields
953 * are being written, or if the type of the named field is not
954 * {@code short}
955 */
956 public abstract void put(String name, short val);
957
958 /**
959 * Put the value of the named int field into the persistent field.
960 *
961 * @param name the name of the serializable field
962 * @param val the value to assign to the field
963 * @throws IllegalArgumentException if {@code name} does not
964 * match the name of a serializable field for the class whose fields
965 * are being written, or if the type of the named field is not
966 * {@code int}
967 */
968 public abstract void put(String name, int val);
969
970 /**
971 * Put the value of the named long field into the persistent field.
972 *
973 * @param name the name of the serializable field
974 * @param val the value to assign to the field
975 * @throws IllegalArgumentException if {@code name} does not
976 * match the name of a serializable field for the class whose fields
977 * are being written, or if the type of the named field is not
978 * {@code long}
979 */
980 public abstract void put(String name, long val);
981
982 /**
983 * Put the value of the named float field into the persistent field.
984 *
985 * @param name the name of the serializable field
986 * @param val the value to assign to the field
987 * @throws IllegalArgumentException if {@code name} does not
988 * match the name of a serializable field for the class whose fields
989 * are being written, or if the type of the named field is not
990 * {@code float}
991 */
992 public abstract void put(String name, float val);
993
994 /**
995 * Put the value of the named double field into the persistent field.
996 *
997 * @param name the name of the serializable field
998 * @param val the value to assign to the field
999 * @throws IllegalArgumentException if {@code name} does not
1000 * match the name of a serializable field for the class whose fields
1001 * are being written, or if the type of the named field is not
1002 * {@code double}
1003 */
1004 public abstract void put(String name, double val);
1005
1006 /**
1007 * Put the value of the named Object field into the persistent field.
1008 *
1009 * @param name the name of the serializable field
1010 * @param val the value to assign to the field
1011 * (which may be {@code null})
1012 * @throws IllegalArgumentException if {@code name} does not
1013 * match the name of a serializable field for the class whose fields
1014 * are being written, or if the type of the named field is not a
1015 * reference type
1016 */
1017 public abstract void put(String name, Object val);
1018
1019 /**
1020 * Write the data and fields to the specified ObjectOutput stream,
1021 * which must be the same stream that produced this
1022 * {@code PutField} object.
1023 *
1024 * @param out the stream to write the data and fields to
1025 * @throws IOException if I/O errors occur while writing to the
1026 * underlying stream
1027 * @throws IllegalArgumentException if the specified stream is not
1028 * the same stream that produced this {@code PutField}
1029 * object
1030 * @deprecated This method does not write the values contained by this
1031 * {@code PutField} object in a proper format, and may
1032 * result in corruption of the serialization stream. The
1033 * correct way to write {@code PutField} data is by
1034 * calling the {@link java.io.ObjectOutputStream#writeFields()}
1035 * method.
1036 */
1037 @Deprecated(forRemoval = true, since = "1.4")
1038 public abstract void write(ObjectOutput out) throws IOException;
1039 }
1040
1041
1042 /**
1043 * Returns protocol version in use.
1044 */
1045 int getProtocolVersion() {
1046 return protocol;
1047 }
1048
1049 /**
1050 * Writes string without allowing it to be replaced in stream. Used by
1051 * ObjectStreamClass to write class descriptor type strings.
1052 */
1053 void writeTypeString(String str) throws IOException {
1054 int handle;
1055 if (str == null) {
1056 writeNull();
1057 } else if ((handle = handles.lookup(str)) != -1) {
1058 writeHandle(handle);
1059 } else {
1060 writeString(str, false);
1061 }
1062 }
1063
1064 /**
1065 * Verifies that this (possibly subclass) instance can be constructed
1066 * without violating security constraints: the subclass must not override
1067 * security-sensitive non-final methods, or else the
1068 * "enableSubclassImplementation" SerializablePermission is checked.
1069 */
1070 private void verifySubclass() {
1071 Class<?> cl = getClass();
1072 if (cl == ObjectOutputStream.class) {
1073 return;
1074 }
1075 @SuppressWarnings("removal")
1076 SecurityManager sm = System.getSecurityManager();
1077 if (sm == null) {
1078 return;
1079 }
1080 boolean result = Caches.subclassAudits.get(cl);
1081 if (!result) {
1082 sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION);
1083 }
1084 }
1085
1086 /**
1087 * Performs reflective checks on given subclass to verify that it doesn't
1088 * override security-sensitive non-final methods. Returns TRUE if subclass
1089 * is "safe", FALSE otherwise.
1090 */
1091 @SuppressWarnings("removal")
1092 private static Boolean auditSubclass(Class<?> subcl) {
1093 return AccessController.doPrivileged(
1094 new PrivilegedAction<>() {
1095 public Boolean run() {
1096 for (Class<?> cl = subcl;
1097 cl != ObjectOutputStream.class;
1098 cl = cl.getSuperclass())
1099 {
1100 try {
1101 cl.getDeclaredMethod(
1102 "writeUnshared", new Class<?>[] { Object.class });
1103 return Boolean.FALSE;
1104 } catch (NoSuchMethodException ex) {
1105 }
1106 try {
1107 cl.getDeclaredMethod("putFields", (Class<?>[]) null);
1108 return Boolean.FALSE;
1109 } catch (NoSuchMethodException ex) {
1110 }
1111 }
1112 return Boolean.TRUE;
1113 }
1114 }
1115 );
1116 }
1117
1118 /**
1119 * Clears internal data structures.
1120 */
1121 private void clear() {
1122 subs.clear();
1123 handles.clear();
1124 }
1125
1126 /**
1127 * Underlying writeObject/writeUnshared implementation.
1128 */
1129 private void writeObject0(Object obj, boolean unshared)
1130 throws IOException
1131 {
1132 boolean oldMode = bout.setBlockDataMode(false);
1133 depth++;
1134 try {
1135 // handle previously written and non-replaceable objects
1136 int h;
1137 if ((obj = subs.lookup(obj)) == null) {
1138 writeNull();
1139 return;
1140 } else if (!unshared && (h = handles.lookup(obj)) != -1) {
1141 writeHandle(h);
1142 return;
1143 } else if (obj instanceof Class) {
1144 writeClass((Class) obj, unshared);
1145 return;
1146 } else if (obj instanceof ObjectStreamClass) {
1147 writeClassDesc((ObjectStreamClass) obj, unshared);
1148 return;
1149 }
1150
1151 // check for replacement object
1152 Object orig = obj;
1153 Class<?> cl = obj.getClass();
1154 ObjectStreamClass desc;
1155 for (;;) {
1156 // REMIND: skip this check for strings/arrays?
1157 Class<?> repCl;
1158 desc = ObjectStreamClass.lookup(cl, true);
1159 if (!desc.hasWriteReplaceMethod() ||
1160 (obj = desc.invokeWriteReplace(obj)) == null ||
1161 (repCl = obj.getClass()) == cl)
1162 {
1163 break;
1164 }
1165 cl = repCl;
1166 }
1167 if (enableReplace) {
1168 Object rep = replaceObject(obj);
1169 if (rep != obj && rep != null) {
1170 cl = rep.getClass();
1171 desc = ObjectStreamClass.lookup(cl, true);
1172 }
1173 obj = rep;
1174 }
1175
1176 // if object replaced, run through original checks a second time
1177 if (obj != orig) {
1178 subs.assign(orig, obj);
1179 if (obj == null) {
1180 writeNull();
1181 return;
1182 } else if (!unshared && (h = handles.lookup(obj)) != -1) {
1183 writeHandle(h);
1184 return;
1185 } else if (obj instanceof Class) {
1186 writeClass((Class) obj, unshared);
1187 return;
1188 } else if (obj instanceof ObjectStreamClass) {
1189 writeClassDesc((ObjectStreamClass) obj, unshared);
1190 return;
1191 }
1192 }
1193
1194 // remaining cases
1195 if (obj instanceof String) {
1196 writeString((String) obj, unshared);
1197 } else if (cl.isArray()) {
1198 writeArray(obj, desc, unshared);
1199 } else if (obj instanceof Enum) {
1200 writeEnum((Enum<?>) obj, desc, unshared);
1201 } else if (obj instanceof Serializable) {
1202 writeOrdinaryObject(obj, desc, unshared);
1203 } else {
1204 if (extendedDebugInfo) {
1205 throw new NotSerializableException(
1206 cl.getName() + "\n" + debugInfoStack.toString());
1207 } else {
1208 throw new NotSerializableException(cl.getName());
1209 }
1210 }
1211 } finally {
1212 depth--;
1213 bout.setBlockDataMode(oldMode);
1214 }
1215 }
1216
1217 /**
1218 * Writes null code to stream.
1219 */
1220 private void writeNull() throws IOException {
1221 bout.writeByte(TC_NULL);
1222 }
1223
1224 /**
1225 * Writes given object handle to stream.
1226 */
1227 private void writeHandle(int handle) throws IOException {
1228 bout.writeByte(TC_REFERENCE);
1229 bout.writeInt(baseWireHandle + handle);
1230 }
1231
1232 /**
1233 * Writes representation of given class to stream.
1234 */
1235 private void writeClass(Class<?> cl, boolean unshared) throws IOException {
1236 bout.writeByte(TC_CLASS);
1237 writeClassDesc(ObjectStreamClass.lookup(cl, true), false);
1238 handles.assign(unshared ? null : cl);
1239 }
1240
1241 /**
1242 * Writes representation of given class descriptor to stream.
1243 */
1244 private void writeClassDesc(ObjectStreamClass desc, boolean unshared)
1245 throws IOException
1246 {
1247 int handle;
1248 if (desc == null) {
1249 writeNull();
1250 } else if (!unshared && (handle = handles.lookup(desc)) != -1) {
1251 writeHandle(handle);
1252 } else if (desc.isProxy()) {
1253 writeProxyDesc(desc, unshared);
1254 } else {
1255 writeNonProxyDesc(desc, unshared);
1256 }
1257 }
1258
1259 private boolean isCustomSubclass() {
1260 // Return true if this class is a custom subclass of ObjectOutputStream
1261 return getClass().getClassLoader()
1262 != ObjectOutputStream.class.getClassLoader();
1263 }
1264
1265 /**
1266 * Writes class descriptor representing a dynamic proxy class to stream.
1267 */
1268 private void writeProxyDesc(ObjectStreamClass desc, boolean unshared)
1269 throws IOException
1270 {
1271 bout.writeByte(TC_PROXYCLASSDESC);
1272 handles.assign(unshared ? null : desc);
1273
1274 Class<?> cl = desc.forClass();
1275 Class<?>[] ifaces = cl.getInterfaces();
1276 bout.writeInt(ifaces.length);
1277 for (int i = 0; i < ifaces.length; i++) {
1278 bout.writeUTF(ifaces[i].getName());
1279 }
1280
1281 bout.setBlockDataMode(true);
1282 if (isCustomSubclass()) {
1283 ReflectUtil.checkPackageAccess(cl);
1284 }
1285 annotateProxyClass(cl);
1286 bout.setBlockDataMode(false);
1287 bout.writeByte(TC_ENDBLOCKDATA);
1288
1289 writeClassDesc(desc.getSuperDesc(), false);
1290 }
1291
1292 /**
1293 * Writes class descriptor representing a standard (i.e., not a dynamic
1294 * proxy) class to stream.
1295 */
1296 private void writeNonProxyDesc(ObjectStreamClass desc, boolean unshared)
1297 throws IOException
1298 {
1299 bout.writeByte(TC_CLASSDESC);
1300 handles.assign(unshared ? null : desc);
1301
1302 if (protocol == PROTOCOL_VERSION_1) {
1303 // do not invoke class descriptor write hook with old protocol
1304 desc.writeNonProxy(this);
1305 } else {
1306 writeClassDescriptor(desc);
1307 }
1308
1309 Class<?> cl = desc.forClass();
1310 bout.setBlockDataMode(true);
1311 if (cl != null && isCustomSubclass()) {
1312 ReflectUtil.checkPackageAccess(cl);
1313 }
1314 annotateClass(cl);
1315 bout.setBlockDataMode(false);
1316 bout.writeByte(TC_ENDBLOCKDATA);
1317
1318 writeClassDesc(desc.getSuperDesc(), false);
1319 }
1320
1321 /**
1322 * Writes given string to stream, using standard or long UTF format
1323 * depending on string length.
1324 */
1325 private void writeString(String str, boolean unshared) throws IOException {
1326 handles.assign(unshared ? null : str);
1327 bout.writeUTFInternal(str, true);
1328 }
1329
1330 /**
1331 * Writes given array object to stream.
1332 */
1333 private void writeArray(Object array,
1334 ObjectStreamClass desc,
1335 boolean unshared)
1336 throws IOException
1337 {
1338 bout.writeByte(TC_ARRAY);
1339 writeClassDesc(desc, false);
1340 handles.assign(unshared ? null : array);
1341
1342 Class<?> ccl = desc.forClass().getComponentType();
1343 if (ccl.isPrimitive()) {
1344 if (ccl == Integer.TYPE) {
1345 int[] ia = (int[]) array;
1346 bout.writeInt(ia.length);
1347 bout.writeInts(ia, 0, ia.length);
1348 } else if (ccl == Byte.TYPE) {
1349 byte[] ba = (byte[]) array;
1350 bout.writeInt(ba.length);
1351 bout.write(ba, 0, ba.length, true);
1352 } else if (ccl == Long.TYPE) {
1353 long[] ja = (long[]) array;
1354 bout.writeInt(ja.length);
1355 bout.writeLongs(ja, 0, ja.length);
1356 } else if (ccl == Float.TYPE) {
1357 float[] fa = (float[]) array;
1358 bout.writeInt(fa.length);
1359 bout.writeFloats(fa, 0, fa.length);
1360 } else if (ccl == Double.TYPE) {
1361 double[] da = (double[]) array;
1362 bout.writeInt(da.length);
1363 bout.writeDoubles(da, 0, da.length);
1364 } else if (ccl == Short.TYPE) {
1365 short[] sa = (short[]) array;
1366 bout.writeInt(sa.length);
1367 bout.writeShorts(sa, 0, sa.length);
1368 } else if (ccl == Character.TYPE) {
1369 char[] ca = (char[]) array;
1370 bout.writeInt(ca.length);
1371 bout.writeChars(ca, 0, ca.length);
1372 } else if (ccl == Boolean.TYPE) {
1373 boolean[] za = (boolean[]) array;
1374 bout.writeInt(za.length);
1375 bout.writeBooleans(za, 0, za.length);
1376 } else {
1377 throw new InternalError();
1378 }
1379 } else {
1380 Object[] objs = (Object[]) array;
1381 int len = objs.length;
1382 bout.writeInt(len);
1383 if (extendedDebugInfo) {
1384 debugInfoStack.push(
1385 "array (class \"" + array.getClass().getName() +
1386 "\", size: " + len + ")");
1387 }
1388 try {
1389 for (int i = 0; i < len; i++) {
1390 if (extendedDebugInfo) {
1391 debugInfoStack.push(
1392 "element of array (index: " + i + ")");
1393 }
1394 try {
1395 writeObject0(objs[i], false);
1396 } finally {
1397 if (extendedDebugInfo) {
1398 debugInfoStack.pop();
1399 }
1400 }
1401 }
1402 } finally {
1403 if (extendedDebugInfo) {
1404 debugInfoStack.pop();
1405 }
1406 }
1407 }
1408 }
1409
1410 /**
1411 * Writes given enum constant to stream.
1412 */
1413 private void writeEnum(Enum<?> en,
1414 ObjectStreamClass desc,
1415 boolean unshared)
1416 throws IOException
1417 {
1418 bout.writeByte(TC_ENUM);
1419 ObjectStreamClass sdesc = desc.getSuperDesc();
1420 writeClassDesc((sdesc.forClass() == Enum.class) ? desc : sdesc, false);
1421 handles.assign(unshared ? null : en);
1422 writeString(en.name(), false);
1423 }
1424
1425 /**
1426 * Writes representation of an "ordinary" (i.e., not a String, Class,
1427 * ObjectStreamClass, array, or enum constant) serializable object to the
1428 * stream.
1429 */
1430 private void writeOrdinaryObject(Object obj,
1431 ObjectStreamClass desc,
1432 boolean unshared)
1433 throws IOException
1434 {
1435 if (extendedDebugInfo) {
1436 debugInfoStack.push(
1437 (depth == 1 ? "root " : "") + "object (class \"" +
1438 obj.getClass().getName() + "\", " + obj.toString() + ")");
1439 }
1440 try {
1441 desc.checkSerialize();
1442
1443 bout.writeByte(TC_OBJECT);
1444 writeClassDesc(desc, false);
1445 handles.assign(unshared ? null : obj);
1446
1447 if (desc.isRecord()) {
1448 writeRecordData(obj, desc);
1449 } else if (desc.isExternalizable() && !desc.isProxy()) {
1450 writeExternalData((Externalizable) obj);
1451 } else {
1452 writeSerialData(obj, desc);
1453 }
1454 } finally {
1455 if (extendedDebugInfo) {
1456 debugInfoStack.pop();
1457 }
1458 }
1459 }
1460
1461 /**
1462 * Writes externalizable data of given object by invoking its
1463 * writeExternal() method.
1464 */
1465 private void writeExternalData(Externalizable obj) throws IOException {
1466 PutFieldImpl oldPut = curPut;
1467 curPut = null;
1468
1469 if (extendedDebugInfo) {
1470 debugInfoStack.push("writeExternal data");
1471 }
1472 SerialCallbackContext oldContext = curContext;
1473 try {
1474 curContext = null;
1475 if (protocol == PROTOCOL_VERSION_1) {
1476 obj.writeExternal(this);
1477 } else {
1478 bout.setBlockDataMode(true);
1479 obj.writeExternal(this);
1480 bout.setBlockDataMode(false);
1481 bout.writeByte(TC_ENDBLOCKDATA);
1482 }
1483 } finally {
1484 curContext = oldContext;
1485 if (extendedDebugInfo) {
1486 debugInfoStack.pop();
1487 }
1488 }
1489
1490 curPut = oldPut;
1491 }
1492
1493 /** Writes the record component values for the given record object. */
1494 private void writeRecordData(Object obj, ObjectStreamClass desc)
1495 throws IOException
1496 {
1497 assert obj.getClass().isRecord();
1498 ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout();
1499 if (slots.length != 1) {
1500 throw new InvalidClassException(
1501 "expected a single record slot length, but found: " + slots.length);
1502 }
1503
1504 defaultWriteFields(obj, desc); // #### seems unnecessary to use the accessors
1505 }
1506
1507 /**
1508 * Writes instance data for each serializable class of given object, from
1509 * superclass to subclass.
1510 */
1511 private void writeSerialData(Object obj, ObjectStreamClass desc)
1512 throws IOException
1513 {
1514 ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout();
1515 for (int i = 0; i < slots.length; i++) {
1516 ObjectStreamClass slotDesc = slots[i].desc;
1517 if (slotDesc.hasWriteObjectMethod()) {
1518 PutFieldImpl oldPut = curPut;
1519 curPut = null;
1520 SerialCallbackContext oldContext = curContext;
1521
1522 if (extendedDebugInfo) {
1523 debugInfoStack.push(
1524 "custom writeObject data (class \"" +
1525 slotDesc.getName() + "\")");
1526 }
1527 try {
1528 curContext = new SerialCallbackContext(obj, slotDesc);
1529 bout.setBlockDataMode(true);
1530 slotDesc.invokeWriteObject(obj, this);
1531 bout.setBlockDataMode(false);
1532 bout.writeByte(TC_ENDBLOCKDATA);
1533 } finally {
1534 curContext.setUsed();
1535 curContext = oldContext;
1536 if (extendedDebugInfo) {
1537 debugInfoStack.pop();
1538 }
1539 }
1540
1541 curPut = oldPut;
1542 } else {
1543 defaultWriteFields(obj, slotDesc);
1544 }
1545 }
1546 }
1547
1548 /**
1549 * Fetches and writes values of serializable fields of given object to
1550 * stream. The given class descriptor specifies which field values to
1551 * write, and in which order they should be written.
1552 */
1553 private void defaultWriteFields(Object obj, ObjectStreamClass desc)
1554 throws IOException
1555 {
1556 Class<?> cl = desc.forClass();
1557 if (cl != null && obj != null && !cl.isInstance(obj)) {
1558 throw new ClassCastException();
1559 }
1560
1561 desc.checkDefaultSerialize();
1562
1563 int primDataSize = desc.getPrimDataSize();
1564 if (primDataSize > 0) {
1565 if (primVals == null || primVals.length < primDataSize) {
1566 primVals = new byte[primDataSize];
1567 }
1568 desc.getPrimFieldValues(obj, primVals);
1569 bout.write(primVals, 0, primDataSize, false);
1570 }
1571
1572 int numObjFields = desc.getNumObjFields();
1573 if (numObjFields > 0) {
1574 ObjectStreamField[] fields = desc.getFields(false);
1575 Object[] objVals = new Object[numObjFields];
1576 int numPrimFields = fields.length - objVals.length;
1577 desc.getObjFieldValues(obj, objVals);
1578 for (int i = 0; i < objVals.length; i++) {
1579 if (extendedDebugInfo) {
1580 debugInfoStack.push(
1581 "field (class \"" + desc.getName() + "\", name: \"" +
1582 fields[numPrimFields + i].getName() + "\", type: \"" +
1583 fields[numPrimFields + i].getType() + "\")");
1584 }
1585 try {
1586 writeObject0(objVals[i],
1587 fields[numPrimFields + i].isUnshared());
1588 } finally {
1589 if (extendedDebugInfo) {
1590 debugInfoStack.pop();
1591 }
1592 }
1593 }
1594 }
1595 }
1596
1597 /**
1598 * Attempts to write to stream fatal IOException that has caused
1599 * serialization to abort.
1600 */
1601 private void writeFatalException(IOException ex) throws IOException {
1602 /*
1603 * Note: the serialization specification states that if a second
1604 * IOException occurs while attempting to serialize the original fatal
1605 * exception to the stream, then a StreamCorruptedException should be
1606 * thrown (section 2.1). However, due to a bug in previous
1607 * implementations of serialization, StreamCorruptedExceptions were
1608 * rarely (if ever) actually thrown--the "root" exceptions from
1609 * underlying streams were thrown instead. This historical behavior is
1610 * followed here for consistency.
1611 */
1612 clear();
1613 boolean oldMode = bout.setBlockDataMode(false);
1614 try {
1615 bout.writeByte(TC_EXCEPTION);
1616 writeObject0(ex, false);
1617 clear();
1618 } finally {
1619 bout.setBlockDataMode(oldMode);
1620 }
1621 }
1622
1623 /**
1624 * Default PutField implementation.
1625 */
1626 private class PutFieldImpl extends PutField {
1627
1628 /** class descriptor describing serializable fields */
1629 private final ObjectStreamClass desc;
1630 /** primitive field values */
1631 private final byte[] primVals;
1632 /** object field values */
1633 private final Object[] objVals;
1634
1635 /**
1636 * Creates PutFieldImpl object for writing fields defined in given
1637 * class descriptor.
1638 */
1639 PutFieldImpl(ObjectStreamClass desc) {
1640 this.desc = desc;
1641 primVals = new byte[desc.getPrimDataSize()];
1642 objVals = new Object[desc.getNumObjFields()];
1643 }
1644
1645 public void put(String name, boolean val) {
1646 ByteArray.setBoolean(primVals, getFieldOffset(name, Boolean.TYPE), val);
1647 }
1648
1649 public void put(String name, byte val) {
1650 primVals[getFieldOffset(name, Byte.TYPE)] = val;
1651 }
1652
1653 public void put(String name, char val) {
1654 ByteArray.setChar(primVals, getFieldOffset(name, Character.TYPE), val);
1655 }
1656
1657 public void put(String name, short val) {
1658 ByteArray.setShort(primVals, getFieldOffset(name, Short.TYPE), val);
1659 }
1660
1661 public void put(String name, int val) {
1662 ByteArray.setInt(primVals, getFieldOffset(name, Integer.TYPE), val);
1663 }
1664
1665 public void put(String name, float val) {
1666 ByteArray.setFloat(primVals, getFieldOffset(name, Float.TYPE), val);
1667 }
1668
1669 public void put(String name, long val) {
1670 ByteArray.setLong(primVals, getFieldOffset(name, Long.TYPE), val);
1671 }
1672
1673 public void put(String name, double val) {
1674 ByteArray.setDouble(primVals, getFieldOffset(name, Double.TYPE), val);
1675 }
1676
1677 public void put(String name, Object val) {
1678 objVals[getFieldOffset(name, Object.class)] = val;
1679 }
1680
1681 // deprecated in ObjectOutputStream.PutField
1682 public void write(ObjectOutput out) throws IOException {
1683 /*
1684 * Applications should *not* use this method to write PutField
1685 * data, as it will lead to stream corruption if the PutField
1686 * object writes any primitive data (since block data mode is not
1687 * unset/set properly, as is done in OOS.writeFields()). This
1688 * broken implementation is being retained solely for behavioral
1689 * compatibility, in order to support applications which use
1690 * OOS.PutField.write() for writing only non-primitive data.
1691 *
1692 * Serialization of unshared objects is not implemented here since
1693 * it is not necessary for backwards compatibility; also, unshared
1694 * semantics may not be supported by the given ObjectOutput
1695 * instance. Applications which write unshared objects using the
1696 * PutField API must use OOS.writeFields().
1697 */
1698 if (ObjectOutputStream.this != out) {
1699 throw new IllegalArgumentException("wrong stream");
1700 }
1701 out.write(primVals, 0, primVals.length);
1702
1703 ObjectStreamField[] fields = desc.getFields(false);
1704 int numPrimFields = fields.length - objVals.length;
1705 // REMIND: warn if numPrimFields > 0?
1706 for (int i = 0; i < objVals.length; i++) {
1707 if (fields[numPrimFields + i].isUnshared()) {
1708 throw new IOException("cannot write unshared object");
1709 }
1710 out.writeObject(objVals[i]);
1711 }
1712 }
1713
1714 /**
1715 * Writes buffered primitive data and object fields to stream.
1716 */
1717 void writeFields() throws IOException {
1718 bout.write(primVals, 0, primVals.length, false);
1719
1720 ObjectStreamField[] fields = desc.getFields(false);
1721 int numPrimFields = fields.length - objVals.length;
1722 for (int i = 0; i < objVals.length; i++) {
1723 if (extendedDebugInfo) {
1724 debugInfoStack.push(
1725 "field (class \"" + desc.getName() + "\", name: \"" +
1726 fields[numPrimFields + i].getName() + "\", type: \"" +
1727 fields[numPrimFields + i].getType() + "\")");
1728 }
1729 try {
1730 writeObject0(objVals[i],
1731 fields[numPrimFields + i].isUnshared());
1732 } finally {
1733 if (extendedDebugInfo) {
1734 debugInfoStack.pop();
1735 }
1736 }
1737 }
1738 }
1739
1740 /**
1741 * Returns offset of field with given name and type. A specified type
1742 * of null matches all types, Object.class matches all non-primitive
1743 * types, and any other non-null type matches assignable types only.
1744 * Throws IllegalArgumentException if no matching field found.
1745 */
1746 private int getFieldOffset(String name, Class<?> type) {
1747 ObjectStreamField field = desc.getField(name, type);
1748 if (field == null) {
1749 throw new IllegalArgumentException("no such field " + name +
1750 " with type " + type);
1751 }
1752 return field.getOffset();
1753 }
1754 }
1755
1756 /**
1757 * Buffered output stream with two modes: in default mode, outputs data in
1758 * same format as DataOutputStream; in "block data" mode, outputs data
1759 * bracketed by block data markers (see object serialization specification
1760 * for details).
1761 */
1762 private static final class BlockDataOutputStream
1763 extends OutputStream implements DataOutput
1764 {
1765 /** maximum data block length */
1766 private static final int MAX_BLOCK_SIZE = 1024;
1767 /** maximum data block header length */
1768 private static final int MAX_HEADER_SIZE = 5;
1769 /** (tunable) length of char buffer (for writing strings) */
1770 private static final int CHAR_BUF_SIZE = 256;
1771
1772 /** buffer for writing general/block data */
1773 private final byte[] buf = new byte[MAX_BLOCK_SIZE];
1774 /** buffer for writing block data headers */
1775 private final byte[] hbuf = new byte[MAX_HEADER_SIZE];
1776 /** char buffer for fast string writes */
1777 private final char[] cbuf = new char[CHAR_BUF_SIZE];
1778
1779 /** block data mode */
1780 private boolean blkmode = false;
1781 /** current offset into buf */
1782 private int pos = 0;
1783
1784 /** underlying output stream */
1785 private final OutputStream out;
1786 /** loopback stream (for data writes that span data blocks) */
1787 private final DataOutputStream dout;
1788
1789 /**
1790 * Creates new BlockDataOutputStream on top of given underlying stream.
1791 * Block data mode is turned off by default.
1792 */
1793 BlockDataOutputStream(OutputStream out) {
1794 this.out = out;
1795 dout = new DataOutputStream(this);
1796 }
1797
1798 /**
1799 * Sets block data mode to the given mode (true == on, false == off)
1800 * and returns the previous mode value. If the new mode is the same as
1801 * the old mode, no action is taken. If the new mode differs from the
1802 * old mode, any buffered data is flushed before switching to the new
1803 * mode.
1804 */
1805 boolean setBlockDataMode(boolean mode) throws IOException {
1806 if (blkmode == mode) {
1807 return blkmode;
1808 }
1809 drain();
1810 blkmode = mode;
1811 return !blkmode;
1812 }
1813
1814 /**
1815 * Returns true if the stream is currently in block data mode, false
1816 * otherwise.
1817 */
1818 boolean getBlockDataMode() {
1819 return blkmode;
1820 }
1821
1822 /* ----------------- generic output stream methods ----------------- */
1823 /*
1824 * The following methods are equivalent to their counterparts in
1825 * OutputStream, except that they partition written data into data
1826 * blocks when in block data mode.
1827 */
1828
1829 public void write(int b) throws IOException {
1830 if (pos >= MAX_BLOCK_SIZE) {
1831 drain();
1832 }
1833 buf[pos++] = (byte) b;
1834 }
1835
1836 public void write(byte[] b) throws IOException {
1837 write(b, 0, b.length, false);
1838 }
1839
1840 public void write(byte[] b, int off, int len) throws IOException {
1841 write(b, off, len, false);
1842 }
1843
1844 public void flush() throws IOException {
1845 drain();
1846 out.flush();
1847 }
1848
1849 public void close() throws IOException {
1850 flush();
1851 out.close();
1852 }
1853
1854 /**
1855 * Writes specified span of byte values from given array. If copy is
1856 * true, copies the values to an intermediate buffer before writing
1857 * them to underlying stream (to avoid exposing a reference to the
1858 * original byte array).
1859 */
1860 void write(byte[] b, int off, int len, boolean copy)
1861 throws IOException
1862 {
1863 if (!(copy || blkmode)) { // write directly
1864 drain();
1865 out.write(b, off, len);
1866 return;
1867 }
1868
1869 while (len > 0) {
1870 if (pos >= MAX_BLOCK_SIZE) {
1871 drain();
1872 }
1873 if (len >= MAX_BLOCK_SIZE && !copy && pos == 0) {
1874 // avoid unnecessary copy
1875 writeBlockHeader(MAX_BLOCK_SIZE);
1876 out.write(b, off, MAX_BLOCK_SIZE);
1877 off += MAX_BLOCK_SIZE;
1878 len -= MAX_BLOCK_SIZE;
1879 } else {
1880 int wlen = Math.min(len, MAX_BLOCK_SIZE - pos);
1881 System.arraycopy(b, off, buf, pos, wlen);
1882 pos += wlen;
1883 off += wlen;
1884 len -= wlen;
1885 }
1886 }
1887 }
1888
1889 /**
1890 * Writes all buffered data from this stream to the underlying stream,
1891 * but does not flush underlying stream.
1892 */
1893 void drain() throws IOException {
1894 if (pos == 0) {
1895 return;
1896 }
1897 if (blkmode) {
1898 writeBlockHeader(pos);
1899 }
1900 out.write(buf, 0, pos);
1901 pos = 0;
1902 }
1903
1904 /**
1905 * Writes block data header. Data blocks shorter than 256 bytes are
1906 * prefixed with a 2-byte header; all others start with a 5-byte
1907 * header.
1908 */
1909 private void writeBlockHeader(int len) throws IOException {
1910 if (len <= 0xFF) {
1911 hbuf[0] = TC_BLOCKDATA;
1912 hbuf[1] = (byte) len;
1913 out.write(hbuf, 0, 2);
1914 } else {
1915 hbuf[0] = TC_BLOCKDATALONG;
1916 ByteArray.setInt(hbuf, 1, len);
1917 out.write(hbuf, 0, 5);
1918 }
1919 }
1920
1921
1922 /* ----------------- primitive data output methods ----------------- */
1923 /*
1924 * The following methods are equivalent to their counterparts in
1925 * DataOutputStream, except that they partition written data into data
1926 * blocks when in block data mode.
1927 */
1928
1929 public void writeBoolean(boolean v) throws IOException {
1930 if (pos >= MAX_BLOCK_SIZE) {
1931 drain();
1932 }
1933 ByteArray.setBoolean(buf, pos++, v);
1934 }
1935
1936 public void writeByte(int v) throws IOException {
1937 if (pos >= MAX_BLOCK_SIZE) {
1938 drain();
1939 }
1940 buf[pos++] = (byte) v;
1941 }
1942
1943 public void writeChar(int v) throws IOException {
1944 if (pos + 2 <= MAX_BLOCK_SIZE) {
1945 ByteArray.setChar(buf, pos, (char) v);
1946 pos += 2;
1947 } else {
1948 dout.writeChar(v);
1949 }
1950 }
1951
1952 public void writeShort(int v) throws IOException {
1953 if (pos + 2 <= MAX_BLOCK_SIZE) {
1954 ByteArray.setShort(buf, pos, (short) v);
1955 pos += 2;
1956 } else {
1957 dout.writeShort(v);
1958 }
1959 }
1960
1961 public void writeInt(int v) throws IOException {
1962 if (pos + 4 <= MAX_BLOCK_SIZE) {
1963 ByteArray.setInt(buf, pos, v);
1964 pos += 4;
1965 } else {
1966 dout.writeInt(v);
1967 }
1968 }
1969
1970 public void writeFloat(float v) throws IOException {
1971 if (pos + 4 <= MAX_BLOCK_SIZE) {
1972 ByteArray.setFloat(buf, pos, v);
1973 pos += 4;
1974 } else {
1975 dout.writeFloat(v);
1976 }
1977 }
1978
1979 public void writeLong(long v) throws IOException {
1980 if (pos + 8 <= MAX_BLOCK_SIZE) {
1981 ByteArray.setLong(buf, pos, v);
1982 pos += 8;
1983 } else {
1984 dout.writeLong(v);
1985 }
1986 }
1987
1988 public void writeDouble(double v) throws IOException {
1989 if (pos + 8 <= MAX_BLOCK_SIZE) {
1990 ByteArray.setDouble(buf, pos, v);
1991 pos += 8;
1992 } else {
1993 dout.writeDouble(v);
1994 }
1995 }
1996
1997 @SuppressWarnings("deprecation")
1998 void writeBytes(String s, int len) throws IOException {
1999 int pos = this.pos;
2000 for (int strpos = 0; strpos < len;) {
2001 int rem = MAX_BLOCK_SIZE - pos;
2002 int csize = Math.min(len - strpos, rem);
2003 s.getBytes(strpos, strpos + csize, buf, pos);
2004 pos += csize;
2005 strpos += csize;
2006
2007 if (pos == MAX_BLOCK_SIZE) {
2008 this.pos = pos;
2009 drain();
2010 pos = 0;
2011 }
2012 }
2013 this.pos = pos;
2014 }
2015
2016 public void writeBytes(String s) throws IOException {
2017 writeBytes(s, s.length());
2018 }
2019
2020 public void writeChars(String s) throws IOException {
2021 int endoff = s.length();
2022 for (int off = 0; off < endoff; ) {
2023 int csize = Math.min(endoff - off, CHAR_BUF_SIZE);
2024 s.getChars(off, off + csize, cbuf, 0);
2025 writeChars(cbuf, 0, csize);
2026 off += csize;
2027 }
2028 }
2029
2030 public void writeUTF(String str) throws IOException {
2031 writeUTFInternal(str, false);
2032 }
2033
2034 private void writeUTFInternal(String str, boolean writeHeader) throws IOException {
2035 int strlen = str.length();
2036 int countNonZeroAscii = JLA.countNonZeroAscii(str);
2037 int utflen = utfLen(str, countNonZeroAscii);
2038 if (utflen <= 0xFFFF) {
2039 if(writeHeader) {
2040 writeByte(TC_STRING);
2041 }
2042 writeShort(utflen);
2043 } else {
2044 if(writeHeader) {
2045 writeByte(TC_LONGSTRING);
2046 }
2047 writeLong(utflen);
2048 }
2049
2050 if (countNonZeroAscii != 0) {
2051 writeBytes(str, countNonZeroAscii);
2052 }
2053 if (countNonZeroAscii != strlen) {
2054 writeMoreUTF(str, countNonZeroAscii);
2055 }
2056 }
2057
2058 private void writeMoreUTF(String str, int stroff) throws IOException {
2059 int pos = this.pos;
2060 for (int strlen = str.length(); stroff < strlen;) {
2061 char c = str.charAt(stroff++);
2062 int csize = c != 0 && c < 0x80 ? 1 : c >= 0x800 ? 3 : 2;
2063 if (pos + csize >= MAX_BLOCK_SIZE) {
2064 this.pos = pos;
2065 drain();
2066 pos = 0;
2067 }
2068 pos = putChar(buf, pos, c);
2069 }
2070 this.pos = pos;
2071 }
2072
2073
2074 /* -------------- primitive data array output methods -------------- */
2075 /*
2076 * The following methods write out spans of primitive data values.
2077 * Though equivalent to calling the corresponding primitive write
2078 * methods repeatedly, these methods are optimized for writing groups
2079 * of primitive data values more efficiently.
2080 */
2081
2082 void writeBooleans(boolean[] v, int off, int len) throws IOException {
2083 int endoff = off + len;
2084 while (off < endoff) {
2085 if (pos >= MAX_BLOCK_SIZE) {
2086 drain();
2087 }
2088 int stop = Math.min(endoff, off + (MAX_BLOCK_SIZE - pos));
2089 while (off < stop) {
2090 ByteArray.setBoolean(buf, pos++, v[off++]);
2091 }
2092 }
2093 }
2094
2095 void writeChars(char[] v, int off, int len) throws IOException {
2096 int limit = MAX_BLOCK_SIZE - 2;
2097 int endoff = off + len;
2098 while (off < endoff) {
2099 if (pos <= limit) {
2100 int avail = (MAX_BLOCK_SIZE - pos) >> 1;
2101 int stop = Math.min(endoff, off + avail);
2102 while (off < stop) {
2103 ByteArray.setChar(buf, pos, v[off++]);
2104 pos += 2;
2105 }
2106 } else {
2107 dout.writeChar(v[off++]);
2108 }
2109 }
2110 }
2111
2112 void writeShorts(short[] v, int off, int len) throws IOException {
2113 int limit = MAX_BLOCK_SIZE - 2;
2114 int endoff = off + len;
2115 while (off < endoff) {
2116 if (pos <= limit) {
2117 int avail = (MAX_BLOCK_SIZE - pos) >> 1;
2118 int stop = Math.min(endoff, off + avail);
2119 while (off < stop) {
2120 ByteArray.setShort(buf, pos, v[off++]);
2121 pos += 2;
2122 }
2123 } else {
2124 dout.writeShort(v[off++]);
2125 }
2126 }
2127 }
2128
2129 void writeInts(int[] v, int off, int len) throws IOException {
2130 int limit = MAX_BLOCK_SIZE - 4;
2131 int endoff = off + len;
2132 while (off < endoff) {
2133 if (pos <= limit) {
2134 int avail = (MAX_BLOCK_SIZE - pos) >> 2;
2135 int stop = Math.min(endoff, off + avail);
2136 while (off < stop) {
2137 ByteArray.setInt(buf, pos, v[off++]);
2138 pos += 4;
2139 }
2140 } else {
2141 dout.writeInt(v[off++]);
2142 }
2143 }
2144 }
2145
2146 void writeFloats(float[] v, int off, int len) throws IOException {
2147 int limit = MAX_BLOCK_SIZE - 4;
2148 int endoff = off + len;
2149 while (off < endoff) {
2150 if (pos <= limit) {
2151 int avail = (MAX_BLOCK_SIZE - pos) >> 2;
2152 int stop = Math.min(endoff, off + avail);
2153 while (off < stop) {
2154 ByteArray.setFloat(buf, pos, v[off++]);
2155 pos += 4;
2156 }
2157 } else {
2158 dout.writeFloat(v[off++]);
2159 }
2160 }
2161 }
2162
2163 void writeLongs(long[] v, int off, int len) throws IOException {
2164 int limit = MAX_BLOCK_SIZE - 8;
2165 int endoff = off + len;
2166 while (off < endoff) {
2167 if (pos <= limit) {
2168 int avail = (MAX_BLOCK_SIZE - pos) >> 3;
2169 int stop = Math.min(endoff, off + avail);
2170 while (off < stop) {
2171 ByteArray.setLong(buf, pos, v[off++]);
2172 pos += 8;
2173 }
2174 } else {
2175 dout.writeLong(v[off++]);
2176 }
2177 }
2178 }
2179
2180 void writeDoubles(double[] v, int off, int len) throws IOException {
2181 int limit = MAX_BLOCK_SIZE - 8;
2182 int endoff = off + len;
2183 while (off < endoff) {
2184 if (pos <= limit) {
2185 int avail = (MAX_BLOCK_SIZE - pos) >> 3;
2186 int stop = Math.min(endoff, off + avail);
2187 while (off < stop) {
2188 ByteArray.setDouble(buf, pos, v[off++]);
2189 pos += 8;
2190 }
2191 } else {
2192 dout.writeDouble(v[off++]);
2193 }
2194 }
2195 }
2196 }
2197
2198 /**
2199 * Lightweight identity hash table which maps objects to integer handles,
2200 * assigned in ascending order.
2201 */
2202 private static final class HandleTable {
2203
2204 /* number of mappings in table/next available handle */
2205 private int size;
2206 /* size threshold determining when to expand hash spine */
2207 private int threshold;
2208 /* factor for computing size threshold */
2209 private final float loadFactor;
2210 /* maps hash value -> candidate handle value */
2211 private int[] spine;
2212 /* maps handle value -> next candidate handle value */
2213 private int[] next;
2214 /* maps handle value -> associated object */
2215 private Object[] objs;
2216
2217 /**
2218 * Creates new HandleTable with given capacity and load factor.
2219 */
2220 HandleTable(int initialCapacity, float loadFactor) {
2221 this.loadFactor = loadFactor;
2222 spine = new int[initialCapacity];
2223 next = new int[initialCapacity];
2224 objs = new Object[initialCapacity];
2225 threshold = (int) (initialCapacity * loadFactor);
2226 clear();
2227 }
2228
2229 /**
2230 * Assigns next available handle to given object, and returns handle
2231 * value. Handles are assigned in ascending order starting at 0.
2232 */
2233 int assign(Object obj) {
2234 if (size >= next.length) {
2235 growEntries();
2236 }
2237 if (size >= threshold) {
2238 growSpine();
2239 }
2240 insert(obj, size);
2241 return size++;
2242 }
2243
2244 /**
2245 * Looks up and returns handle associated with given object, or -1 if
2246 * no mapping found.
2247 */
2248 int lookup(Object obj) {
2249 if (size == 0) {
2250 return -1;
2251 }
2252 int index = hash(obj) % spine.length;
2253 for (int i = spine[index]; i >= 0; i = next[i]) {
2254 if (objs[i] == obj) {
2255 return i;
2256 }
2257 }
2258 return -1;
2259 }
2260
2261 /**
2262 * Resets table to its initial (empty) state.
2263 */
2264 void clear() {
2265 Arrays.fill(spine, -1);
2266 Arrays.fill(objs, 0, size, null);
2267 size = 0;
2268 }
2269
2270 /**
2271 * Returns the number of mappings currently in table.
2272 */
2273 int size() {
2274 return size;
2275 }
2276
2277 /**
2278 * Inserts mapping object -> handle mapping into table. Assumes table
2279 * is large enough to accommodate new mapping.
2280 */
2281 private void insert(Object obj, int handle) {
2282 int index = hash(obj) % spine.length;
2283 objs[handle] = obj;
2284 next[handle] = spine[index];
2285 spine[index] = handle;
2286 }
2287
2288 /**
2289 * Expands the hash "spine" -- equivalent to increasing the number of
2290 * buckets in a conventional hash table.
2291 */
2292 private void growSpine() {
2293 spine = new int[(spine.length << 1) + 1];
2294 threshold = (int) (spine.length * loadFactor);
2295 Arrays.fill(spine, -1);
2296 for (int i = 0; i < size; i++) {
2297 insert(objs[i], i);
2298 }
2299 }
2300
2301 /**
2302 * Increases hash table capacity by lengthening entry arrays.
2303 */
2304 private void growEntries() {
2305 int newLength = (next.length << 1) + 1;
2306 int[] newNext = new int[newLength];
2307 System.arraycopy(next, 0, newNext, 0, size);
2308 next = newNext;
2309
2310 Object[] newObjs = new Object[newLength];
2311 System.arraycopy(objs, 0, newObjs, 0, size);
2312 objs = newObjs;
2313 }
2314
2315 /**
2316 * Returns hash value for given object.
2317 */
2318 private int hash(Object obj) {
2319 return System.identityHashCode(obj) & 0x7FFFFFFF;
2320 }
2321 }
2322
2323 /**
2324 * Lightweight identity hash table which maps objects to replacement
2325 * objects.
2326 */
2327 private static final class ReplaceTable {
2328
2329 /* maps object -> index */
2330 private final HandleTable htab;
2331 /* maps index -> replacement object */
2332 private Object[] reps;
2333
2334 /**
2335 * Creates new ReplaceTable with given capacity and load factor.
2336 */
2337 ReplaceTable(int initialCapacity, float loadFactor) {
2338 htab = new HandleTable(initialCapacity, loadFactor);
2339 reps = new Object[initialCapacity];
2340 }
2341
2342 /**
2343 * Enters mapping from object to replacement object.
2344 */
2345 void assign(Object obj, Object rep) {
2346 int index = htab.assign(obj);
2347 while (index >= reps.length) {
2348 grow();
2349 }
2350 reps[index] = rep;
2351 }
2352
2353 /**
2354 * Looks up and returns replacement for given object. If no
2355 * replacement is found, returns the lookup object itself.
2356 */
2357 Object lookup(Object obj) {
2358 int index = htab.lookup(obj);
2359 return (index >= 0) ? reps[index] : obj;
2360 }
2361
2362 /**
2363 * Resets table to its initial (empty) state.
2364 */
2365 void clear() {
2366 Arrays.fill(reps, 0, htab.size(), null);
2367 htab.clear();
2368 }
2369
2370 /**
2371 * Returns the number of mappings currently in table.
2372 */
2373 int size() {
2374 return htab.size();
2375 }
2376
2377 /**
2378 * Increases table capacity.
2379 */
2380 private void grow() {
2381 Object[] newReps = new Object[(reps.length << 1) + 1];
2382 System.arraycopy(reps, 0, newReps, 0, reps.length);
2383 reps = newReps;
2384 }
2385 }
2386
2387 /**
2388 * Stack to keep debug information about the state of the
2389 * serialization process, for embedding in exception messages.
2390 */
2391 private static final class DebugTraceInfoStack {
2392 private final List<String> stack;
2393
2394 DebugTraceInfoStack() {
2395 stack = new ArrayList<>();
2396 }
2397
2398 /**
2399 * Removes all of the elements from enclosed list.
2400 */
2401 void clear() {
2402 stack.clear();
2403 }
2404
2405 /**
2406 * Removes the object at the top of enclosed list.
2407 */
2408 void pop() {
2409 stack.remove(stack.size()-1);
2410 }
2411
2412 /**
2413 * Pushes a String onto the top of enclosed list.
2414 */
2415 void push(String entry) {
2416 stack.add("\t- " + entry);
2417 }
2418
2419 /**
2420 * Returns a string representation of this object
2421 */
2422 public String toString() {
2423 StringJoiner sj = new StringJoiner("\n");
2424 for (int i = stack.size() - 1; i >= 0; i--) {
2425 sj.add(stack.get(i));
2426 }
2427 return sj.toString();
2428 }
2429 }
2430
2431 }