1 /*
2 * Copyright (c) 1996, 2013, 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 java.io;
27
28 import java.lang.ref.Reference;
29 import java.lang.ref.ReferenceQueue;
30 import java.lang.ref.SoftReference;
31 import java.lang.ref.WeakReference;
32 import java.lang.reflect.Constructor;
33 import java.lang.reflect.Field;
34 import java.lang.reflect.InvocationTargetException;
35 import java.lang.reflect.Member;
36 import java.lang.reflect.Method;
37 import java.lang.reflect.Modifier;
38 import java.lang.reflect.Proxy;
39 import java.security.AccessController;
40 import java.security.MessageDigest;
41 import java.security.NoSuchAlgorithmException;
42 import java.security.PrivilegedAction;
43 import java.util.ArrayList;
44 import java.util.Arrays;
45 import java.util.Collections;
46 import java.util.Comparator;
47 import java.util.HashSet;
48 import java.util.Set;
49 import java.util.concurrent.ConcurrentHashMap;
50 import java.util.concurrent.ConcurrentMap;
51 import sun.misc.Unsafe;
52 import sun.reflect.CallerSensitive;
53 import sun.reflect.Reflection;
54 import sun.reflect.ReflectionFactory;
55 import sun.reflect.misc.ReflectUtil;
56
57 /**
58 * Serialization's descriptor for classes. It contains the name and
59 * serialVersionUID of the class. The ObjectStreamClass for a specific class
60 * loaded in this Java VM can be found/created using the lookup method.
61 *
62 * <p>The algorithm to compute the SerialVersionUID is described in
63 * <a href="../../../platform/serialization/spec/class.html#4100">Object
64 * Serialization Specification, Section 4.6, Stream Unique Identifiers</a>.
65 *
66 * @author Mike Warres
67 * @author Roger Riggs
68 * @see ObjectStreamField
69 * @see <a href="../../../platform/serialization/spec/class.html">Object Serialization Specification, Section 4, Class Descriptors</a>
70 * @since 1.1
71 */
72 public class ObjectStreamClass implements Serializable {
73
74 /** serialPersistentFields value indicating no serializable fields */
75 public static final ObjectStreamField[] NO_FIELDS =
76 new ObjectStreamField[0];
77
78 private static final long serialVersionUID = -6120832682080437368L;
79 private static final ObjectStreamField[] serialPersistentFields =
80 NO_FIELDS;
81
82 /** reflection factory for obtaining serialization constructors */
83 private static final ReflectionFactory reflFactory =
84 AccessController.doPrivileged(
85 new ReflectionFactory.GetReflectionFactoryAction());
86
87 private static class Caches {
88 /** cache mapping local classes -> descriptors */
89 static final ConcurrentMap<WeakClassKey,Reference<?>> localDescs =
90 new ConcurrentHashMap<>();
91
92 /** cache mapping field group/local desc pairs -> field reflectors */
93 static final ConcurrentMap<FieldReflectorKey,Reference<?>> reflectors =
94 new ConcurrentHashMap<>();
95
96 /** queue for WeakReferences to local classes */
97 private static final ReferenceQueue<Class<?>> localDescsQueue =
98 new ReferenceQueue<>();
99 /** queue for WeakReferences to field reflectors keys */
100 private static final ReferenceQueue<Class<?>> reflectorsQueue =
101 new ReferenceQueue<>();
102 }
103
104 /** class associated with this descriptor (if any) */
105 private Class<?> cl;
106 /** name of class represented by this descriptor */
107 private String name;
108 /** serialVersionUID of represented class (null if not computed yet) */
109 private volatile Long suid;
110
111 /** true if represents dynamic proxy class */
112 private boolean isProxy;
113 /** true if represents enum type */
114 private boolean isEnum;
115 /** true if represented class implements Serializable */
116 private boolean serializable;
117 /** true if represented class implements Externalizable */
118 private boolean externalizable;
119 /** true if desc has data written by class-defined writeObject method */
120 private boolean hasWriteObjectData;
121 /**
122 * true if desc has externalizable data written in block data format; this
123 * must be true by default to accommodate ObjectInputStream subclasses which
124 * override readClassDescriptor() to return class descriptors obtained from
125 * ObjectStreamClass.lookup() (see 4461737)
126 */
127 private boolean hasBlockExternalData = true;
128
129 /**
130 * Contains information about InvalidClassException instances to be thrown
131 * when attempting operations on an invalid class. Note that instances of
132 * this class are immutable and are potentially shared among
133 * ObjectStreamClass instances.
134 */
135 private static class ExceptionInfo {
136 private final String className;
137 private final String message;
138
139 ExceptionInfo(String cn, String msg) {
140 className = cn;
141 message = msg;
142 }
143
144 /**
145 * Returns (does not throw) an InvalidClassException instance created
146 * from the information in this object, suitable for being thrown by
147 * the caller.
148 */
149 InvalidClassException newInvalidClassException() {
150 return new InvalidClassException(className, message);
151 }
152 }
153
154 /** exception (if any) thrown while attempting to resolve class */
155 private ClassNotFoundException resolveEx;
156 /** exception (if any) to throw if non-enum deserialization attempted */
157 private ExceptionInfo deserializeEx;
158 /** exception (if any) to throw if non-enum serialization attempted */
159 private ExceptionInfo serializeEx;
160 /** exception (if any) to throw if default serialization attempted */
161 private ExceptionInfo defaultSerializeEx;
162
163 /** serializable fields */
164 private ObjectStreamField[] fields;
165 /** aggregate marshalled size of primitive fields */
166 private int primDataSize;
167 /** number of non-primitive fields */
168 private int numObjFields;
169 /** reflector for setting/getting serializable field values */
170 private FieldReflector fieldRefl;
171 /** data layout of serialized objects described by this class desc */
172 private volatile ClassDataSlot[] dataLayout;
173
174 /** serialization-appropriate constructor, or null if none */
175 private Constructor<?> cons;
176 /** class-defined writeObject method, or null if none */
177 private Method writeObjectMethod;
178 /** class-defined readObject method, or null if none */
179 private Method readObjectMethod;
180 /** class-defined readObjectNoData method, or null if none */
181 private Method readObjectNoDataMethod;
182 /** class-defined writeReplace method, or null if none */
183 private Method writeReplaceMethod;
184 /** class-defined readResolve method, or null if none */
185 private Method readResolveMethod;
186
187 /** local class descriptor for represented class (may point to self) */
188 private ObjectStreamClass localDesc;
189 /** superclass descriptor appearing in stream */
190 private ObjectStreamClass superDesc;
191
192 /**
193 * Initializes native code.
194 */
195 private static native void initNative();
196 static {
197 initNative();
198 }
199
200 /**
201 * Find the descriptor for a class that can be serialized. Creates an
202 * ObjectStreamClass instance if one does not exist yet for class. Null is
203 * returned if the specified class does not implement java.io.Serializable
204 * or java.io.Externalizable.
205 *
206 * @param cl class for which to get the descriptor
207 * @return the class descriptor for the specified class
208 */
209 public static ObjectStreamClass lookup(Class<?> cl) {
210 return lookup(cl, false);
211 }
212
213 /**
214 * Returns the descriptor for any class, regardless of whether it
215 * implements {@link Serializable}.
216 *
217 * @param cl class for which to get the descriptor
218 * @return the class descriptor for the specified class
219 * @since 1.6
220 */
221 public static ObjectStreamClass lookupAny(Class<?> cl) {
222 return lookup(cl, true);
223 }
224
225 /**
226 * Returns the name of the class described by this descriptor.
227 * This method returns the name of the class in the format that
228 * is used by the {@link Class#getName} method.
229 *
230 * @return a string representing the name of the class
231 */
232 public String getName() {
233 return name;
234 }
235
236 /**
237 * Return the serialVersionUID for this class. The serialVersionUID
238 * defines a set of classes all with the same name that have evolved from a
239 * common root class and agree to be serialized and deserialized using a
240 * common format. NonSerializable classes have a serialVersionUID of 0L.
241 *
242 * @return the SUID of the class described by this descriptor
243 */
244 public long getSerialVersionUID() {
245 // REMIND: synchronize instead of relying on volatile?
246 if (suid == null) {
247 suid = AccessController.doPrivileged(
248 new PrivilegedAction<Long>() {
249 public Long run() {
250 return computeDefaultSUID(cl);
251 }
252 }
253 );
254 }
255 return suid.longValue();
256 }
257
258 /**
259 * Return the class in the local VM that this version is mapped to. Null
260 * is returned if there is no corresponding local class.
261 *
262 * @return the <code>Class</code> instance that this descriptor represents
263 */
264 @CallerSensitive
265 public Class<?> forClass() {
266 if (cl == null) {
267 return null;
268 }
269 if (System.getSecurityManager() != null) {
270 Class<?> caller = Reflection.getCallerClass();
271 if (ReflectUtil.needsPackageAccessCheck(caller.getClassLoader(), cl.getClassLoader())) {
272 ReflectUtil.checkPackageAccess(cl);
273 }
274 }
275 return cl;
276 }
277
278 /**
279 * Return an array of the fields of this serializable class.
280 *
281 * @return an array containing an element for each persistent field of
282 * this class. Returns an array of length zero if there are no
283 * fields.
284 * @since 1.2
285 */
286 public ObjectStreamField[] getFields() {
287 return getFields(true);
288 }
289
290 /**
291 * Get the field of this class by name.
292 *
293 * @param name the name of the data field to look for
294 * @return The ObjectStreamField object of the named field or null if
295 * there is no such named field.
296 */
297 public ObjectStreamField getField(String name) {
298 return getField(name, null);
299 }
300
301 /**
302 * Return a string describing this ObjectStreamClass.
303 */
304 public String toString() {
305 return name + ": static final long serialVersionUID = " +
306 getSerialVersionUID() + "L;";
307 }
308
309 /**
310 * Looks up and returns class descriptor for given class, or null if class
311 * is non-serializable and "all" is set to false.
312 *
313 * @param cl class to look up
314 * @param all if true, return descriptors for all classes; if false, only
315 * return descriptors for serializable classes
316 */
317 static ObjectStreamClass lookup(Class<?> cl, boolean all) {
318 if (!(all || Serializable.class.isAssignableFrom(cl))) {
319 return null;
320 }
321 processQueue(Caches.localDescsQueue, Caches.localDescs);
322 WeakClassKey key = new WeakClassKey(cl, Caches.localDescsQueue);
323 Reference<?> ref = Caches.localDescs.get(key);
324 Object entry = null;
325 if (ref != null) {
326 entry = ref.get();
327 }
328 EntryFuture future = null;
329 if (entry == null) {
330 EntryFuture newEntry = new EntryFuture();
331 Reference<?> newRef = new SoftReference<>(newEntry);
332 do {
333 if (ref != null) {
334 Caches.localDescs.remove(key, ref);
335 }
336 ref = Caches.localDescs.putIfAbsent(key, newRef);
337 if (ref != null) {
338 entry = ref.get();
339 }
340 } while (ref != null && entry == null);
341 if (entry == null) {
342 future = newEntry;
343 }
344 }
345
346 if (entry instanceof ObjectStreamClass) { // check common case first
347 return (ObjectStreamClass) entry;
348 }
349 if (entry instanceof EntryFuture) {
350 future = (EntryFuture) entry;
351 if (future.getOwner() == Thread.currentThread()) {
352 /*
353 * Handle nested call situation described by 4803747: waiting
354 * for future value to be set by a lookup() call further up the
355 * stack will result in deadlock, so calculate and set the
356 * future value here instead.
357 */
358 entry = null;
359 } else {
360 entry = future.get();
361 }
362 }
363 if (entry == null) {
364 try {
365 entry = new ObjectStreamClass(cl);
366 } catch (Throwable th) {
367 entry = th;
368 }
369 if (future.set(entry)) {
370 Caches.localDescs.put(key, new SoftReference<Object>(entry));
371 } else {
372 // nested lookup call already set future
373 entry = future.get();
374 }
375 }
376
377 if (entry instanceof ObjectStreamClass) {
378 return (ObjectStreamClass) entry;
379 } else if (entry instanceof RuntimeException) {
380 throw (RuntimeException) entry;
381 } else if (entry instanceof Error) {
382 throw (Error) entry;
383 } else {
384 throw new InternalError("unexpected entry: " + entry);
385 }
386 }
387
388 /**
389 * Placeholder used in class descriptor and field reflector lookup tables
390 * for an entry in the process of being initialized. (Internal) callers
391 * which receive an EntryFuture belonging to another thread as the result
392 * of a lookup should call the get() method of the EntryFuture; this will
393 * return the actual entry once it is ready for use and has been set(). To
394 * conserve objects, EntryFutures synchronize on themselves.
395 */
396 private static class EntryFuture {
397
398 private static final Object unset = new Object();
399 private final Thread owner = Thread.currentThread();
400 private Object entry = unset;
401
402 /**
403 * Attempts to set the value contained by this EntryFuture. If the
404 * EntryFuture's value has not been set already, then the value is
405 * saved, any callers blocked in the get() method are notified, and
406 * true is returned. If the value has already been set, then no saving
407 * or notification occurs, and false is returned.
408 */
409 synchronized boolean set(Object entry) {
410 if (this.entry != unset) {
411 return false;
412 }
413 this.entry = entry;
414 notifyAll();
415 return true;
416 }
417
418 /**
419 * Returns the value contained by this EntryFuture, blocking if
420 * necessary until a value is set.
421 */
422 synchronized Object get() {
423 boolean interrupted = false;
424 while (entry == unset) {
425 try {
426 wait();
427 } catch (InterruptedException ex) {
428 interrupted = true;
429 }
430 }
431 if (interrupted) {
432 AccessController.doPrivileged(
433 new PrivilegedAction<Void>() {
434 public Void run() {
435 Thread.currentThread().interrupt();
436 return null;
437 }
438 }
439 );
440 }
441 return entry;
442 }
443
444 /**
445 * Returns the thread that created this EntryFuture.
446 */
447 Thread getOwner() {
448 return owner;
449 }
450 }
451
452 /**
453 * Creates local class descriptor representing given class.
454 */
455 private ObjectStreamClass(final Class<?> cl) {
456 this.cl = cl;
457 name = cl.getName();
458 isProxy = Proxy.isProxyClass(cl);
459 isEnum = Enum.class.isAssignableFrom(cl);
460 serializable = Serializable.class.isAssignableFrom(cl);
461 externalizable = Externalizable.class.isAssignableFrom(cl);
462
463 Class<?> superCl = cl.getSuperclass();
464 superDesc = (superCl != null) ? lookup(superCl, false) : null;
465 localDesc = this;
466
467 if (serializable) {
468 AccessController.doPrivileged(new PrivilegedAction<Void>() {
469 public Void run() {
470 if (isEnum) {
471 suid = Long.valueOf(0);
472 fields = NO_FIELDS;
473 return null;
474 }
475 if (cl.isArray()) {
476 fields = NO_FIELDS;
477 return null;
478 }
479
480 suid = getDeclaredSUID(cl);
481 try {
482 fields = getSerialFields(cl);
483 computeFieldOffsets();
484 } catch (InvalidClassException e) {
485 serializeEx = deserializeEx =
486 new ExceptionInfo(e.classname, e.getMessage());
487 fields = NO_FIELDS;
488 }
489
490 if (externalizable) {
491 cons = getExternalizableConstructor(cl);
492 } else {
493 cons = getSerializableConstructor(cl);
494 writeObjectMethod = getPrivateMethod(cl, "writeObject",
495 new Class<?>[] { ObjectOutputStream.class },
496 Void.TYPE);
497 readObjectMethod = getPrivateMethod(cl, "readObject",
498 new Class<?>[] { ObjectInputStream.class },
499 Void.TYPE);
500 readObjectNoDataMethod = getPrivateMethod(
501 cl, "readObjectNoData", null, Void.TYPE);
502 hasWriteObjectData = (writeObjectMethod != null);
503 }
504 writeReplaceMethod = getInheritableMethod(
505 cl, "writeReplace", null, Object.class);
506 readResolveMethod = getInheritableMethod(
507 cl, "readResolve", null, Object.class);
508 return null;
509 }
510 });
511 } else {
512 suid = Long.valueOf(0);
513 fields = NO_FIELDS;
514 }
515
516 try {
517 fieldRefl = getReflector(fields, this);
518 } catch (InvalidClassException ex) {
519 // field mismatches impossible when matching local fields vs. self
520 throw new InternalError(ex);
521 }
522
523 if (deserializeEx == null) {
524 if (isEnum) {
525 deserializeEx = new ExceptionInfo(name, "enum type");
526 } else if (cons == null) {
527 deserializeEx = new ExceptionInfo(name, "no valid constructor");
528 }
529 }
530 for (int i = 0; i < fields.length; i++) {
531 if (fields[i].getField() == null) {
532 defaultSerializeEx = new ExceptionInfo(
533 name, "unmatched serializable field(s) declared");
534 }
535 }
536 }
537
538 /**
539 * Creates blank class descriptor which should be initialized via a
540 * subsequent call to initProxy(), initNonProxy() or readNonProxy().
541 */
542 ObjectStreamClass() {
543 }
544
545 /**
546 * Initializes class descriptor representing a proxy class.
547 */
548 void initProxy(Class<?> cl,
549 ClassNotFoundException resolveEx,
550 ObjectStreamClass superDesc)
551 throws InvalidClassException
552 {
553 this.cl = cl;
554 this.resolveEx = resolveEx;
555 this.superDesc = superDesc;
556 isProxy = true;
557 serializable = true;
558 suid = Long.valueOf(0);
559 fields = NO_FIELDS;
560
561 if (cl != null) {
562 localDesc = lookup(cl, true);
563 if (!localDesc.isProxy) {
564 throw new InvalidClassException(
565 "cannot bind proxy descriptor to a non-proxy class");
566 }
567 name = localDesc.name;
568 externalizable = localDesc.externalizable;
569 cons = localDesc.cons;
570 writeReplaceMethod = localDesc.writeReplaceMethod;
571 readResolveMethod = localDesc.readResolveMethod;
572 deserializeEx = localDesc.deserializeEx;
573 }
574 fieldRefl = getReflector(fields, localDesc);
575 }
576
577 /**
578 * Initializes class descriptor representing a non-proxy class.
579 */
580 void initNonProxy(ObjectStreamClass model,
581 Class<?> cl,
582 ClassNotFoundException resolveEx,
583 ObjectStreamClass superDesc)
584 throws InvalidClassException
585 {
586 this.cl = cl;
587 this.resolveEx = resolveEx;
588 this.superDesc = superDesc;
589 name = model.name;
590 suid = Long.valueOf(model.getSerialVersionUID());
591 isProxy = false;
592 isEnum = model.isEnum;
593 serializable = model.serializable;
594 externalizable = model.externalizable;
595 hasBlockExternalData = model.hasBlockExternalData;
596 hasWriteObjectData = model.hasWriteObjectData;
597 fields = model.fields;
598 primDataSize = model.primDataSize;
599 numObjFields = model.numObjFields;
600
601 if (cl != null) {
602 localDesc = lookup(cl, true);
603 if (localDesc.isProxy) {
604 throw new InvalidClassException(
605 "cannot bind non-proxy descriptor to a proxy class");
606 }
607 if (isEnum != localDesc.isEnum) {
608 throw new InvalidClassException(isEnum ?
609 "cannot bind enum descriptor to a non-enum class" :
610 "cannot bind non-enum descriptor to an enum class");
611 }
612
613 if (serializable == localDesc.serializable &&
614 !cl.isArray() &&
615 suid.longValue() != localDesc.getSerialVersionUID())
616 {
617 throw new InvalidClassException(localDesc.name,
618 "local class incompatible: " +
619 "stream classdesc serialVersionUID = " + suid +
620 ", local class serialVersionUID = " +
621 localDesc.getSerialVersionUID());
622 }
623
624 if (!classNamesEqual(name, localDesc.name)) {
625 throw new InvalidClassException(localDesc.name,
626 "local class name incompatible with stream class " +
627 "name \"" + name + "\"");
628 }
629
630 if (!isEnum) {
631 if ((serializable == localDesc.serializable) &&
632 (externalizable != localDesc.externalizable))
633 {
634 throw new InvalidClassException(localDesc.name,
635 "Serializable incompatible with Externalizable");
636 }
637
638 if ((serializable != localDesc.serializable) ||
639 (externalizable != localDesc.externalizable) ||
640 !(serializable || externalizable))
641 {
642 deserializeEx = new ExceptionInfo(
643 localDesc.name, "class invalid for deserialization");
644 }
645 }
646
647 cons = localDesc.cons;
648 writeObjectMethod = localDesc.writeObjectMethod;
649 readObjectMethod = localDesc.readObjectMethod;
650 readObjectNoDataMethod = localDesc.readObjectNoDataMethod;
651 writeReplaceMethod = localDesc.writeReplaceMethod;
652 readResolveMethod = localDesc.readResolveMethod;
653 if (deserializeEx == null) {
654 deserializeEx = localDesc.deserializeEx;
655 }
656 }
657 fieldRefl = getReflector(fields, localDesc);
658 // reassign to matched fields so as to reflect local unshared settings
659 fields = fieldRefl.getFields();
660 }
661
662 /**
663 * Reads non-proxy class descriptor information from given input stream.
664 * The resulting class descriptor is not fully functional; it can only be
665 * used as input to the ObjectInputStream.resolveClass() and
666 * ObjectStreamClass.initNonProxy() methods.
667 */
668 void readNonProxy(ObjectInputStream in)
669 throws IOException, ClassNotFoundException
670 {
671 name = in.readUTF();
672 suid = Long.valueOf(in.readLong());
673 isProxy = false;
674
675 byte flags = in.readByte();
676 hasWriteObjectData =
677 ((flags & ObjectStreamConstants.SC_WRITE_METHOD) != 0);
678 hasBlockExternalData =
679 ((flags & ObjectStreamConstants.SC_BLOCK_DATA) != 0);
680 externalizable =
681 ((flags & ObjectStreamConstants.SC_EXTERNALIZABLE) != 0);
682 boolean sflag =
683 ((flags & ObjectStreamConstants.SC_SERIALIZABLE) != 0);
684 if (externalizable && sflag) {
685 throw new InvalidClassException(
686 name, "serializable and externalizable flags conflict");
687 }
688 serializable = externalizable || sflag;
689 isEnum = ((flags & ObjectStreamConstants.SC_ENUM) != 0);
690 if (isEnum && suid.longValue() != 0L) {
691 throw new InvalidClassException(name,
692 "enum descriptor has non-zero serialVersionUID: " + suid);
693 }
694
695 int numFields = in.readShort();
696 if (isEnum && numFields != 0) {
697 throw new InvalidClassException(name,
698 "enum descriptor has non-zero field count: " + numFields);
699 }
700 fields = (numFields > 0) ?
701 new ObjectStreamField[numFields] : NO_FIELDS;
702 for (int i = 0; i < numFields; i++) {
703 char tcode = (char) in.readByte();
704 String fname = in.readUTF();
705 String signature = ((tcode == 'L') || (tcode == '[')) ?
706 in.readTypeString() : new String(new char[] { tcode });
707 try {
708 fields[i] = new ObjectStreamField(fname, signature, false);
709 } catch (RuntimeException e) {
710 throw (IOException) new InvalidClassException(name,
711 "invalid descriptor for field " + fname).initCause(e);
712 }
713 }
714 computeFieldOffsets();
715 }
716
717 /**
718 * Writes non-proxy class descriptor information to given output stream.
719 */
720 void writeNonProxy(ObjectOutputStream out) throws IOException {
721 out.writeUTF(name);
722 out.writeLong(getSerialVersionUID());
723
724 byte flags = 0;
725 if (externalizable) {
726 flags |= ObjectStreamConstants.SC_EXTERNALIZABLE;
727 int protocol = out.getProtocolVersion();
728 if (protocol != ObjectStreamConstants.PROTOCOL_VERSION_1) {
729 flags |= ObjectStreamConstants.SC_BLOCK_DATA;
730 }
731 } else if (serializable) {
732 flags |= ObjectStreamConstants.SC_SERIALIZABLE;
733 }
734 if (hasWriteObjectData) {
735 flags |= ObjectStreamConstants.SC_WRITE_METHOD;
736 }
737 if (isEnum) {
738 flags |= ObjectStreamConstants.SC_ENUM;
739 }
740 out.writeByte(flags);
741
742 out.writeShort(fields.length);
743 for (int i = 0; i < fields.length; i++) {
744 ObjectStreamField f = fields[i];
745 out.writeByte(f.getTypeCode());
746 out.writeUTF(f.getName());
747 if (!f.isPrimitive()) {
748 out.writeTypeString(f.getTypeString());
749 }
750 }
751 }
752
753 /**
754 * Returns ClassNotFoundException (if any) thrown while attempting to
755 * resolve local class corresponding to this class descriptor.
756 */
757 ClassNotFoundException getResolveException() {
758 return resolveEx;
759 }
760
761 /**
762 * Throws an InvalidClassException if object instances referencing this
763 * class descriptor should not be allowed to deserialize. This method does
764 * not apply to deserialization of enum constants.
765 */
766 void checkDeserialize() throws InvalidClassException {
767 if (deserializeEx != null) {
768 throw deserializeEx.newInvalidClassException();
769 }
770 }
771
772 /**
773 * Throws an InvalidClassException if objects whose class is represented by
774 * this descriptor should not be allowed to serialize. This method does
775 * not apply to serialization of enum constants.
776 */
777 void checkSerialize() throws InvalidClassException {
778 if (serializeEx != null) {
779 throw serializeEx.newInvalidClassException();
780 }
781 }
782
783 /**
784 * Throws an InvalidClassException if objects whose class is represented by
785 * this descriptor should not be permitted to use default serialization
786 * (e.g., if the class declares serializable fields that do not correspond
787 * to actual fields, and hence must use the GetField API). This method
788 * does not apply to deserialization of enum constants.
789 */
790 void checkDefaultSerialize() throws InvalidClassException {
791 if (defaultSerializeEx != null) {
792 throw defaultSerializeEx.newInvalidClassException();
793 }
794 }
795
796 /**
797 * Returns superclass descriptor. Note that on the receiving side, the
798 * superclass descriptor may be bound to a class that is not a superclass
799 * of the subclass descriptor's bound class.
800 */
801 ObjectStreamClass getSuperDesc() {
802 return superDesc;
803 }
804
805 /**
806 * Returns the "local" class descriptor for the class associated with this
807 * class descriptor (i.e., the result of
808 * ObjectStreamClass.lookup(this.forClass())) or null if there is no class
809 * associated with this descriptor.
810 */
811 ObjectStreamClass getLocalDesc() {
812 return localDesc;
813 }
814
815 /**
816 * Returns arrays of ObjectStreamFields representing the serializable
817 * fields of the represented class. If copy is true, a clone of this class
818 * descriptor's field array is returned, otherwise the array itself is
819 * returned.
820 */
821 ObjectStreamField[] getFields(boolean copy) {
822 return copy ? fields.clone() : fields;
823 }
824
825 /**
826 * Looks up a serializable field of the represented class by name and type.
827 * A specified type of null matches all types, Object.class matches all
828 * non-primitive types, and any other non-null type matches assignable
829 * types only. Returns matching field, or null if no match found.
830 */
831 ObjectStreamField getField(String name, Class<?> type) {
832 for (int i = 0; i < fields.length; i++) {
833 ObjectStreamField f = fields[i];
834 if (f.getName().equals(name)) {
835 if (type == null ||
836 (type == Object.class && !f.isPrimitive()))
837 {
838 return f;
839 }
840 Class<?> ftype = f.getType();
841 if (ftype != null && type.isAssignableFrom(ftype)) {
842 return f;
843 }
844 }
845 }
846 return null;
847 }
848
849 /**
850 * Returns true if class descriptor represents a dynamic proxy class, false
851 * otherwise.
852 */
853 boolean isProxy() {
854 return isProxy;
855 }
856
857 /**
858 * Returns true if class descriptor represents an enum type, false
859 * otherwise.
860 */
861 boolean isEnum() {
862 return isEnum;
863 }
864
865 /**
866 * Returns true if represented class implements Externalizable, false
867 * otherwise.
868 */
869 boolean isExternalizable() {
870 return externalizable;
871 }
872
873 /**
874 * Returns true if represented class implements Serializable, false
875 * otherwise.
876 */
877 boolean isSerializable() {
878 return serializable;
879 }
880
881 /**
882 * Returns true if class descriptor represents externalizable class that
883 * has written its data in 1.2 (block data) format, false otherwise.
884 */
885 boolean hasBlockExternalData() {
886 return hasBlockExternalData;
887 }
888
889 /**
890 * Returns true if class descriptor represents serializable (but not
891 * externalizable) class which has written its data via a custom
892 * writeObject() method, false otherwise.
893 */
894 boolean hasWriteObjectData() {
895 return hasWriteObjectData;
896 }
897
898 /**
899 * Returns true if represented class is serializable/externalizable and can
900 * be instantiated by the serialization runtime--i.e., if it is
901 * externalizable and defines a public no-arg constructor, or if it is
902 * non-externalizable and its first non-serializable superclass defines an
903 * accessible no-arg constructor. Otherwise, returns false.
904 */
905 boolean isInstantiable() {
906 return (cons != null);
907 }
908
909 /**
910 * Returns true if represented class is serializable (but not
911 * externalizable) and defines a conformant writeObject method. Otherwise,
912 * returns false.
913 */
914 boolean hasWriteObjectMethod() {
915 return (writeObjectMethod != null);
916 }
917
918 /**
919 * Returns true if represented class is serializable (but not
920 * externalizable) and defines a conformant readObject method. Otherwise,
921 * returns false.
922 */
923 boolean hasReadObjectMethod() {
924 return (readObjectMethod != null);
925 }
926
927 /**
928 * Returns true if represented class is serializable (but not
929 * externalizable) and defines a conformant readObjectNoData method.
930 * Otherwise, returns false.
931 */
932 boolean hasReadObjectNoDataMethod() {
933 return (readObjectNoDataMethod != null);
934 }
935
936 /**
937 * Returns true if represented class is serializable or externalizable and
938 * defines a conformant writeReplace method. Otherwise, returns false.
939 */
940 boolean hasWriteReplaceMethod() {
941 return (writeReplaceMethod != null);
942 }
943
944 /**
945 * Returns true if represented class is serializable or externalizable and
946 * defines a conformant readResolve method. Otherwise, returns false.
947 */
948 boolean hasReadResolveMethod() {
949 return (readResolveMethod != null);
950 }
951
952 /**
953 * Creates a new instance of the represented class. If the class is
954 * externalizable, invokes its public no-arg constructor; otherwise, if the
955 * class is serializable, invokes the no-arg constructor of the first
956 * non-serializable superclass. Throws UnsupportedOperationException if
957 * this class descriptor is not associated with a class, if the associated
958 * class is non-serializable or if the appropriate no-arg constructor is
959 * inaccessible/unavailable.
960 */
961 Object newInstance()
962 throws InstantiationException, InvocationTargetException,
963 UnsupportedOperationException
964 {
965 if (cons != null) {
966 try {
967 return cons.newInstance();
968 } catch (IllegalAccessException ex) {
969 // should not occur, as access checks have been suppressed
970 throw new InternalError(ex);
971 }
972 } else {
973 throw new UnsupportedOperationException();
974 }
975 }
976
977 /**
978 * Invokes the writeObject method of the represented serializable class.
979 * Throws UnsupportedOperationException if this class descriptor is not
980 * associated with a class, or if the class is externalizable,
981 * non-serializable or does not define writeObject.
982 */
983 void invokeWriteObject(Object obj, ObjectOutputStream out)
984 throws IOException, UnsupportedOperationException
985 {
986 if (writeObjectMethod != null) {
987 try {
988 writeObjectMethod.invoke(obj, new Object[]{ out });
989 } catch (InvocationTargetException ex) {
990 Throwable th = ex.getTargetException();
991 if (th instanceof IOException) {
992 throw (IOException) th;
993 } else {
994 throwMiscException(th);
995 }
996 } catch (IllegalAccessException ex) {
997 // should not occur, as access checks have been suppressed
998 throw new InternalError(ex);
999 }
1000 } else {
1001 throw new UnsupportedOperationException();
1002 }
1003 }
1004
1005 /**
1006 * Invokes the readObject method of the represented serializable class.
1007 * Throws UnsupportedOperationException if this class descriptor is not
1008 * associated with a class, or if the class is externalizable,
1009 * non-serializable or does not define readObject.
1010 */
1011 void invokeReadObject(Object obj, ObjectInputStream in)
1012 throws ClassNotFoundException, IOException,
1013 UnsupportedOperationException
1014 {
1015 if (readObjectMethod != null) {
1016 try {
1017 readObjectMethod.invoke(obj, new Object[]{ in });
1018 } catch (InvocationTargetException ex) {
1019 Throwable th = ex.getTargetException();
1020 if (th instanceof ClassNotFoundException) {
1021 throw (ClassNotFoundException) th;
1022 } else if (th instanceof IOException) {
1023 throw (IOException) th;
1024 } else {
1025 throwMiscException(th);
1026 }
1027 } catch (IllegalAccessException ex) {
1028 // should not occur, as access checks have been suppressed
1029 throw new InternalError(ex);
1030 }
1031 } else {
1032 throw new UnsupportedOperationException();
1033 }
1034 }
1035
1036 /**
1037 * Invokes the readObjectNoData method of the represented serializable
1038 * class. Throws UnsupportedOperationException if this class descriptor is
1039 * not associated with a class, or if the class is externalizable,
1040 * non-serializable or does not define readObjectNoData.
1041 */
1042 void invokeReadObjectNoData(Object obj)
1043 throws IOException, UnsupportedOperationException
1044 {
1045 if (readObjectNoDataMethod != null) {
1046 try {
1047 readObjectNoDataMethod.invoke(obj, (Object[]) null);
1048 } catch (InvocationTargetException ex) {
1049 Throwable th = ex.getTargetException();
1050 if (th instanceof ObjectStreamException) {
1051 throw (ObjectStreamException) th;
1052 } else {
1053 throwMiscException(th);
1054 }
1055 } catch (IllegalAccessException ex) {
1056 // should not occur, as access checks have been suppressed
1057 throw new InternalError(ex);
1058 }
1059 } else {
1060 throw new UnsupportedOperationException();
1061 }
1062 }
1063
1064 /**
1065 * Invokes the writeReplace method of the represented serializable class and
1066 * returns the result. Throws UnsupportedOperationException if this class
1067 * descriptor is not associated with a class, or if the class is
1068 * non-serializable or does not define writeReplace.
1069 */
1070 Object invokeWriteReplace(Object obj)
1071 throws IOException, UnsupportedOperationException
1072 {
1073 if (writeReplaceMethod != null) {
1074 try {
1075 return writeReplaceMethod.invoke(obj, (Object[]) null);
1076 } catch (InvocationTargetException ex) {
1077 Throwable th = ex.getTargetException();
1078 if (th instanceof ObjectStreamException) {
1079 throw (ObjectStreamException) th;
1080 } else {
1081 throwMiscException(th);
1082 throw new InternalError(th); // never reached
1083 }
1084 } catch (IllegalAccessException ex) {
1085 // should not occur, as access checks have been suppressed
1086 throw new InternalError(ex);
1087 }
1088 } else {
1089 throw new UnsupportedOperationException();
1090 }
1091 }
1092
1093 /**
1094 * Invokes the readResolve method of the represented serializable class and
1095 * returns the result. Throws UnsupportedOperationException if this class
1096 * descriptor is not associated with a class, or if the class is
1097 * non-serializable or does not define readResolve.
1098 */
1099 Object invokeReadResolve(Object obj)
1100 throws IOException, UnsupportedOperationException
1101 {
1102 if (readResolveMethod != null) {
1103 try {
1104 return readResolveMethod.invoke(obj, (Object[]) null);
1105 } catch (InvocationTargetException ex) {
1106 Throwable th = ex.getTargetException();
1107 if (th instanceof ObjectStreamException) {
1108 throw (ObjectStreamException) th;
1109 } else {
1110 throwMiscException(th);
1111 throw new InternalError(th); // never reached
1112 }
1113 } catch (IllegalAccessException ex) {
1114 // should not occur, as access checks have been suppressed
1115 throw new InternalError(ex);
1116 }
1117 } else {
1118 throw new UnsupportedOperationException();
1119 }
1120 }
1121
1122 /**
1123 * Class representing the portion of an object's serialized form allotted
1124 * to data described by a given class descriptor. If "hasData" is false,
1125 * the object's serialized form does not contain data associated with the
1126 * class descriptor.
1127 */
1128 static class ClassDataSlot {
1129
1130 /** class descriptor "occupying" this slot */
1131 final ObjectStreamClass desc;
1132 /** true if serialized form includes data for this slot's descriptor */
1133 final boolean hasData;
1134
1135 ClassDataSlot(ObjectStreamClass desc, boolean hasData) {
1136 this.desc = desc;
1137 this.hasData = hasData;
1138 }
1139 }
1140
1141 /**
1142 * Returns array of ClassDataSlot instances representing the data layout
1143 * (including superclass data) for serialized objects described by this
1144 * class descriptor. ClassDataSlots are ordered by inheritance with those
1145 * containing "higher" superclasses appearing first. The final
1146 * ClassDataSlot contains a reference to this descriptor.
1147 */
1148 ClassDataSlot[] getClassDataLayout() throws InvalidClassException {
1149 // REMIND: synchronize instead of relying on volatile?
1150 if (dataLayout == null) {
1151 dataLayout = getClassDataLayout0();
1152 }
1153 return dataLayout;
1154 }
1155
1156 private ClassDataSlot[] getClassDataLayout0()
1157 throws InvalidClassException
1158 {
1159 ArrayList<ClassDataSlot> slots = new ArrayList<>();
1160 Class<?> start = cl, end = cl;
1161
1162 // locate closest non-serializable superclass
1163 while (end != null && Serializable.class.isAssignableFrom(end)) {
1164 end = end.getSuperclass();
1165 }
1166
1167 HashSet<String> oscNames = new HashSet<>(3);
1168
1169 for (ObjectStreamClass d = this; d != null; d = d.superDesc) {
1170 if (oscNames.contains(d.name)) {
1171 throw new InvalidClassException("Circular reference.");
1172 } else {
1173 oscNames.add(d.name);
1174 }
1175
1176 // search up inheritance hierarchy for class with matching name
1177 String searchName = (d.cl != null) ? d.cl.getName() : d.name;
1178 Class<?> match = null;
1179 for (Class<?> c = start; c != end; c = c.getSuperclass()) {
1180 if (searchName.equals(c.getName())) {
1181 match = c;
1182 break;
1183 }
1184 }
1185
1186 // add "no data" slot for each unmatched class below match
1187 if (match != null) {
1188 for (Class<?> c = start; c != match; c = c.getSuperclass()) {
1189 slots.add(new ClassDataSlot(
1190 ObjectStreamClass.lookup(c, true), false));
1191 }
1192 start = match.getSuperclass();
1193 }
1194
1195 // record descriptor/class pairing
1196 slots.add(new ClassDataSlot(d.getVariantFor(match), true));
1197 }
1198
1199 // add "no data" slot for any leftover unmatched classes
1200 for (Class<?> c = start; c != end; c = c.getSuperclass()) {
1201 slots.add(new ClassDataSlot(
1202 ObjectStreamClass.lookup(c, true), false));
1203 }
1204
1205 // order slots from superclass -> subclass
1206 Collections.reverse(slots);
1207 return slots.toArray(new ClassDataSlot[slots.size()]);
1208 }
1209
1210 /**
1211 * Returns aggregate size (in bytes) of marshalled primitive field values
1212 * for represented class.
1213 */
1214 int getPrimDataSize() {
1215 return primDataSize;
1216 }
1217
1218 /**
1219 * Returns number of non-primitive serializable fields of represented
1220 * class.
1221 */
1222 int getNumObjFields() {
1223 return numObjFields;
1224 }
1225
1226 /**
1227 * Fetches the serializable primitive field values of object obj and
1228 * marshals them into byte array buf starting at offset 0. It is the
1229 * responsibility of the caller to ensure that obj is of the proper type if
1230 * non-null.
1231 */
1232 void getPrimFieldValues(Object obj, byte[] buf) {
1233 fieldRefl.getPrimFieldValues(obj, buf);
1234 }
1235
1236 /**
1237 * Sets the serializable primitive fields of object obj using values
1238 * unmarshalled from byte array buf starting at offset 0. It is the
1239 * responsibility of the caller to ensure that obj is of the proper type if
1240 * non-null.
1241 */
1242 void setPrimFieldValues(Object obj, byte[] buf) {
1243 fieldRefl.setPrimFieldValues(obj, buf);
1244 }
1245
1246 /**
1247 * Fetches the serializable object field values of object obj and stores
1248 * them in array vals starting at offset 0. It is the responsibility of
1249 * the caller to ensure that obj is of the proper type if non-null.
1250 */
1251 void getObjFieldValues(Object obj, Object[] vals) {
1252 fieldRefl.getObjFieldValues(obj, vals);
1253 }
1254
1255 /**
1256 * Sets the serializable object fields of object obj using values from
1257 * array vals starting at offset 0. It is the responsibility of the caller
1258 * to ensure that obj is of the proper type if non-null.
1259 */
1260 void setObjFieldValues(Object obj, Object[] vals) {
1261 fieldRefl.setObjFieldValues(obj, vals);
1262 }
1263
1264 /**
1265 * Calculates and sets serializable field offsets, as well as primitive
1266 * data size and object field count totals. Throws InvalidClassException
1267 * if fields are illegally ordered.
1268 */
1269 private void computeFieldOffsets() throws InvalidClassException {
1270 primDataSize = 0;
1271 numObjFields = 0;
1272 int firstObjIndex = -1;
1273
1274 for (int i = 0; i < fields.length; i++) {
1275 ObjectStreamField f = fields[i];
1276 switch (f.getTypeCode()) {
1277 case 'Z':
1278 case 'B':
1279 f.setOffset(primDataSize++);
1280 break;
1281
1282 case 'C':
1283 case 'S':
1284 f.setOffset(primDataSize);
1285 primDataSize += 2;
1286 break;
1287
1288 case 'I':
1289 case 'F':
1290 f.setOffset(primDataSize);
1291 primDataSize += 4;
1292 break;
1293
1294 case 'J':
1295 case 'D':
1296 f.setOffset(primDataSize);
1297 primDataSize += 8;
1298 break;
1299
1300 case '[':
1301 case 'L':
1302 f.setOffset(numObjFields++);
1303 if (firstObjIndex == -1) {
1304 firstObjIndex = i;
1305 }
1306 break;
1307
1308 default:
1309 throw new InternalError();
1310 }
1311 }
1312 if (firstObjIndex != -1 &&
1313 firstObjIndex + numObjFields != fields.length)
1314 {
1315 throw new InvalidClassException(name, "illegal field order");
1316 }
1317 }
1318
1319 /**
1320 * If given class is the same as the class associated with this class
1321 * descriptor, returns reference to this class descriptor. Otherwise,
1322 * returns variant of this class descriptor bound to given class.
1323 */
1324 private ObjectStreamClass getVariantFor(Class<?> cl)
1325 throws InvalidClassException
1326 {
1327 if (this.cl == cl) {
1328 return this;
1329 }
1330 ObjectStreamClass desc = new ObjectStreamClass();
1331 if (isProxy) {
1332 desc.initProxy(cl, null, superDesc);
1333 } else {
1334 desc.initNonProxy(this, cl, null, superDesc);
1335 }
1336 return desc;
1337 }
1338
1339 /**
1340 * Returns public no-arg constructor of given class, or null if none found.
1341 * Access checks are disabled on the returned constructor (if any), since
1342 * the defining class may still be non-public.
1343 */
1344 private static Constructor<?> getExternalizableConstructor(Class<?> cl) {
1345 try {
1346 Constructor<?> cons = cl.getDeclaredConstructor((Class<?>[]) null);
1347 cons.setAccessible(true);
1348 return ((cons.getModifiers() & Modifier.PUBLIC) != 0) ?
1349 cons : null;
1350 } catch (NoSuchMethodException ex) {
1351 return null;
1352 }
1353 }
1354
1355 /**
1356 * Returns subclass-accessible no-arg constructor of first non-serializable
1357 * superclass, or null if none found. Access checks are disabled on the
1358 * returned constructor (if any).
1359 */
1360 private static Constructor<?> getSerializableConstructor(Class<?> cl) {
1361 Class<?> initCl = cl;
1362 while (Serializable.class.isAssignableFrom(initCl)) {
1363 if ((initCl = initCl.getSuperclass()) == null) {
1364 return null;
1365 }
1366 }
1367 try {
1368 Constructor<?> cons = initCl.getDeclaredConstructor((Class<?>[]) null);
1369 int mods = cons.getModifiers();
1370 if ((mods & Modifier.PRIVATE) != 0 ||
1371 ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) == 0 &&
1372 !packageEquals(cl, initCl)))
1373 {
1374 return null;
1375 }
1376 cons = reflFactory.newConstructorForSerialization(cl, cons);
1377 cons.setAccessible(true);
1378 return cons;
1379 } catch (NoSuchMethodException ex) {
1380 return null;
1381 }
1382 }
1383
1384 /**
1385 * Returns non-static, non-abstract method with given signature provided it
1386 * is defined by or accessible (via inheritance) by the given class, or
1387 * null if no match found. Access checks are disabled on the returned
1388 * method (if any).
1389 */
1390 private static Method getInheritableMethod(Class<?> cl, String name,
1391 Class<?>[] argTypes,
1392 Class<?> returnType)
1393 {
1394 Method meth = null;
1395 Class<?> defCl = cl;
1396 while (defCl != null) {
1397 try {
1398 meth = defCl.getDeclaredMethod(name, argTypes);
1399 break;
1400 } catch (NoSuchMethodException ex) {
1401 defCl = defCl.getSuperclass();
1402 }
1403 }
1404
1405 if ((meth == null) || (meth.getReturnType() != returnType)) {
1406 return null;
1407 }
1408 meth.setAccessible(true);
1409 int mods = meth.getModifiers();
1410 if ((mods & (Modifier.STATIC | Modifier.ABSTRACT)) != 0) {
1411 return null;
1412 } else if ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) != 0) {
1413 return meth;
1414 } else if ((mods & Modifier.PRIVATE) != 0) {
1415 return (cl == defCl) ? meth : null;
1416 } else {
1417 return packageEquals(cl, defCl) ? meth : null;
1418 }
1419 }
1420
1421 /**
1422 * Returns non-static private method with given signature defined by given
1423 * class, or null if none found. Access checks are disabled on the
1424 * returned method (if any).
1425 */
1426 private static Method getPrivateMethod(Class<?> cl, String name,
1427 Class<?>[] argTypes,
1428 Class<?> returnType)
1429 {
1430 try {
1431 Method meth = cl.getDeclaredMethod(name, argTypes);
1432 meth.setAccessible(true);
1433 int mods = meth.getModifiers();
1434 return ((meth.getReturnType() == returnType) &&
1435 ((mods & Modifier.STATIC) == 0) &&
1436 ((mods & Modifier.PRIVATE) != 0)) ? meth : null;
1437 } catch (NoSuchMethodException ex) {
1438 return null;
1439 }
1440 }
1441
1442 /**
1443 * Returns true if classes are defined in the same runtime package, false
1444 * otherwise.
1445 */
1446 private static boolean packageEquals(Class<?> cl1, Class<?> cl2) {
1447 return (cl1.getClassLoader() == cl2.getClassLoader() &&
1448 getPackageName(cl1).equals(getPackageName(cl2)));
1449 }
1450
1451 /**
1452 * Returns package name of given class.
1453 */
1454 private static String getPackageName(Class<?> cl) {
1455 String s = cl.getName();
1456 int i = s.lastIndexOf('[');
1457 if (i >= 0) {
1458 s = s.substring(i + 2);
1459 }
1460 i = s.lastIndexOf('.');
1461 return (i >= 0) ? s.substring(0, i) : "";
1462 }
1463
1464 /**
1465 * Compares class names for equality, ignoring package names. Returns true
1466 * if class names equal, false otherwise.
1467 */
1468 private static boolean classNamesEqual(String name1, String name2) {
1469 name1 = name1.substring(name1.lastIndexOf('.') + 1);
1470 name2 = name2.substring(name2.lastIndexOf('.') + 1);
1471 return name1.equals(name2);
1472 }
1473
1474 /**
1475 * Returns JVM type signature for given primitive.
1476 */
1477 private static String getPrimitiveSignature(Class<?> cl) {
1478 if (cl == Integer.TYPE)
1479 return "I";
1480 else if (cl == Byte.TYPE)
1481 return "B";
1482 else if (cl == Long.TYPE)
1483 return "J";
1484 else if (cl == Float.TYPE)
1485 return "F";
1486 else if (cl == Double.TYPE)
1487 return "D";
1488 else if (cl == Short.TYPE)
1489 return "S";
1490 else if (cl == Character.TYPE)
1491 return "C";
1492 else if (cl == Boolean.TYPE)
1493 return "Z";
1494 else if (cl == Void.TYPE)
1495 return "V";
1496 else
1497 throw new InternalError();
1498 }
1499
1500 /**
1501 * Returns JVM type signature for given class.
1502 */
1503 static String getClassSignature(Class<?> cl) {
1504 if (cl.isPrimitive())
1505 return getPrimitiveSignature(cl);
1506 else
1507 return appendClassSignature(new StringBuilder(), cl).toString();
1508 }
1509
1510 private static StringBuilder appendClassSignature(StringBuilder sbuf, Class<?> cl) {
1511 while (cl.isArray()) {
1512 sbuf.append('[');
1513 cl = cl.getComponentType();
1514 }
1515
1516 if (cl.isPrimitive())
1517 sbuf.append(getPrimitiveSignature(cl));
1518 else
1519 sbuf.append('L').append(cl.getName().replace('.', '/')).append(';');
1520
1521 return sbuf;
1522 }
1523
1524 /**
1525 * Returns JVM type signature for given list of parameters and return type.
1526 */
1527 private static String getMethodSignature(Class<?>[] paramTypes,
1528 Class<?> retType)
1529 {
1530 StringBuilder sbuf = new StringBuilder();
1531 sbuf.append('(');
1532 for (int i = 0; i < paramTypes.length; i++) {
1533 appendClassSignature(sbuf, paramTypes[i]);
1534 }
1535 sbuf.append(')');
1536 appendClassSignature(sbuf, retType);
1537 return sbuf.toString();
1538 }
1539
1540 /**
1541 * Convenience method for throwing an exception that is either a
1542 * RuntimeException, Error, or of some unexpected type (in which case it is
1543 * wrapped inside an IOException).
1544 */
1545 private static void throwMiscException(Throwable th) throws IOException {
1546 if (th instanceof RuntimeException) {
1547 throw (RuntimeException) th;
1548 } else if (th instanceof Error) {
1549 throw (Error) th;
1550 } else {
1551 IOException ex = new IOException("unexpected exception type");
1552 ex.initCause(th);
1553 throw ex;
1554 }
1555 }
1556
1557 /**
1558 * Returns ObjectStreamField array describing the serializable fields of
1559 * the given class. Serializable fields backed by an actual field of the
1560 * class are represented by ObjectStreamFields with corresponding non-null
1561 * Field objects. Throws InvalidClassException if the (explicitly
1562 * declared) serializable fields are invalid.
1563 */
1564 private static ObjectStreamField[] getSerialFields(Class<?> cl)
1565 throws InvalidClassException
1566 {
1567 ObjectStreamField[] fields;
1568 if (Serializable.class.isAssignableFrom(cl) &&
1569 !Externalizable.class.isAssignableFrom(cl) &&
1570 !Proxy.isProxyClass(cl) &&
1571 !cl.isInterface())
1572 {
1573 if ((fields = getDeclaredSerialFields(cl)) == null) {
1574 fields = getDefaultSerialFields(cl);
1575 }
1576 Arrays.sort(fields);
1577 } else {
1578 fields = NO_FIELDS;
1579 }
1580 return fields;
1581 }
1582
1583 /**
1584 * Returns serializable fields of given class as defined explicitly by a
1585 * "serialPersistentFields" field, or null if no appropriate
1586 * "serialPersistentFields" field is defined. Serializable fields backed
1587 * by an actual field of the class are represented by ObjectStreamFields
1588 * with corresponding non-null Field objects. For compatibility with past
1589 * releases, a "serialPersistentFields" field with a null value is
1590 * considered equivalent to not declaring "serialPersistentFields". Throws
1591 * InvalidClassException if the declared serializable fields are
1592 * invalid--e.g., if multiple fields share the same name.
1593 */
1594 private static ObjectStreamField[] getDeclaredSerialFields(Class<?> cl)
1595 throws InvalidClassException
1596 {
1597 ObjectStreamField[] serialPersistentFields = null;
1598 try {
1599 Field f = cl.getDeclaredField("serialPersistentFields");
1600 int mask = Modifier.PRIVATE | Modifier.STATIC | Modifier.FINAL;
1601 if ((f.getModifiers() & mask) == mask) {
1602 f.setAccessible(true);
1603 serialPersistentFields = (ObjectStreamField[]) f.get(null);
1604 }
1605 } catch (Exception ex) {
1606 }
1607 if (serialPersistentFields == null) {
1608 return null;
1609 } else if (serialPersistentFields.length == 0) {
1610 return NO_FIELDS;
1611 }
1612
1613 ObjectStreamField[] boundFields =
1614 new ObjectStreamField[serialPersistentFields.length];
1615 Set<String> fieldNames = new HashSet<>(serialPersistentFields.length);
1616
1617 for (int i = 0; i < serialPersistentFields.length; i++) {
1618 ObjectStreamField spf = serialPersistentFields[i];
1619
1620 String fname = spf.getName();
1621 if (fieldNames.contains(fname)) {
1622 throw new InvalidClassException(
1623 "multiple serializable fields named " + fname);
1624 }
1625 fieldNames.add(fname);
1626
1627 try {
1628 Field f = cl.getDeclaredField(fname);
1629 if ((f.getType() == spf.getType()) &&
1630 ((f.getModifiers() & Modifier.STATIC) == 0))
1631 {
1632 boundFields[i] =
1633 new ObjectStreamField(f, spf.isUnshared(), true);
1634 }
1635 } catch (NoSuchFieldException ex) {
1636 }
1637 if (boundFields[i] == null) {
1638 boundFields[i] = new ObjectStreamField(
1639 fname, spf.getType(), spf.isUnshared());
1640 }
1641 }
1642 return boundFields;
1643 }
1644
1645 /**
1646 * Returns array of ObjectStreamFields corresponding to all non-static
1647 * non-transient fields declared by given class. Each ObjectStreamField
1648 * contains a Field object for the field it represents. If no default
1649 * serializable fields exist, NO_FIELDS is returned.
1650 */
1651 private static ObjectStreamField[] getDefaultSerialFields(Class<?> cl) {
1652 Field[] clFields = cl.getDeclaredFields();
1653 ArrayList<ObjectStreamField> list = new ArrayList<>();
1654 int mask = Modifier.STATIC | Modifier.TRANSIENT;
1655
1656 for (int i = 0; i < clFields.length; i++) {
1657 if ((clFields[i].getModifiers() & mask) == 0) {
1658 list.add(new ObjectStreamField(clFields[i], false, true));
1659 }
1660 }
1661 int size = list.size();
1662 return (size == 0) ? NO_FIELDS :
1663 list.toArray(new ObjectStreamField[size]);
1664 }
1665
1666 /**
1667 * Returns explicit serial version UID value declared by given class, or
1668 * null if none.
1669 */
1670 private static Long getDeclaredSUID(Class<?> cl) {
1671 try {
1672 Field f = cl.getDeclaredField("serialVersionUID");
1673 int mask = Modifier.STATIC | Modifier.FINAL;
1674 if ((f.getModifiers() & mask) == mask) {
1675 f.setAccessible(true);
1676 return Long.valueOf(f.getLong(null));
1677 }
1678 } catch (Exception ex) {
1679 }
1680 return null;
1681 }
1682
1683 /**
1684 * Computes the default serial version UID value for the given class.
1685 */
1686 private static long computeDefaultSUID(Class<?> cl) {
1687 if (!Serializable.class.isAssignableFrom(cl) || Proxy.isProxyClass(cl))
1688 {
1689 return 0L;
1690 }
1691
1692 try {
1693 ByteArrayOutputStream bout = new ByteArrayOutputStream();
1694 DataOutputStream dout = new DataOutputStream(bout);
1695
1696 dout.writeUTF(cl.getName());
1697
1698 int classMods = cl.getModifiers() &
1699 (Modifier.PUBLIC | Modifier.FINAL |
1700 Modifier.INTERFACE | Modifier.ABSTRACT);
1701
1702 /*
1703 * compensate for javac bug in which ABSTRACT bit was set for an
1704 * interface only if the interface declared methods
1705 */
1706 Method[] methods = cl.getDeclaredMethods();
1707 if ((classMods & Modifier.INTERFACE) != 0) {
1708 classMods = (methods.length > 0) ?
1709 (classMods | Modifier.ABSTRACT) :
1710 (classMods & ~Modifier.ABSTRACT);
1711 }
1712 dout.writeInt(classMods);
1713
1714 if (!cl.isArray()) {
1715 /*
1716 * compensate for change in 1.2FCS in which
1717 * Class.getInterfaces() was modified to return Cloneable and
1718 * Serializable for array classes.
1719 */
1720 Class<?>[] interfaces = cl.getInterfaces();
1721 String[] ifaceNames = new String[interfaces.length];
1722 for (int i = 0; i < interfaces.length; i++) {
1723 ifaceNames[i] = interfaces[i].getName();
1724 }
1725 Arrays.sort(ifaceNames);
1726 for (int i = 0; i < ifaceNames.length; i++) {
1727 dout.writeUTF(ifaceNames[i]);
1728 }
1729 }
1730
1731 Field[] fields = cl.getDeclaredFields();
1732 MemberSignature[] fieldSigs = new MemberSignature[fields.length];
1733 for (int i = 0; i < fields.length; i++) {
1734 fieldSigs[i] = new MemberSignature(fields[i]);
1735 }
1736 Arrays.sort(fieldSigs, new Comparator<MemberSignature>() {
1737 public int compare(MemberSignature ms1, MemberSignature ms2) {
1738 return ms1.name.compareTo(ms2.name);
1739 }
1740 });
1741 for (int i = 0; i < fieldSigs.length; i++) {
1742 MemberSignature sig = fieldSigs[i];
1743 int mods = sig.member.getModifiers() &
1744 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1745 Modifier.STATIC | Modifier.FINAL | Modifier.VOLATILE |
1746 Modifier.TRANSIENT);
1747 if (((mods & Modifier.PRIVATE) == 0) ||
1748 ((mods & (Modifier.STATIC | Modifier.TRANSIENT)) == 0))
1749 {
1750 dout.writeUTF(sig.name);
1751 dout.writeInt(mods);
1752 dout.writeUTF(sig.signature);
1753 }
1754 }
1755
1756 if (hasStaticInitializer(cl)) {
1757 dout.writeUTF("<clinit>");
1758 dout.writeInt(Modifier.STATIC);
1759 dout.writeUTF("()V");
1760 }
1761
1762 Constructor<?>[] cons = cl.getDeclaredConstructors();
1763 MemberSignature[] consSigs = new MemberSignature[cons.length];
1764 for (int i = 0; i < cons.length; i++) {
1765 consSigs[i] = new MemberSignature(cons[i]);
1766 }
1767 Arrays.sort(consSigs, new Comparator<MemberSignature>() {
1768 public int compare(MemberSignature ms1, MemberSignature ms2) {
1769 return ms1.signature.compareTo(ms2.signature);
1770 }
1771 });
1772 for (int i = 0; i < consSigs.length; i++) {
1773 MemberSignature sig = consSigs[i];
1774 int mods = sig.member.getModifiers() &
1775 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1776 Modifier.STATIC | Modifier.FINAL |
1777 Modifier.SYNCHRONIZED | Modifier.NATIVE |
1778 Modifier.ABSTRACT | Modifier.STRICT);
1779 if ((mods & Modifier.PRIVATE) == 0) {
1780 dout.writeUTF("<init>");
1781 dout.writeInt(mods);
1782 dout.writeUTF(sig.signature.replace('/', '.'));
1783 }
1784 }
1785
1786 MemberSignature[] methSigs = new MemberSignature[methods.length];
1787 for (int i = 0; i < methods.length; i++) {
1788 methSigs[i] = new MemberSignature(methods[i]);
1789 }
1790 Arrays.sort(methSigs, new Comparator<MemberSignature>() {
1791 public int compare(MemberSignature ms1, MemberSignature ms2) {
1792 int comp = ms1.name.compareTo(ms2.name);
1793 if (comp == 0) {
1794 comp = ms1.signature.compareTo(ms2.signature);
1795 }
1796 return comp;
1797 }
1798 });
1799 for (int i = 0; i < methSigs.length; i++) {
1800 MemberSignature sig = methSigs[i];
1801 int mods = sig.member.getModifiers() &
1802 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1803 Modifier.STATIC | Modifier.FINAL |
1804 Modifier.SYNCHRONIZED | Modifier.NATIVE |
1805 Modifier.ABSTRACT | Modifier.STRICT);
1806 if ((mods & Modifier.PRIVATE) == 0) {
1807 dout.writeUTF(sig.name);
1808 dout.writeInt(mods);
1809 dout.writeUTF(sig.signature.replace('/', '.'));
1810 }
1811 }
1812
1813 dout.flush();
1814
1815 MessageDigest md = MessageDigest.getInstance("SHA");
1816 byte[] hashBytes = md.digest(bout.toByteArray());
1817 long hash = 0;
1818 for (int i = Math.min(hashBytes.length, 8) - 1; i >= 0; i--) {
1819 hash = (hash << 8) | (hashBytes[i] & 0xFF);
1820 }
1821 return hash;
1822 } catch (IOException ex) {
1823 throw new InternalError(ex);
1824 } catch (NoSuchAlgorithmException ex) {
1825 throw new SecurityException(ex.getMessage());
1826 }
1827 }
1828
1829 /**
1830 * Returns true if the given class defines a static initializer method,
1831 * false otherwise.
1832 */
1833 private native static boolean hasStaticInitializer(Class<?> cl);
1834
1835 /**
1836 * Class for computing and caching field/constructor/method signatures
1837 * during serialVersionUID calculation.
1838 */
1839 private static class MemberSignature {
1840
1841 public final Member member;
1842 public final String name;
1843 public final String signature;
1844
1845 public MemberSignature(Field field) {
1846 member = field;
1847 name = field.getName();
1848 signature = getClassSignature(field.getType());
1849 }
1850
1851 public MemberSignature(Constructor<?> cons) {
1852 member = cons;
1853 name = cons.getName();
1854 signature = getMethodSignature(
1855 cons.getParameterTypes(), Void.TYPE);
1856 }
1857
1858 public MemberSignature(Method meth) {
1859 member = meth;
1860 name = meth.getName();
1861 signature = getMethodSignature(
1862 meth.getParameterTypes(), meth.getReturnType());
1863 }
1864 }
1865
1866 /**
1867 * Class for setting and retrieving serializable field values in batch.
1868 */
1869 // REMIND: dynamically generate these?
1870 private static class FieldReflector {
1871
1872 /** handle for performing unsafe operations */
1873 private static final Unsafe unsafe = Unsafe.getUnsafe();
1874
1875 /** fields to operate on */
1876 private final ObjectStreamField[] fields;
1877 /** number of primitive fields */
1878 private final int numPrimFields;
1879 /** unsafe field keys for reading fields - may contain dupes */
1880 private final long[] readKeys;
1881 /** unsafe fields keys for writing fields - no dupes */
1882 private final long[] writeKeys;
1883 /** field data offsets */
1884 private final int[] offsets;
1885 /** field type codes */
1886 private final char[] typeCodes;
1887 /** field types */
1888 private final Class<?>[] types;
1889
1890 /**
1891 * Constructs FieldReflector capable of setting/getting values from the
1892 * subset of fields whose ObjectStreamFields contain non-null
1893 * reflective Field objects. ObjectStreamFields with null Fields are
1894 * treated as filler, for which get operations return default values
1895 * and set operations discard given values.
1896 */
1897 FieldReflector(ObjectStreamField[] fields) {
1898 this.fields = fields;
1899 int nfields = fields.length;
1900 readKeys = new long[nfields];
1901 writeKeys = new long[nfields];
1902 offsets = new int[nfields];
1903 typeCodes = new char[nfields];
1904 ArrayList<Class<?>> typeList = new ArrayList<>();
1905 Set<Long> usedKeys = new HashSet<>();
1906
1907
1908 for (int i = 0; i < nfields; i++) {
1909 ObjectStreamField f = fields[i];
1910 Field rf = f.getField();
1911 long key = (rf != null) ?
1912 unsafe.objectFieldOffset(rf) : Unsafe.INVALID_FIELD_OFFSET;
1913 readKeys[i] = key;
1914 writeKeys[i] = usedKeys.add(key) ?
1915 key : Unsafe.INVALID_FIELD_OFFSET;
1916 offsets[i] = f.getOffset();
1917 typeCodes[i] = f.getTypeCode();
1918 if (!f.isPrimitive()) {
1919 typeList.add((rf != null) ? rf.getType() : null);
1920 }
1921 }
1922
1923 types = typeList.toArray(new Class<?>[typeList.size()]);
1924 numPrimFields = nfields - types.length;
1925 }
1926
1927 /**
1928 * Returns list of ObjectStreamFields representing fields operated on
1929 * by this reflector. The shared/unshared values and Field objects
1930 * contained by ObjectStreamFields in the list reflect their bindings
1931 * to locally defined serializable fields.
1932 */
1933 ObjectStreamField[] getFields() {
1934 return fields;
1935 }
1936
1937 /**
1938 * Fetches the serializable primitive field values of object obj and
1939 * marshals them into byte array buf starting at offset 0. The caller
1940 * is responsible for ensuring that obj is of the proper type.
1941 */
1942 void getPrimFieldValues(Object obj, byte[] buf) {
1943 if (obj == null) {
1944 throw new NullPointerException();
1945 }
1946 /* assuming checkDefaultSerialize() has been called on the class
1947 * descriptor this FieldReflector was obtained from, no field keys
1948 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET.
1949 */
1950 for (int i = 0; i < numPrimFields; i++) {
1951 long key = readKeys[i];
1952 int off = offsets[i];
1953 switch (typeCodes[i]) {
1954 case 'Z':
1955 Bits.putBoolean(buf, off, unsafe.getBoolean(obj, key));
1956 break;
1957
1958 case 'B':
1959 buf[off] = unsafe.getByte(obj, key);
1960 break;
1961
1962 case 'C':
1963 Bits.putChar(buf, off, unsafe.getChar(obj, key));
1964 break;
1965
1966 case 'S':
1967 Bits.putShort(buf, off, unsafe.getShort(obj, key));
1968 break;
1969
1970 case 'I':
1971 Bits.putInt(buf, off, unsafe.getInt(obj, key));
1972 break;
1973
1974 case 'F':
1975 Bits.putFloat(buf, off, unsafe.getFloat(obj, key));
1976 break;
1977
1978 case 'J':
1979 Bits.putLong(buf, off, unsafe.getLong(obj, key));
1980 break;
1981
1982 case 'D':
1983 Bits.putDouble(buf, off, unsafe.getDouble(obj, key));
1984 break;
1985
1986 default:
1987 throw new InternalError();
1988 }
1989 }
1990 }
1991
1992 /**
1993 * Sets the serializable primitive fields of object obj using values
1994 * unmarshalled from byte array buf starting at offset 0. The caller
1995 * is responsible for ensuring that obj is of the proper type.
1996 */
1997 void setPrimFieldValues(Object obj, byte[] buf) {
1998 if (obj == null) {
1999 throw new NullPointerException();
2000 }
2001 for (int i = 0; i < numPrimFields; i++) {
2002 long key = writeKeys[i];
2003 if (key == Unsafe.INVALID_FIELD_OFFSET) {
2004 continue; // discard value
2005 }
2006 int off = offsets[i];
2007 switch (typeCodes[i]) {
2008 case 'Z':
2009 unsafe.putBoolean(obj, key, Bits.getBoolean(buf, off));
2010 break;
2011
2012 case 'B':
2013 unsafe.putByte(obj, key, buf[off]);
2014 break;
2015
2016 case 'C':
2017 unsafe.putChar(obj, key, Bits.getChar(buf, off));
2018 break;
2019
2020 case 'S':
2021 unsafe.putShort(obj, key, Bits.getShort(buf, off));
2022 break;
2023
2024 case 'I':
2025 unsafe.putInt(obj, key, Bits.getInt(buf, off));
2026 break;
2027
2028 case 'F':
2029 unsafe.putFloat(obj, key, Bits.getFloat(buf, off));
2030 break;
2031
2032 case 'J':
2033 unsafe.putLong(obj, key, Bits.getLong(buf, off));
2034 break;
2035
2036 case 'D':
2037 unsafe.putDouble(obj, key, Bits.getDouble(buf, off));
2038 break;
2039
2040 default:
2041 throw new InternalError();
2042 }
2043 }
2044 }
2045
2046 /**
2047 * Fetches the serializable object field values of object obj and
2048 * stores them in array vals starting at offset 0. The caller is
2049 * responsible for ensuring that obj is of the proper type.
2050 */
2051 void getObjFieldValues(Object obj, Object[] vals) {
2052 if (obj == null) {
2053 throw new NullPointerException();
2054 }
2055 /* assuming checkDefaultSerialize() has been called on the class
2056 * descriptor this FieldReflector was obtained from, no field keys
2057 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET.
2058 */
2059 for (int i = numPrimFields; i < fields.length; i++) {
2060 switch (typeCodes[i]) {
2061 case 'L':
2062 case '[':
2063 vals[offsets[i]] = unsafe.getObject(obj, readKeys[i]);
2064 break;
2065
2066 default:
2067 throw new InternalError();
2068 }
2069 }
2070 }
2071
2072 /**
2073 * Sets the serializable object fields of object obj using values from
2074 * array vals starting at offset 0. The caller is responsible for
2075 * ensuring that obj is of the proper type; however, attempts to set a
2076 * field with a value of the wrong type will trigger an appropriate
2077 * ClassCastException.
2078 */
2079 void setObjFieldValues(Object obj, Object[] vals) {
2080 if (obj == null) {
2081 throw new NullPointerException();
2082 }
2083 for (int i = numPrimFields; i < fields.length; i++) {
2084 long key = writeKeys[i];
2085 if (key == Unsafe.INVALID_FIELD_OFFSET) {
2086 continue; // discard value
2087 }
2088 switch (typeCodes[i]) {
2089 case 'L':
2090 case '[':
2091 Object val = vals[offsets[i]];
2092 if (val != null &&
2093 !types[i - numPrimFields].isInstance(val))
2094 {
2095 Field f = fields[i].getField();
2096 throw new ClassCastException(
2097 "cannot assign instance of " +
2098 val.getClass().getName() + " to field " +
2099 f.getDeclaringClass().getName() + "." +
2100 f.getName() + " of type " +
2101 f.getType().getName() + " in instance of " +
2102 obj.getClass().getName());
2103 }
2104 unsafe.putObject(obj, key, val);
2105 break;
2106
2107 default:
2108 throw new InternalError();
2109 }
2110 }
2111 }
2112 }
2113
2114 /**
2115 * Matches given set of serializable fields with serializable fields
2116 * described by the given local class descriptor, and returns a
2117 * FieldReflector instance capable of setting/getting values from the
2118 * subset of fields that match (non-matching fields are treated as filler,
2119 * for which get operations return default values and set operations
2120 * discard given values). Throws InvalidClassException if unresolvable
2121 * type conflicts exist between the two sets of fields.
2122 */
2123 private static FieldReflector getReflector(ObjectStreamField[] fields,
2124 ObjectStreamClass localDesc)
2125 throws InvalidClassException
2126 {
2127 // class irrelevant if no fields
2128 Class<?> cl = (localDesc != null && fields.length > 0) ?
2129 localDesc.cl : null;
2130 processQueue(Caches.reflectorsQueue, Caches.reflectors);
2131 FieldReflectorKey key = new FieldReflectorKey(cl, fields,
2132 Caches.reflectorsQueue);
2133 Reference<?> ref = Caches.reflectors.get(key);
2134 Object entry = null;
2135 if (ref != null) {
2136 entry = ref.get();
2137 }
2138 EntryFuture future = null;
2139 if (entry == null) {
2140 EntryFuture newEntry = new EntryFuture();
2141 Reference<?> newRef = new SoftReference<>(newEntry);
2142 do {
2143 if (ref != null) {
2144 Caches.reflectors.remove(key, ref);
2145 }
2146 ref = Caches.reflectors.putIfAbsent(key, newRef);
2147 if (ref != null) {
2148 entry = ref.get();
2149 }
2150 } while (ref != null && entry == null);
2151 if (entry == null) {
2152 future = newEntry;
2153 }
2154 }
2155
2156 if (entry instanceof FieldReflector) { // check common case first
2157 return (FieldReflector) entry;
2158 } else if (entry instanceof EntryFuture) {
2159 entry = ((EntryFuture) entry).get();
2160 } else if (entry == null) {
2161 try {
2162 entry = new FieldReflector(matchFields(fields, localDesc));
2163 } catch (Throwable th) {
2164 entry = th;
2165 }
2166 future.set(entry);
2167 Caches.reflectors.put(key, new SoftReference<Object>(entry));
2168 }
2169
2170 if (entry instanceof FieldReflector) {
2171 return (FieldReflector) entry;
2172 } else if (entry instanceof InvalidClassException) {
2173 throw (InvalidClassException) entry;
2174 } else if (entry instanceof RuntimeException) {
2175 throw (RuntimeException) entry;
2176 } else if (entry instanceof Error) {
2177 throw (Error) entry;
2178 } else {
2179 throw new InternalError("unexpected entry: " + entry);
2180 }
2181 }
2182
2183 /**
2184 * FieldReflector cache lookup key. Keys are considered equal if they
2185 * refer to the same class and equivalent field formats.
2186 */
2187 private static class FieldReflectorKey extends WeakReference<Class<?>> {
2188
2189 private final String sigs;
2190 private final int hash;
2191 private final boolean nullClass;
2192
2193 FieldReflectorKey(Class<?> cl, ObjectStreamField[] fields,
2194 ReferenceQueue<Class<?>> queue)
2195 {
2196 super(cl, queue);
2197 nullClass = (cl == null);
2198 StringBuilder sbuf = new StringBuilder();
2199 for (int i = 0; i < fields.length; i++) {
2200 ObjectStreamField f = fields[i];
2201 sbuf.append(f.getName()).append(f.getSignature());
2202 }
2203 sigs = sbuf.toString();
2204 hash = System.identityHashCode(cl) + sigs.hashCode();
2205 }
2206
2207 public int hashCode() {
2208 return hash;
2209 }
2210
2211 public boolean equals(Object obj) {
2212 if (obj == this) {
2213 return true;
2214 }
2215
2216 if (obj instanceof FieldReflectorKey) {
2217 FieldReflectorKey other = (FieldReflectorKey) obj;
2218 Class<?> referent;
2219 return (nullClass ? other.nullClass
2220 : ((referent = get()) != null) &&
2221 (referent == other.get())) &&
2222 sigs.equals(other.sigs);
2223 } else {
2224 return false;
2225 }
2226 }
2227 }
2228
2229 /**
2230 * Matches given set of serializable fields with serializable fields
2231 * obtained from the given local class descriptor (which contain bindings
2232 * to reflective Field objects). Returns list of ObjectStreamFields in
2233 * which each ObjectStreamField whose signature matches that of a local
2234 * field contains a Field object for that field; unmatched
2235 * ObjectStreamFields contain null Field objects. Shared/unshared settings
2236 * of the returned ObjectStreamFields also reflect those of matched local
2237 * ObjectStreamFields. Throws InvalidClassException if unresolvable type
2238 * conflicts exist between the two sets of fields.
2239 */
2240 private static ObjectStreamField[] matchFields(ObjectStreamField[] fields,
2241 ObjectStreamClass localDesc)
2242 throws InvalidClassException
2243 {
2244 ObjectStreamField[] localFields = (localDesc != null) ?
2245 localDesc.fields : NO_FIELDS;
2246
2247 /*
2248 * Even if fields == localFields, we cannot simply return localFields
2249 * here. In previous implementations of serialization,
2250 * ObjectStreamField.getType() returned Object.class if the
2251 * ObjectStreamField represented a non-primitive field and belonged to
2252 * a non-local class descriptor. To preserve this (questionable)
2253 * behavior, the ObjectStreamField instances returned by matchFields
2254 * cannot report non-primitive types other than Object.class; hence
2255 * localFields cannot be returned directly.
2256 */
2257
2258 ObjectStreamField[] matches = new ObjectStreamField[fields.length];
2259 for (int i = 0; i < fields.length; i++) {
2260 ObjectStreamField f = fields[i], m = null;
2261 for (int j = 0; j < localFields.length; j++) {
2262 ObjectStreamField lf = localFields[j];
2263 if (f.getName().equals(lf.getName())) {
2264 if ((f.isPrimitive() || lf.isPrimitive()) &&
2265 f.getTypeCode() != lf.getTypeCode())
2266 {
2267 throw new InvalidClassException(localDesc.name,
2268 "incompatible types for field " + f.getName());
2269 }
2270 if (lf.getField() != null) {
2271 m = new ObjectStreamField(
2272 lf.getField(), lf.isUnshared(), false);
2273 } else {
2274 m = new ObjectStreamField(
2275 lf.getName(), lf.getSignature(), lf.isUnshared());
2276 }
2277 }
2278 }
2279 if (m == null) {
2280 m = new ObjectStreamField(
2281 f.getName(), f.getSignature(), false);
2282 }
2283 m.setOffset(f.getOffset());
2284 matches[i] = m;
2285 }
2286 return matches;
2287 }
2288
2289 /**
2290 * Removes from the specified map any keys that have been enqueued
2291 * on the specified reference queue.
2292 */
2293 static void processQueue(ReferenceQueue<Class<?>> queue,
2294 ConcurrentMap<? extends
2295 WeakReference<Class<?>>, ?> map)
2296 {
2297 Reference<? extends Class<?>> ref;
2298 while((ref = queue.poll()) != null) {
2299 map.remove(ref);
2300 }
2301 }
2302
2303 /**
2304 * Weak key for Class objects.
2305 *
2306 **/
2307 static class WeakClassKey extends WeakReference<Class<?>> {
2308 /**
2309 * saved value of the referent's identity hash code, to maintain
2310 * a consistent hash code after the referent has been cleared
2311 */
2312 private final int hash;
2313
2314 /**
2315 * Create a new WeakClassKey to the given object, registered
2316 * with a queue.
2317 */
2318 WeakClassKey(Class<?> cl, ReferenceQueue<Class<?>> refQueue) {
2319 super(cl, refQueue);
2320 hash = System.identityHashCode(cl);
2321 }
2322
2323 /**
2324 * Returns the identity hash code of the original referent.
2325 */
2326 public int hashCode() {
2327 return hash;
2328 }
2329
2330 /**
2331 * Returns true if the given object is this identical
2332 * WeakClassKey instance, or, if this object's referent has not
2333 * been cleared, if the given object is another WeakClassKey
2334 * instance with the identical non-null referent as this one.
2335 */
2336 public boolean equals(Object obj) {
2337 if (obj == this) {
2338 return true;
2339 }
2340
2341 if (obj instanceof WeakClassKey) {
2342 Object referent = get();
2343 return (referent != null) &&
2344 (referent == ((WeakClassKey) obj).get());
2345 } else {
2346 return false;
2347 }
2348 }
2349 }
2350 }