1 /*
2 * Copyright (c) 1996, 2015, 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 jdk.internal.misc.Unsafe;
52 import jdk.internal.reflect.CallerSensitive;
53 import jdk.internal.reflect.Reflection;
54 import jdk.internal.reflect.ReflectionFactory;
55 import sun.reflect.misc.ReflectUtil;
56
57 import static java.io.ObjectStreamField.*;
58
59 /**
60 * Serialization's descriptor for classes. It contains the name and
61 * serialVersionUID of the class. The ObjectStreamClass for a specific class
62 * loaded in this Java VM can be found/created using the lookup method.
63 *
64 * <p>The algorithm to compute the SerialVersionUID is described in
65 * <a href="../../../platform/serialization/spec/class.html#4100">Object
66 * Serialization Specification, Section 4.6, Stream Unique Identifiers</a>.
67 *
68 * @author Mike Warres
69 * @author Roger Riggs
70 * @see ObjectStreamField
71 * @see <a href="../../../platform/serialization/spec/class.html">Object Serialization Specification, Section 4, Class Descriptors</a>
72 * @since 1.1
73 */
74 public class ObjectStreamClass implements Serializable {
75
76 /** serialPersistentFields value indicating no serializable fields */
77 public static final ObjectStreamField[] NO_FIELDS =
78 new ObjectStreamField[0];
79
80 private static final long serialVersionUID = -6120832682080437368L;
81 private static final ObjectStreamField[] serialPersistentFields =
82 NO_FIELDS;
83
84 /** reflection factory for obtaining serialization constructors */
85 private static final ReflectionFactory reflFactory =
86 AccessController.doPrivileged(
87 new ReflectionFactory.GetReflectionFactoryAction());
88
89 private static class Caches {
90 /** cache mapping local classes -> descriptors */
91 static final ConcurrentMap<WeakClassKey,Reference<?>> localDescs =
92 new ConcurrentHashMap<>();
93
94 /** cache mapping field group/local desc pairs -> field reflectors */
95 static final ConcurrentMap<FieldReflectorKey,Reference<?>> reflectors =
96 new ConcurrentHashMap<>();
97
98 /** queue for WeakReferences to local classes */
99 private static final ReferenceQueue<Class<?>> localDescsQueue =
100 new ReferenceQueue<>();
101 /** queue for WeakReferences to field reflectors keys */
102 private static final ReferenceQueue<Class<?>> reflectorsQueue =
103 new ReferenceQueue<>();
104 }
105
106 /** class associated with this descriptor (if any) */
107 private Class<?> cl;
108 /** name of class represented by this descriptor */
109 private String name;
110 /** serialVersionUID of represented class (null if not computed yet) */
111 private volatile Long suid;
112
113 /** true if represents dynamic proxy class */
114 private boolean isProxy;
115 /** true if represents enum type */
116 private boolean isEnum;
117 /** true if represented class implements Serializable */
118 private boolean serializable;
119 /** true if represented class implements Externalizable */
120 private boolean externalizable;
121 /** true if desc has data written by class-defined writeObject method */
122 private boolean hasWriteObjectData;
123 /**
124 * true if desc has externalizable data written in block data format; this
125 * must be true by default to accommodate ObjectInputStream subclasses which
126 * override readClassDescriptor() to return class descriptors obtained from
127 * ObjectStreamClass.lookup() (see 4461737)
128 */
129 private boolean hasBlockExternalData = true;
130
131 /**
132 * Contains information about InvalidClassException instances to be thrown
133 * when attempting operations on an invalid class. Note that instances of
134 * this class are immutable and are potentially shared among
135 * ObjectStreamClass instances.
136 */
137 private static class ExceptionInfo {
138 private final String className;
139 private final String message;
140
141 ExceptionInfo(String cn, String msg) {
142 className = cn;
143 message = msg;
144 }
145
146 /**
147 * Returns (does not throw) an InvalidClassException instance created
148 * from the information in this object, suitable for being thrown by
149 * the caller.
150 */
151 InvalidClassException newInvalidClassException() {
152 return new InvalidClassException(className, message);
153 }
154 }
155
156 /** exception (if any) thrown while attempting to resolve class */
157 private ClassNotFoundException resolveEx;
158 /** exception (if any) to throw if non-enum deserialization attempted */
159 private ExceptionInfo deserializeEx;
160 /** exception (if any) to throw if non-enum serialization attempted */
161 private ExceptionInfo serializeEx;
162 /** exception (if any) to throw if default serialization attempted */
163 private ExceptionInfo defaultSerializeEx;
164
165 /** serializable fields */
166 private ObjectStreamField[] fields;
167 /** aggregate marshalled size of primitive fields */
168 private int primDataSize;
169 /** number of non-primitive fields */
170 private int numObjFields;
171 /** reflector for setting/getting serializable field values */
172 private FieldReflector fieldRefl;
173 /** data layout of serialized objects described by this class desc */
174 private volatile ClassDataSlot[] dataLayout;
175
176 /** serialization-appropriate constructor, or null if none */
177 private Constructor<?> cons;
178 /** class-defined writeObject method, or null if none */
179 private Method writeObjectMethod;
180 /** class-defined readObject method, or null if none */
181 private Method readObjectMethod;
182 /** class-defined readObjectNoData method, or null if none */
183 private Method readObjectNoDataMethod;
184 /** class-defined writeReplace method, or null if none */
185 private Method writeReplaceMethod;
186 /** class-defined readResolve method, or null if none */
187 private Method readResolveMethod;
188
189 /** local class descriptor for represented class (may point to self) */
190 private ObjectStreamClass localDesc;
191 /** superclass descriptor appearing in stream */
192 private ObjectStreamClass superDesc;
193
194 /** true if, and only if, the object has been correctly initialized */
195 private boolean initialized;
196
197 /**
198 * Initializes native code.
199 */
200 private static native void initNative();
201 static {
202 initNative();
203 }
204
205 /**
206 * Find the descriptor for a class that can be serialized. Creates an
207 * ObjectStreamClass instance if one does not exist yet for class. Null is
208 * returned if the specified class does not implement java.io.Serializable
209 * or java.io.Externalizable.
210 *
211 * @param cl class for which to get the descriptor
212 * @return the class descriptor for the specified class
213 */
214 public static ObjectStreamClass lookup(Class<?> cl) {
215 return lookup(cl, false);
216 }
217
218 /**
219 * Returns the descriptor for any class, regardless of whether it
220 * implements {@link Serializable}.
221 *
222 * @param cl class for which to get the descriptor
223 * @return the class descriptor for the specified class
224 * @since 1.6
225 */
226 public static ObjectStreamClass lookupAny(Class<?> cl) {
227 return lookup(cl, true);
228 }
229
230 /**
231 * Returns the name of the class described by this descriptor.
232 * This method returns the name of the class in the format that
233 * is used by the {@link Class#getName} method.
234 *
235 * @return a string representing the name of the class
236 */
237 public String getName() {
238 return name;
239 }
240
241 /**
242 * Return the serialVersionUID for this class. The serialVersionUID
243 * defines a set of classes all with the same name that have evolved from a
244 * common root class and agree to be serialized and deserialized using a
245 * common format. NonSerializable classes have a serialVersionUID of 0L.
246 *
247 * @return the SUID of the class described by this descriptor
248 */
249 public long getSerialVersionUID() {
250 // REMIND: synchronize instead of relying on volatile?
251 if (suid == null) {
252 suid = AccessController.doPrivileged(
253 new PrivilegedAction<Long>() {
254 public Long run() {
255 return computeDefaultSUID(cl);
256 }
257 }
258 );
259 }
260 return suid.longValue();
261 }
262
263 /**
264 * Return the class in the local VM that this version is mapped to. Null
265 * is returned if there is no corresponding local class.
266 *
267 * @return the <code>Class</code> instance that this descriptor represents
268 */
269 @CallerSensitive
270 public Class<?> forClass() {
271 if (cl == null) {
272 return null;
273 }
274 requireInitialized();
275 if (System.getSecurityManager() != null) {
276 Class<?> caller = Reflection.getCallerClass();
277 if (ReflectUtil.needsPackageAccessCheck(caller.getClassLoader(), cl.getClassLoader())) {
278 ReflectUtil.checkPackageAccess(cl);
279 }
280 }
281 return cl;
282 }
283
284 /**
285 * Return an array of the fields of this serializable class.
286 *
287 * @return an array containing an element for each persistent field of
288 * this class. Returns an array of length zero if there are no
289 * fields.
290 * @since 1.2
291 */
292 public ObjectStreamField[] getFields() {
293 return getFields(true);
294 }
295
296 /**
297 * Get the field of this class by name.
298 *
299 * @param name the name of the data field to look for
300 * @return The ObjectStreamField object of the named field or null if
301 * there is no such named field.
302 */
303 public ObjectStreamField getField(String name) {
304 return getField(name, null);
305 }
306
307 /**
308 * Return a string describing this ObjectStreamClass.
309 */
310 public String toString() {
311 return name + ": static final long serialVersionUID = " +
312 getSerialVersionUID() + "L;";
313 }
314
315 /**
316 * Looks up and returns class descriptor for given class, or null if class
317 * is non-serializable and "all" is set to false.
318 *
319 * @param cl class to look up
320 * @param all if true, return descriptors for all classes; if false, only
321 * return descriptors for serializable classes
322 */
323 static ObjectStreamClass lookup(Class<?> cl, boolean all) {
324 if (!(all || Serializable.class.isAssignableFrom(cl))) {
325 return null;
326 }
327 processQueue(Caches.localDescsQueue, Caches.localDescs);
328 WeakClassKey key = new WeakClassKey(cl, Caches.localDescsQueue);
329 Reference<?> ref = Caches.localDescs.get(key);
330 Object entry = null;
331 if (ref != null) {
332 entry = ref.get();
333 }
334 EntryFuture future = null;
335 if (entry == null) {
336 EntryFuture newEntry = new EntryFuture();
337 Reference<?> newRef = new SoftReference<>(newEntry);
338 do {
339 if (ref != null) {
340 Caches.localDescs.remove(key, ref);
341 }
342 ref = Caches.localDescs.putIfAbsent(key, newRef);
343 if (ref != null) {
344 entry = ref.get();
345 }
346 } while (ref != null && entry == null);
347 if (entry == null) {
348 future = newEntry;
349 }
350 }
351
352 if (entry instanceof ObjectStreamClass) { // check common case first
353 return (ObjectStreamClass) entry;
354 }
355 if (entry instanceof EntryFuture) {
356 future = (EntryFuture) entry;
357 if (future.getOwner() == Thread.currentThread()) {
358 /*
359 * Handle nested call situation described by 4803747: waiting
360 * for future value to be set by a lookup() call further up the
361 * stack will result in deadlock, so calculate and set the
362 * future value here instead.
363 */
364 entry = null;
365 } else {
366 entry = future.get();
367 }
368 }
369 if (entry == null) {
370 try {
371 entry = new ObjectStreamClass(cl);
372 } catch (Throwable th) {
373 entry = th;
374 }
375 if (future.set(entry)) {
376 Caches.localDescs.put(key, new SoftReference<>(entry));
377 } else {
378 // nested lookup call already set future
379 entry = future.get();
380 }
381 }
382
383 if (entry instanceof ObjectStreamClass) {
384 return (ObjectStreamClass) entry;
385 } else if (entry instanceof RuntimeException) {
386 throw (RuntimeException) entry;
387 } else if (entry instanceof Error) {
388 throw (Error) entry;
389 } else {
390 throw new InternalError("unexpected entry: " + entry);
391 }
392 }
393
394 /**
395 * Placeholder used in class descriptor and field reflector lookup tables
396 * for an entry in the process of being initialized. (Internal) callers
397 * which receive an EntryFuture belonging to another thread as the result
398 * of a lookup should call the get() method of the EntryFuture; this will
399 * return the actual entry once it is ready for use and has been set(). To
400 * conserve objects, EntryFutures synchronize on themselves.
401 */
402 private static class EntryFuture {
403
404 private static final Object unset = new Object();
405 private final Thread owner = Thread.currentThread();
406 private Object entry = unset;
407
408 /**
409 * Attempts to set the value contained by this EntryFuture. If the
410 * EntryFuture's value has not been set already, then the value is
411 * saved, any callers blocked in the get() method are notified, and
412 * true is returned. If the value has already been set, then no saving
413 * or notification occurs, and false is returned.
414 */
415 synchronized boolean set(Object entry) {
416 if (this.entry != unset) {
417 return false;
418 }
419 this.entry = entry;
420 notifyAll();
421 return true;
422 }
423
424 /**
425 * Returns the value contained by this EntryFuture, blocking if
426 * necessary until a value is set.
427 */
428 synchronized Object get() {
429 boolean interrupted = false;
430 while (entry == unset) {
431 try {
432 wait();
433 } catch (InterruptedException ex) {
434 interrupted = true;
435 }
436 }
437 if (interrupted) {
438 AccessController.doPrivileged(
439 new PrivilegedAction<>() {
440 public Void run() {
441 Thread.currentThread().interrupt();
442 return null;
443 }
444 }
445 );
446 }
447 return entry;
448 }
449
450 /**
451 * Returns the thread that created this EntryFuture.
452 */
453 Thread getOwner() {
454 return owner;
455 }
456 }
457
458 /**
459 * Creates local class descriptor representing given class.
460 */
461 private ObjectStreamClass(final Class<?> cl) {
462 this.cl = cl;
463 name = cl.getName();
464 isProxy = Proxy.isProxyClass(cl);
465 isEnum = Enum.class.isAssignableFrom(cl);
466 serializable = Serializable.class.isAssignableFrom(cl);
467 externalizable = Externalizable.class.isAssignableFrom(cl);
468
469 Class<?> superCl = cl.getSuperclass();
470 superDesc = (superCl != null) ? lookup(superCl, false) : null;
471 localDesc = this;
472
473 if (serializable) {
474 AccessController.doPrivileged(new PrivilegedAction<>() {
475 public Void run() {
476 if (isEnum) {
477 suid = Long.valueOf(0);
478 fields = NO_FIELDS;
479 return null;
480 }
481 if (cl.isArray()) {
482 fields = NO_FIELDS;
483 return null;
484 }
485
486 suid = getDeclaredSUID(cl);
487 try {
488 fields = getSerialFields(cl);
489 computeFieldOffsets();
490 } catch (InvalidClassException e) {
491 serializeEx = deserializeEx =
492 new ExceptionInfo(e.classname, e.getMessage());
493 fields = NO_FIELDS;
494 }
495
496 if (externalizable) {
497 cons = getExternalizableConstructor(cl);
498 } else {
499 cons = getSerializableConstructor(cl);
500 writeObjectMethod = getPrivateMethod(cl, "writeObject",
501 new Class<?>[] { ObjectOutputStream.class },
502 Void.TYPE);
503 readObjectMethod = getPrivateMethod(cl, "readObject",
504 new Class<?>[] { ObjectInputStream.class },
505 Void.TYPE);
506 readObjectNoDataMethod = getPrivateMethod(
507 cl, "readObjectNoData", null, Void.TYPE);
508 hasWriteObjectData = (writeObjectMethod != null);
509 }
510 writeReplaceMethod = getInheritableMethod(
511 cl, "writeReplace", null, Object.class);
512 readResolveMethod = getInheritableMethod(
513 cl, "readResolve", null, Object.class);
514 return null;
515 }
516 });
517 } else {
518 suid = Long.valueOf(0);
519 fields = NO_FIELDS;
520 }
521
522 try {
523 fieldRefl = getReflector(fields, this);
524 } catch (InvalidClassException ex) {
525 // field mismatches impossible when matching local fields vs. self
526 throw new InternalError(ex);
527 }
528
529 if (deserializeEx == null) {
530 if (isEnum) {
531 deserializeEx = new ExceptionInfo(name, "enum type");
532 } else if (cons == null) {
533 deserializeEx = new ExceptionInfo(name, "no valid constructor");
534 }
535 }
536 for (int i = 0; i < fields.length; i++) {
537 if (fields[i].getField() == null) {
538 defaultSerializeEx = new ExceptionInfo(
539 name, "unmatched serializable field(s) declared");
540 }
541 }
542 initialized = true;
543 }
544
545 /**
546 * Creates blank class descriptor which should be initialized via a
547 * subsequent call to initProxy(), initNonProxy() or readNonProxy().
548 */
549 ObjectStreamClass() {
550 }
551
552 /**
553 * Initializes class descriptor representing a proxy class.
554 */
555 void initProxy(Class<?> cl,
556 ClassNotFoundException resolveEx,
557 ObjectStreamClass superDesc)
558 throws InvalidClassException
559 {
560 ObjectStreamClass osc = null;
561 if (cl != null) {
562 osc = lookup(cl, true);
563 if (!osc.isProxy) {
564 throw new InvalidClassException(
565 "cannot bind proxy descriptor to a non-proxy class");
566 }
567 }
568 this.cl = cl;
569 this.resolveEx = resolveEx;
570 this.superDesc = superDesc;
571 isProxy = true;
572 serializable = true;
573 suid = Long.valueOf(0);
574 fields = NO_FIELDS;
575 if (osc != null) {
576 localDesc = osc;
577 name = localDesc.name;
578 externalizable = localDesc.externalizable;
579 writeReplaceMethod = localDesc.writeReplaceMethod;
580 readResolveMethod = localDesc.readResolveMethod;
581 deserializeEx = localDesc.deserializeEx;
582 cons = localDesc.cons;
583 }
584 fieldRefl = getReflector(fields, localDesc);
585 initialized = true;
586 }
587
588 /**
589 * Initializes class descriptor representing a non-proxy class.
590 */
591 void initNonProxy(ObjectStreamClass model,
592 Class<?> cl,
593 ClassNotFoundException resolveEx,
594 ObjectStreamClass superDesc)
595 throws InvalidClassException
596 {
597 long suid = Long.valueOf(model.getSerialVersionUID());
598 ObjectStreamClass osc = null;
599 if (cl != null) {
600 osc = lookup(cl, true);
601 if (osc.isProxy) {
602 throw new InvalidClassException(
603 "cannot bind non-proxy descriptor to a proxy class");
604 }
605 if (model.isEnum != osc.isEnum) {
606 throw new InvalidClassException(model.isEnum ?
607 "cannot bind enum descriptor to a non-enum class" :
608 "cannot bind non-enum descriptor to an enum class");
609 }
610
611 if (model.serializable == osc.serializable &&
612 !cl.isArray() &&
613 suid != osc.getSerialVersionUID()) {
614 throw new InvalidClassException(osc.name,
615 "local class incompatible: " +
616 "stream classdesc serialVersionUID = " + suid +
617 ", local class serialVersionUID = " +
618 osc.getSerialVersionUID());
619 }
620
621 if (!classNamesEqual(model.name, osc.name)) {
622 throw new InvalidClassException(osc.name,
623 "local class name incompatible with stream class " +
624 "name \"" + model.name + "\"");
625 }
626
627 if (!model.isEnum) {
628 if ((model.serializable == osc.serializable) &&
629 (model.externalizable != osc.externalizable)) {
630 throw new InvalidClassException(osc.name,
631 "Serializable incompatible with Externalizable");
632 }
633
634 if ((model.serializable != osc.serializable) ||
635 (model.externalizable != osc.externalizable) ||
636 !(model.serializable || model.externalizable)) {
637 deserializeEx = new ExceptionInfo(
638 osc.name, "class invalid for deserialization");
639 }
640 }
641 }
642
643 this.cl = cl;
644 this.resolveEx = resolveEx;
645 this.superDesc = superDesc;
646 name = model.name;
647 this.suid = suid;
648 isProxy = false;
649 isEnum = model.isEnum;
650 serializable = model.serializable;
651 externalizable = model.externalizable;
652 hasBlockExternalData = model.hasBlockExternalData;
653 hasWriteObjectData = model.hasWriteObjectData;
654 fields = model.fields;
655 primDataSize = model.primDataSize;
656 numObjFields = model.numObjFields;
657
658 if (osc != null) {
659 localDesc = osc;
660 writeObjectMethod = localDesc.writeObjectMethod;
661 readObjectMethod = localDesc.readObjectMethod;
662 readObjectNoDataMethod = localDesc.readObjectNoDataMethod;
663 writeReplaceMethod = localDesc.writeReplaceMethod;
664 readResolveMethod = localDesc.readResolveMethod;
665 if (deserializeEx == null) {
666 deserializeEx = localDesc.deserializeEx;
667 }
668 cons = localDesc.cons;
669 }
670
671 fieldRefl = getReflector(fields, localDesc);
672 // reassign to matched fields so as to reflect local unshared settings
673 fields = fieldRefl.getFields();
674 initialized = true;
675 }
676
677 /**
678 * Reads non-proxy class descriptor information from given input stream.
679 * The resulting class descriptor is not fully functional; it can only be
680 * used as input to the ObjectInputStream.resolveClass() and
681 * ObjectStreamClass.initNonProxy() methods.
682 */
683 void readNonProxy(ObjectInputStream in)
684 throws IOException, ClassNotFoundException
685 {
686 name = in.readUTF();
687 suid = Long.valueOf(in.readLong());
688 isProxy = false;
689
690 byte flags = in.readByte();
691 hasWriteObjectData =
692 ((flags & ObjectStreamConstants.SC_WRITE_METHOD) != 0);
693 hasBlockExternalData =
694 ((flags & ObjectStreamConstants.SC_BLOCK_DATA) != 0);
695 externalizable =
696 ((flags & ObjectStreamConstants.SC_EXTERNALIZABLE) != 0);
697 boolean sflag =
698 ((flags & ObjectStreamConstants.SC_SERIALIZABLE) != 0);
699 if (externalizable && sflag) {
700 throw new InvalidClassException(
701 name, "serializable and externalizable flags conflict");
702 }
703 serializable = externalizable || sflag;
704 isEnum = ((flags & ObjectStreamConstants.SC_ENUM) != 0);
705 if (isEnum && suid.longValue() != 0L) {
706 throw new InvalidClassException(name,
707 "enum descriptor has non-zero serialVersionUID: " + suid);
708 }
709
710 int numFields = in.readShort();
711 if (isEnum && numFields != 0) {
712 throw new InvalidClassException(name,
713 "enum descriptor has non-zero field count: " + numFields);
714 }
715 fields = (numFields > 0) ?
716 new ObjectStreamField[numFields] : NO_FIELDS;
717 for (int i = 0; i < numFields; i++) {
718 char tcode = (char) in.readByte();
719 String fname = in.readUTF();
720 String signature = ((tcode == 'L') || (tcode == '[')) ?
721 in.readTypeString() : new String(new char[] { tcode });
722 try {
723 fields[i] = new ObjectStreamField(fname, signature, false);
724 } catch (RuntimeException e) {
725 throw (IOException) new InvalidClassException(name,
726 "invalid descriptor for field " + fname).initCause(e);
727 }
728 }
729 computeFieldOffsets();
730 }
731
732 /**
733 * Writes non-proxy class descriptor information to given output stream.
734 */
735 void writeNonProxy(ObjectOutputStream out) throws IOException {
736 out.writeUTF(name);
737 out.writeLong(getSerialVersionUID());
738
739 byte flags = 0;
740 if (externalizable) {
741 flags |= ObjectStreamConstants.SC_EXTERNALIZABLE;
742 int protocol = out.getProtocolVersion();
743 if (protocol != ObjectStreamConstants.PROTOCOL_VERSION_1) {
744 flags |= ObjectStreamConstants.SC_BLOCK_DATA;
745 }
746 } else if (serializable) {
747 flags |= ObjectStreamConstants.SC_SERIALIZABLE;
748 }
749 if (hasWriteObjectData) {
750 flags |= ObjectStreamConstants.SC_WRITE_METHOD;
751 }
752 if (isEnum) {
753 flags |= ObjectStreamConstants.SC_ENUM;
754 }
755 out.writeByte(flags);
756
757 out.writeShort(fields.length);
758 for (int i = 0; i < fields.length; i++) {
759 ObjectStreamField f = fields[i];
760 out.writeByte(f.getTypeCode());
761 out.writeUTF(f.getName());
762 if (!f.isPrimitive()) {
763 out.writeTypeString(f.getTypeString());
764 }
765 }
766 }
767
768 /**
769 * Returns ClassNotFoundException (if any) thrown while attempting to
770 * resolve local class corresponding to this class descriptor.
771 */
772 ClassNotFoundException getResolveException() {
773 return resolveEx;
774 }
775
776 /**
777 * Throws InternalError if not initialized.
778 */
779 private final void requireInitialized() {
780 if (!initialized)
781 throw new InternalError("Unexpected call when not initialized");
782 }
783
784 /**
785 * Throws an InvalidClassException if object instances referencing this
786 * class descriptor should not be allowed to deserialize. This method does
787 * not apply to deserialization of enum constants.
788 */
789 void checkDeserialize() throws InvalidClassException {
790 requireInitialized();
791 if (deserializeEx != null) {
792 throw deserializeEx.newInvalidClassException();
793 }
794 }
795
796 /**
797 * Throws an InvalidClassException if objects whose class is represented by
798 * this descriptor should not be allowed to serialize. This method does
799 * not apply to serialization of enum constants.
800 */
801 void checkSerialize() throws InvalidClassException {
802 requireInitialized();
803 if (serializeEx != null) {
804 throw serializeEx.newInvalidClassException();
805 }
806 }
807
808 /**
809 * Throws an InvalidClassException if objects whose class is represented by
810 * this descriptor should not be permitted to use default serialization
811 * (e.g., if the class declares serializable fields that do not correspond
812 * to actual fields, and hence must use the GetField API). This method
813 * does not apply to deserialization of enum constants.
814 */
815 void checkDefaultSerialize() throws InvalidClassException {
816 requireInitialized();
817 if (defaultSerializeEx != null) {
818 throw defaultSerializeEx.newInvalidClassException();
819 }
820 }
821
822 /**
823 * Returns superclass descriptor. Note that on the receiving side, the
824 * superclass descriptor may be bound to a class that is not a superclass
825 * of the subclass descriptor's bound class.
826 */
827 ObjectStreamClass getSuperDesc() {
828 requireInitialized();
829 return superDesc;
830 }
831
832 /**
833 * Returns the "local" class descriptor for the class associated with this
834 * class descriptor (i.e., the result of
835 * ObjectStreamClass.lookup(this.forClass())) or null if there is no class
836 * associated with this descriptor.
837 */
838 ObjectStreamClass getLocalDesc() {
839 requireInitialized();
840 return localDesc;
841 }
842
843 /**
844 * Returns arrays of ObjectStreamFields representing the serializable
845 * fields of the represented class. If copy is true, a clone of this class
846 * descriptor's field array is returned, otherwise the array itself is
847 * returned.
848 */
849 ObjectStreamField[] getFields(boolean copy) {
850 return copy ? fields.clone() : fields;
851 }
852
853 /**
854 * Looks up a serializable field of the represented class by name and type.
855 * A specified type of null matches all types, Object.class matches all
856 * non-primitive types, and any other non-null type matches assignable
857 * types only. Returns matching field, or null if no match found.
858 */
859 ObjectStreamField getField(String name, Class<?> type) {
860 for (int i = 0; i < fields.length; i++) {
861 ObjectStreamField f = fields[i];
862 if (f.getName().equals(name)) {
863 if (type == null ||
864 (type == Object.class && !f.isPrimitive()))
865 {
866 return f;
867 }
868 Class<?> ftype = f.getType();
869 if (ftype != null && type.isAssignableFrom(ftype)) {
870 return f;
871 }
872 }
873 }
874 return null;
875 }
876
877 /**
878 * Returns true if class descriptor represents a dynamic proxy class, false
879 * otherwise.
880 */
881 boolean isProxy() {
882 requireInitialized();
883 return isProxy;
884 }
885
886 /**
887 * Returns true if class descriptor represents an enum type, false
888 * otherwise.
889 */
890 boolean isEnum() {
891 requireInitialized();
892 return isEnum;
893 }
894
895 /**
896 * Returns true if represented class implements Externalizable, false
897 * otherwise.
898 */
899 boolean isExternalizable() {
900 requireInitialized();
901 return externalizable;
902 }
903
904 /**
905 * Returns true if represented class implements Serializable, false
906 * otherwise.
907 */
908 boolean isSerializable() {
909 requireInitialized();
910 return serializable;
911 }
912
913 /**
914 * Returns true if class descriptor represents externalizable class that
915 * has written its data in 1.2 (block data) format, false otherwise.
916 */
917 boolean hasBlockExternalData() {
918 requireInitialized();
919 return hasBlockExternalData;
920 }
921
922 /**
923 * Returns true if class descriptor represents serializable (but not
924 * externalizable) class which has written its data via a custom
925 * writeObject() method, false otherwise.
926 */
927 boolean hasWriteObjectData() {
928 requireInitialized();
929 return hasWriteObjectData;
930 }
931
932 /**
933 * Returns true if represented class is serializable/externalizable and can
934 * be instantiated by the serialization runtime--i.e., if it is
935 * externalizable and defines a public no-arg constructor, or if it is
936 * non-externalizable and its first non-serializable superclass defines an
937 * accessible no-arg constructor. Otherwise, returns false.
938 */
939 boolean isInstantiable() {
940 requireInitialized();
941 return (cons != null);
942 }
943
944 /**
945 * Returns true if represented class is serializable (but not
946 * externalizable) and defines a conformant writeObject method. Otherwise,
947 * returns false.
948 */
949 boolean hasWriteObjectMethod() {
950 requireInitialized();
951 return (writeObjectMethod != null);
952 }
953
954 /**
955 * Returns true if represented class is serializable (but not
956 * externalizable) and defines a conformant readObject method. Otherwise,
957 * returns false.
958 */
959 boolean hasReadObjectMethod() {
960 requireInitialized();
961 return (readObjectMethod != null);
962 }
963
964 /**
965 * Returns true if represented class is serializable (but not
966 * externalizable) and defines a conformant readObjectNoData method.
967 * Otherwise, returns false.
968 */
969 boolean hasReadObjectNoDataMethod() {
970 requireInitialized();
971 return (readObjectNoDataMethod != null);
972 }
973
974 /**
975 * Returns true if represented class is serializable or externalizable and
976 * defines a conformant writeReplace method. Otherwise, returns false.
977 */
978 boolean hasWriteReplaceMethod() {
979 requireInitialized();
980 return (writeReplaceMethod != null);
981 }
982
983 /**
984 * Returns true if represented class is serializable or externalizable and
985 * defines a conformant readResolve method. Otherwise, returns false.
986 */
987 boolean hasReadResolveMethod() {
988 requireInitialized();
989 return (readResolveMethod != null);
990 }
991
992 /**
993 * Creates a new instance of the represented class. If the class is
994 * externalizable, invokes its public no-arg constructor; otherwise, if the
995 * class is serializable, invokes the no-arg constructor of the first
996 * non-serializable superclass. Throws UnsupportedOperationException if
997 * this class descriptor is not associated with a class, if the associated
998 * class is non-serializable or if the appropriate no-arg constructor is
999 * inaccessible/unavailable.
1000 */
1001 Object newInstance()
1002 throws InstantiationException, InvocationTargetException,
1003 UnsupportedOperationException
1004 {
1005 requireInitialized();
1006 if (cons != null) {
1007 try {
1008 return cons.newInstance();
1009 } catch (IllegalAccessException ex) {
1010 // should not occur, as access checks have been suppressed
1011 throw new InternalError(ex);
1012 }
1013 } else {
1014 throw new UnsupportedOperationException();
1015 }
1016 }
1017
1018 /**
1019 * Invokes the writeObject method of the represented serializable class.
1020 * Throws UnsupportedOperationException if this class descriptor is not
1021 * associated with a class, or if the class is externalizable,
1022 * non-serializable or does not define writeObject.
1023 */
1024 void invokeWriteObject(Object obj, ObjectOutputStream out)
1025 throws IOException, UnsupportedOperationException
1026 {
1027 requireInitialized();
1028 if (writeObjectMethod != null) {
1029 try {
1030 writeObjectMethod.invoke(obj, new Object[]{ out });
1031 } catch (InvocationTargetException ex) {
1032 Throwable th = ex.getTargetException();
1033 if (th instanceof IOException) {
1034 throw (IOException) th;
1035 } else {
1036 throwMiscException(th);
1037 }
1038 } catch (IllegalAccessException ex) {
1039 // should not occur, as access checks have been suppressed
1040 throw new InternalError(ex);
1041 }
1042 } else {
1043 throw new UnsupportedOperationException();
1044 }
1045 }
1046
1047 /**
1048 * Invokes the readObject method of the represented serializable class.
1049 * Throws UnsupportedOperationException if this class descriptor is not
1050 * associated with a class, or if the class is externalizable,
1051 * non-serializable or does not define readObject.
1052 */
1053 void invokeReadObject(Object obj, ObjectInputStream in)
1054 throws ClassNotFoundException, IOException,
1055 UnsupportedOperationException
1056 {
1057 requireInitialized();
1058 if (readObjectMethod != null) {
1059 try {
1060 readObjectMethod.invoke(obj, new Object[]{ in });
1061 } catch (InvocationTargetException ex) {
1062 Throwable th = ex.getTargetException();
1063 if (th instanceof ClassNotFoundException) {
1064 throw (ClassNotFoundException) th;
1065 } else if (th instanceof IOException) {
1066 throw (IOException) th;
1067 } else {
1068 throwMiscException(th);
1069 }
1070 } catch (IllegalAccessException ex) {
1071 // should not occur, as access checks have been suppressed
1072 throw new InternalError(ex);
1073 }
1074 } else {
1075 throw new UnsupportedOperationException();
1076 }
1077 }
1078
1079 /**
1080 * Invokes the readObjectNoData method of the represented serializable
1081 * class. Throws UnsupportedOperationException if this class descriptor is
1082 * not associated with a class, or if the class is externalizable,
1083 * non-serializable or does not define readObjectNoData.
1084 */
1085 void invokeReadObjectNoData(Object obj)
1086 throws IOException, UnsupportedOperationException
1087 {
1088 requireInitialized();
1089 if (readObjectNoDataMethod != null) {
1090 try {
1091 readObjectNoDataMethod.invoke(obj, (Object[]) null);
1092 } catch (InvocationTargetException ex) {
1093 Throwable th = ex.getTargetException();
1094 if (th instanceof ObjectStreamException) {
1095 throw (ObjectStreamException) th;
1096 } else {
1097 throwMiscException(th);
1098 }
1099 } catch (IllegalAccessException ex) {
1100 // should not occur, as access checks have been suppressed
1101 throw new InternalError(ex);
1102 }
1103 } else {
1104 throw new UnsupportedOperationException();
1105 }
1106 }
1107
1108 /**
1109 * Invokes the writeReplace method of the represented serializable class and
1110 * returns the result. Throws UnsupportedOperationException if this class
1111 * descriptor is not associated with a class, or if the class is
1112 * non-serializable or does not define writeReplace.
1113 */
1114 Object invokeWriteReplace(Object obj)
1115 throws IOException, UnsupportedOperationException
1116 {
1117 requireInitialized();
1118 if (writeReplaceMethod != null) {
1119 try {
1120 return writeReplaceMethod.invoke(obj, (Object[]) null);
1121 } catch (InvocationTargetException ex) {
1122 Throwable th = ex.getTargetException();
1123 if (th instanceof ObjectStreamException) {
1124 throw (ObjectStreamException) th;
1125 } else {
1126 throwMiscException(th);
1127 throw new InternalError(th); // never reached
1128 }
1129 } catch (IllegalAccessException ex) {
1130 // should not occur, as access checks have been suppressed
1131 throw new InternalError(ex);
1132 }
1133 } else {
1134 throw new UnsupportedOperationException();
1135 }
1136 }
1137
1138 /**
1139 * Invokes the readResolve method of the represented serializable class and
1140 * returns the result. Throws UnsupportedOperationException if this class
1141 * descriptor is not associated with a class, or if the class is
1142 * non-serializable or does not define readResolve.
1143 */
1144 Object invokeReadResolve(Object obj)
1145 throws IOException, UnsupportedOperationException
1146 {
1147 requireInitialized();
1148 if (readResolveMethod != null) {
1149 try {
1150 return readResolveMethod.invoke(obj, (Object[]) null);
1151 } catch (InvocationTargetException ex) {
1152 Throwable th = ex.getTargetException();
1153 if (th instanceof ObjectStreamException) {
1154 throw (ObjectStreamException) th;
1155 } else {
1156 throwMiscException(th);
1157 throw new InternalError(th); // never reached
1158 }
1159 } catch (IllegalAccessException ex) {
1160 // should not occur, as access checks have been suppressed
1161 throw new InternalError(ex);
1162 }
1163 } else {
1164 throw new UnsupportedOperationException();
1165 }
1166 }
1167
1168 /**
1169 * Class representing the portion of an object's serialized form allotted
1170 * to data described by a given class descriptor. If "hasData" is false,
1171 * the object's serialized form does not contain data associated with the
1172 * class descriptor.
1173 */
1174 static class ClassDataSlot {
1175
1176 /** class descriptor "occupying" this slot */
1177 final ObjectStreamClass desc;
1178 /** true if serialized form includes data for this slot's descriptor */
1179 final boolean hasData;
1180
1181 ClassDataSlot(ObjectStreamClass desc, boolean hasData) {
1182 this.desc = desc;
1183 this.hasData = hasData;
1184 }
1185 }
1186
1187 /**
1188 * Returns array of ClassDataSlot instances representing the data layout
1189 * (including superclass data) for serialized objects described by this
1190 * class descriptor. ClassDataSlots are ordered by inheritance with those
1191 * containing "higher" superclasses appearing first. The final
1192 * ClassDataSlot contains a reference to this descriptor.
1193 */
1194 ClassDataSlot[] getClassDataLayout() throws InvalidClassException {
1195 // REMIND: synchronize instead of relying on volatile?
1196 if (dataLayout == null) {
1197 dataLayout = getClassDataLayout0();
1198 }
1199 return dataLayout;
1200 }
1201
1202 private ClassDataSlot[] getClassDataLayout0()
1203 throws InvalidClassException
1204 {
1205 ArrayList<ClassDataSlot> slots = new ArrayList<>();
1206 Class<?> start = cl, end = cl;
1207
1208 // locate closest non-serializable superclass
1209 while (end != null && Serializable.class.isAssignableFrom(end)) {
1210 end = end.getSuperclass();
1211 }
1212
1213 HashSet<String> oscNames = new HashSet<>(3);
1214
1215 for (ObjectStreamClass d = this; d != null; d = d.superDesc) {
1216 if (oscNames.contains(d.name)) {
1217 throw new InvalidClassException("Circular reference.");
1218 } else {
1219 oscNames.add(d.name);
1220 }
1221
1222 // search up inheritance hierarchy for class with matching name
1223 String searchName = (d.cl != null) ? d.cl.getName() : d.name;
1224 Class<?> match = null;
1225 for (Class<?> c = start; c != end; c = c.getSuperclass()) {
1226 if (searchName.equals(c.getName())) {
1227 match = c;
1228 break;
1229 }
1230 }
1231
1232 // add "no data" slot for each unmatched class below match
1233 if (match != null) {
1234 for (Class<?> c = start; c != match; c = c.getSuperclass()) {
1235 slots.add(new ClassDataSlot(
1236 ObjectStreamClass.lookup(c, true), false));
1237 }
1238 start = match.getSuperclass();
1239 }
1240
1241 // record descriptor/class pairing
1242 slots.add(new ClassDataSlot(d.getVariantFor(match), true));
1243 }
1244
1245 // add "no data" slot for any leftover unmatched classes
1246 for (Class<?> c = start; c != end; c = c.getSuperclass()) {
1247 slots.add(new ClassDataSlot(
1248 ObjectStreamClass.lookup(c, true), false));
1249 }
1250
1251 // order slots from superclass -> subclass
1252 Collections.reverse(slots);
1253 return slots.toArray(new ClassDataSlot[slots.size()]);
1254 }
1255
1256 /**
1257 * Returns aggregate size (in bytes) of marshalled primitive field values
1258 * for represented class.
1259 */
1260 int getPrimDataSize() {
1261 return primDataSize;
1262 }
1263
1264 /**
1265 * Returns number of non-primitive serializable fields of represented
1266 * class.
1267 */
1268 int getNumObjFields() {
1269 return numObjFields;
1270 }
1271
1272 /**
1273 * Fetches the serializable primitive field values of object obj and
1274 * marshals them into byte array buf starting at offset 0. It is the
1275 * responsibility of the caller to ensure that obj is of the proper type if
1276 * non-null.
1277 */
1278 void getPrimFieldValues(Object obj, byte[] buf) {
1279 fieldRefl.getPrimFieldValues(obj, buf);
1280 }
1281
1282 /**
1283 * Sets the serializable primitive fields of object obj using values
1284 * unmarshalled from byte array buf starting at offset 0. It is the
1285 * responsibility of the caller to ensure that obj is of the proper type if
1286 * non-null.
1287 */
1288 void setPrimFieldValues(Object obj, byte[] buf) {
1289 fieldRefl.setPrimFieldValues(obj, buf);
1290 }
1291
1292 /**
1293 * Fetches the serializable object field values of object obj and stores
1294 * them in array vals starting at offset 0. It is the responsibility of
1295 * the caller to ensure that obj is of the proper type if non-null.
1296 */
1297 void getObjFieldValues(Object obj, Object[] vals) {
1298 fieldRefl.getObjFieldValues(obj, vals);
1299 }
1300
1301 /**
1302 * Checks that the given values, from array vals starting at offset 0,
1303 * are assignable to the given serializable object fields.
1304 * @throws ClassCastException if any value is not assignable
1305 */
1306 void checkObjFieldValueTypes(Object obj, Object[] vals) {
1307 fieldRefl.checkObjectFieldValueTypes(obj, vals);
1308 }
1309
1310 /**
1311 * Sets the serializable object fields of object obj using values from
1312 * array vals starting at offset 0. It is the responsibility of the caller
1313 * to ensure that obj is of the proper type if non-null.
1314 */
1315 void setObjFieldValues(Object obj, Object[] vals) {
1316 fieldRefl.setObjFieldValues(obj, vals);
1317 }
1318
1319 /**
1320 * Calculates and sets serializable field offsets, as well as primitive
1321 * data size and object field count totals. Throws InvalidClassException
1322 * if fields are illegally ordered.
1323 */
1324 private void computeFieldOffsets() throws InvalidClassException {
1325 primDataSize = 0;
1326 numObjFields = 0;
1327 int firstObjIndex = -1;
1328
1329 for (int i = 0; i < fields.length; i++) {
1330 ObjectStreamField f = fields[i];
1331 switch (f.getTypeCode()) {
1332 case 'Z':
1333 case 'B':
1334 f.setOffset(primDataSize++);
1335 break;
1336
1337 case 'C':
1338 case 'S':
1339 f.setOffset(primDataSize);
1340 primDataSize += 2;
1341 break;
1342
1343 case 'I':
1344 case 'F':
1345 f.setOffset(primDataSize);
1346 primDataSize += 4;
1347 break;
1348
1349 case 'J':
1350 case 'D':
1351 f.setOffset(primDataSize);
1352 primDataSize += 8;
1353 break;
1354
1355 case '[':
1356 case 'L':
1357 f.setOffset(numObjFields++);
1358 if (firstObjIndex == -1) {
1359 firstObjIndex = i;
1360 }
1361 break;
1362
1363 default:
1364 throw new InternalError();
1365 }
1366 }
1367 if (firstObjIndex != -1 &&
1368 firstObjIndex + numObjFields != fields.length)
1369 {
1370 throw new InvalidClassException(name, "illegal field order");
1371 }
1372 }
1373
1374 /**
1375 * If given class is the same as the class associated with this class
1376 * descriptor, returns reference to this class descriptor. Otherwise,
1377 * returns variant of this class descriptor bound to given class.
1378 */
1379 private ObjectStreamClass getVariantFor(Class<?> cl)
1380 throws InvalidClassException
1381 {
1382 if (this.cl == cl) {
1383 return this;
1384 }
1385 ObjectStreamClass desc = new ObjectStreamClass();
1386 if (isProxy) {
1387 desc.initProxy(cl, null, superDesc);
1388 } else {
1389 desc.initNonProxy(this, cl, null, superDesc);
1390 }
1391 return desc;
1392 }
1393
1394 /**
1395 * Returns public no-arg constructor of given class, or null if none found.
1396 * Access checks are disabled on the returned constructor (if any), since
1397 * the defining class may still be non-public.
1398 */
1399 private static Constructor<?> getExternalizableConstructor(Class<?> cl) {
1400 try {
1401 Constructor<?> cons = cl.getDeclaredConstructor((Class<?>[]) null);
1402 cons.setAccessible(true);
1403 return ((cons.getModifiers() & Modifier.PUBLIC) != 0) ?
1404 cons : null;
1405 } catch (NoSuchMethodException ex) {
1406 return null;
1407 }
1408 }
1409
1410 /**
1411 * Returns subclass-accessible no-arg constructor of first non-serializable
1412 * superclass, or null if none found. Access checks are disabled on the
1413 * returned constructor (if any).
1414 */
1415 private static Constructor<?> getSerializableConstructor(Class<?> cl) {
1416 Class<?> initCl = cl;
1417 while (Serializable.class.isAssignableFrom(initCl)) {
1418 if ((initCl = initCl.getSuperclass()) == null) {
1419 return null;
1420 }
1421 }
1422 try {
1423 Constructor<?> cons = initCl.getDeclaredConstructor((Class<?>[]) null);
1424 int mods = cons.getModifiers();
1425 if ((mods & Modifier.PRIVATE) != 0 ||
1426 ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) == 0 &&
1427 !packageEquals(cl, initCl)))
1428 {
1429 return null;
1430 }
1431 cons = reflFactory.newConstructorForSerialization(cl, cons);
1432 cons.setAccessible(true);
1433 return cons;
1434 } catch (NoSuchMethodException ex) {
1435 return null;
1436 }
1437 }
1438
1439 /**
1440 * Returns non-static, non-abstract method with given signature provided it
1441 * is defined by or accessible (via inheritance) by the given class, or
1442 * null if no match found. Access checks are disabled on the returned
1443 * method (if any).
1444 */
1445 private static Method getInheritableMethod(Class<?> cl, String name,
1446 Class<?>[] argTypes,
1447 Class<?> returnType)
1448 {
1449 Method meth = null;
1450 Class<?> defCl = cl;
1451 while (defCl != null) {
1452 try {
1453 meth = defCl.getDeclaredMethod(name, argTypes);
1454 break;
1455 } catch (NoSuchMethodException ex) {
1456 defCl = defCl.getSuperclass();
1457 }
1458 }
1459
1460 if ((meth == null) || (meth.getReturnType() != returnType)) {
1461 return null;
1462 }
1463 meth.setAccessible(true);
1464 int mods = meth.getModifiers();
1465 if ((mods & (Modifier.STATIC | Modifier.ABSTRACT)) != 0) {
1466 return null;
1467 } else if ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) != 0) {
1468 return meth;
1469 } else if ((mods & Modifier.PRIVATE) != 0) {
1470 return (cl == defCl) ? meth : null;
1471 } else {
1472 return packageEquals(cl, defCl) ? meth : null;
1473 }
1474 }
1475
1476 /**
1477 * Returns non-static private method with given signature defined by given
1478 * class, or null if none found. Access checks are disabled on the
1479 * returned method (if any).
1480 */
1481 private static Method getPrivateMethod(Class<?> cl, String name,
1482 Class<?>[] argTypes,
1483 Class<?> returnType)
1484 {
1485 try {
1486 Method meth = cl.getDeclaredMethod(name, argTypes);
1487 meth.setAccessible(true);
1488 int mods = meth.getModifiers();
1489 return ((meth.getReturnType() == returnType) &&
1490 ((mods & Modifier.STATIC) == 0) &&
1491 ((mods & Modifier.PRIVATE) != 0)) ? meth : null;
1492 } catch (NoSuchMethodException ex) {
1493 return null;
1494 }
1495 }
1496
1497 /**
1498 * Returns true if classes are defined in the same runtime package, false
1499 * otherwise.
1500 */
1501 private static boolean packageEquals(Class<?> cl1, Class<?> cl2) {
1502 return (cl1.getClassLoader() == cl2.getClassLoader() &&
1503 getPackageName(cl1).equals(getPackageName(cl2)));
1504 }
1505
1506 /**
1507 * Returns package name of given class.
1508 */
1509 private static String getPackageName(Class<?> cl) {
1510 String s = cl.getName();
1511 int i = s.lastIndexOf('[');
1512 i = (i < 0) ? 0 : i + 2;
1513 int j = s.lastIndexOf('.');
1514 return (i < j) ? s.substring(i, j) : "";
1515 }
1516
1517 /**
1518 * Compares class names for equality, ignoring package names. Returns true
1519 * if class names equal, false otherwise.
1520 */
1521 private static boolean classNamesEqual(String name1, String name2) {
1522 int idx1 = name1.lastIndexOf('.') + 1;
1523 int idx2 = name2.lastIndexOf('.') + 1;
1524 int len1 = name1.length() - idx1;
1525 int len2 = name2.length() - idx2;
1526 return len1 == len2 &&
1527 name1.regionMatches(idx1, name2, idx2, len1);
1528 }
1529
1530 /**
1531 * Returns JVM type signature for given list of parameters and return type.
1532 */
1533 private static String getMethodSignature(Class<?>[] paramTypes,
1534 Class<?> retType)
1535 {
1536 StringBuilder sb = new StringBuilder();
1537 sb.append('(');
1538 for (int i = 0; i < paramTypes.length; i++) {
1539 appendClassSignature(sb, paramTypes[i]);
1540 }
1541 sb.append(')');
1542 appendClassSignature(sb, retType);
1543 return sb.toString();
1544 }
1545
1546 /**
1547 * Convenience method for throwing an exception that is either a
1548 * RuntimeException, Error, or of some unexpected type (in which case it is
1549 * wrapped inside an IOException).
1550 */
1551 private static void throwMiscException(Throwable th) throws IOException {
1552 if (th instanceof RuntimeException) {
1553 throw (RuntimeException) th;
1554 } else if (th instanceof Error) {
1555 throw (Error) th;
1556 } else {
1557 IOException ex = new IOException("unexpected exception type");
1558 ex.initCause(th);
1559 throw ex;
1560 }
1561 }
1562
1563 /**
1564 * Returns ObjectStreamField array describing the serializable fields of
1565 * the given class. Serializable fields backed by an actual field of the
1566 * class are represented by ObjectStreamFields with corresponding non-null
1567 * Field objects. Throws InvalidClassException if the (explicitly
1568 * declared) serializable fields are invalid.
1569 */
1570 private static ObjectStreamField[] getSerialFields(Class<?> cl)
1571 throws InvalidClassException
1572 {
1573 ObjectStreamField[] fields;
1574 if (Serializable.class.isAssignableFrom(cl) &&
1575 !Externalizable.class.isAssignableFrom(cl) &&
1576 !Proxy.isProxyClass(cl) &&
1577 !cl.isInterface())
1578 {
1579 if ((fields = getDeclaredSerialFields(cl)) == null) {
1580 fields = getDefaultSerialFields(cl);
1581 }
1582 Arrays.sort(fields);
1583 } else {
1584 fields = NO_FIELDS;
1585 }
1586 return fields;
1587 }
1588
1589 /**
1590 * Returns serializable fields of given class as defined explicitly by a
1591 * "serialPersistentFields" field, or null if no appropriate
1592 * "serialPersistentFields" field is defined. Serializable fields backed
1593 * by an actual field of the class are represented by ObjectStreamFields
1594 * with corresponding non-null Field objects. For compatibility with past
1595 * releases, a "serialPersistentFields" field with a null value is
1596 * considered equivalent to not declaring "serialPersistentFields". Throws
1597 * InvalidClassException if the declared serializable fields are
1598 * invalid--e.g., if multiple fields share the same name.
1599 */
1600 private static ObjectStreamField[] getDeclaredSerialFields(Class<?> cl)
1601 throws InvalidClassException
1602 {
1603 ObjectStreamField[] serialPersistentFields = null;
1604 try {
1605 Field f = cl.getDeclaredField("serialPersistentFields");
1606 int mask = Modifier.PRIVATE | Modifier.STATIC | Modifier.FINAL;
1607 if ((f.getModifiers() & mask) == mask) {
1608 f.setAccessible(true);
1609 serialPersistentFields = (ObjectStreamField[]) f.get(null);
1610 }
1611 } catch (Exception ex) {
1612 }
1613 if (serialPersistentFields == null) {
1614 return null;
1615 } else if (serialPersistentFields.length == 0) {
1616 return NO_FIELDS;
1617 }
1618
1619 ObjectStreamField[] boundFields =
1620 new ObjectStreamField[serialPersistentFields.length];
1621 Set<String> fieldNames = new HashSet<>(serialPersistentFields.length);
1622
1623 for (int i = 0; i < serialPersistentFields.length; i++) {
1624 ObjectStreamField spf = serialPersistentFields[i];
1625
1626 String fname = spf.getName();
1627 if (fieldNames.contains(fname)) {
1628 throw new InvalidClassException(
1629 "multiple serializable fields named " + fname);
1630 }
1631 fieldNames.add(fname);
1632
1633 try {
1634 Field f = cl.getDeclaredField(fname);
1635 if ((f.getType() == spf.getType()) &&
1636 ((f.getModifiers() & Modifier.STATIC) == 0))
1637 {
1638 boundFields[i] =
1639 new ObjectStreamField(f, spf.isUnshared(), true);
1640 }
1641 } catch (NoSuchFieldException ex) {
1642 }
1643 if (boundFields[i] == null) {
1644 boundFields[i] = new ObjectStreamField(
1645 fname, spf.getType(), spf.isUnshared());
1646 }
1647 }
1648 return boundFields;
1649 }
1650
1651 /**
1652 * Returns array of ObjectStreamFields corresponding to all non-static
1653 * non-transient fields declared by given class. Each ObjectStreamField
1654 * contains a Field object for the field it represents. If no default
1655 * serializable fields exist, NO_FIELDS is returned.
1656 */
1657 private static ObjectStreamField[] getDefaultSerialFields(Class<?> cl) {
1658 Field[] clFields = cl.getDeclaredFields();
1659 ArrayList<ObjectStreamField> list = new ArrayList<>();
1660 int mask = Modifier.STATIC | Modifier.TRANSIENT;
1661
1662 for (int i = 0; i < clFields.length; i++) {
1663 if ((clFields[i].getModifiers() & mask) == 0) {
1664 list.add(new ObjectStreamField(clFields[i], false, true));
1665 }
1666 }
1667 int size = list.size();
1668 return (size == 0) ? NO_FIELDS :
1669 list.toArray(new ObjectStreamField[size]);
1670 }
1671
1672 /**
1673 * Returns explicit serial version UID value declared by given class, or
1674 * null if none.
1675 */
1676 private static Long getDeclaredSUID(Class<?> cl) {
1677 try {
1678 Field f = cl.getDeclaredField("serialVersionUID");
1679 int mask = Modifier.STATIC | Modifier.FINAL;
1680 if ((f.getModifiers() & mask) == mask) {
1681 f.setAccessible(true);
1682 return Long.valueOf(f.getLong(null));
1683 }
1684 } catch (Exception ex) {
1685 }
1686 return null;
1687 }
1688
1689 /**
1690 * Computes the default serial version UID value for the given class.
1691 */
1692 private static long computeDefaultSUID(Class<?> cl) {
1693 if (!Serializable.class.isAssignableFrom(cl) || Proxy.isProxyClass(cl))
1694 {
1695 return 0L;
1696 }
1697
1698 try {
1699 ByteArrayOutputStream bout = new ByteArrayOutputStream();
1700 DataOutputStream dout = new DataOutputStream(bout);
1701
1702 dout.writeUTF(cl.getName());
1703
1704 int classMods = cl.getModifiers() &
1705 (Modifier.PUBLIC | Modifier.FINAL |
1706 Modifier.INTERFACE | Modifier.ABSTRACT);
1707
1708 /*
1709 * compensate for javac bug in which ABSTRACT bit was set for an
1710 * interface only if the interface declared methods
1711 */
1712 Method[] methods = cl.getDeclaredMethods();
1713 if ((classMods & Modifier.INTERFACE) != 0) {
1714 classMods = (methods.length > 0) ?
1715 (classMods | Modifier.ABSTRACT) :
1716 (classMods & ~Modifier.ABSTRACT);
1717 }
1718 dout.writeInt(classMods);
1719
1720 if (!cl.isArray()) {
1721 /*
1722 * compensate for change in 1.2FCS in which
1723 * Class.getInterfaces() was modified to return Cloneable and
1724 * Serializable for array classes.
1725 */
1726 Class<?>[] interfaces = cl.getInterfaces();
1727 String[] ifaceNames = new String[interfaces.length];
1728 for (int i = 0; i < interfaces.length; i++) {
1729 ifaceNames[i] = interfaces[i].getName();
1730 }
1731 Arrays.sort(ifaceNames);
1732 for (int i = 0; i < ifaceNames.length; i++) {
1733 dout.writeUTF(ifaceNames[i]);
1734 }
1735 }
1736
1737 Field[] fields = cl.getDeclaredFields();
1738 MemberSignature[] fieldSigs = new MemberSignature[fields.length];
1739 for (int i = 0; i < fields.length; i++) {
1740 fieldSigs[i] = new MemberSignature(fields[i]);
1741 }
1742 Arrays.sort(fieldSigs, new Comparator<>() {
1743 public int compare(MemberSignature ms1, MemberSignature ms2) {
1744 return ms1.name.compareTo(ms2.name);
1745 }
1746 });
1747 for (int i = 0; i < fieldSigs.length; i++) {
1748 MemberSignature sig = fieldSigs[i];
1749 int mods = sig.member.getModifiers() &
1750 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1751 Modifier.STATIC | Modifier.FINAL | Modifier.VOLATILE |
1752 Modifier.TRANSIENT);
1753 if (((mods & Modifier.PRIVATE) == 0) ||
1754 ((mods & (Modifier.STATIC | Modifier.TRANSIENT)) == 0))
1755 {
1756 dout.writeUTF(sig.name);
1757 dout.writeInt(mods);
1758 dout.writeUTF(sig.signature);
1759 }
1760 }
1761
1762 if (hasStaticInitializer(cl)) {
1763 dout.writeUTF("<clinit>");
1764 dout.writeInt(Modifier.STATIC);
1765 dout.writeUTF("()V");
1766 }
1767
1768 Constructor<?>[] cons = cl.getDeclaredConstructors();
1769 MemberSignature[] consSigs = new MemberSignature[cons.length];
1770 for (int i = 0; i < cons.length; i++) {
1771 consSigs[i] = new MemberSignature(cons[i]);
1772 }
1773 Arrays.sort(consSigs, new Comparator<>() {
1774 public int compare(MemberSignature ms1, MemberSignature ms2) {
1775 return ms1.signature.compareTo(ms2.signature);
1776 }
1777 });
1778 for (int i = 0; i < consSigs.length; i++) {
1779 MemberSignature sig = consSigs[i];
1780 int mods = sig.member.getModifiers() &
1781 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1782 Modifier.STATIC | Modifier.FINAL |
1783 Modifier.SYNCHRONIZED | Modifier.NATIVE |
1784 Modifier.ABSTRACT | Modifier.STRICT);
1785 if ((mods & Modifier.PRIVATE) == 0) {
1786 dout.writeUTF("<init>");
1787 dout.writeInt(mods);
1788 dout.writeUTF(sig.signature.replace('/', '.'));
1789 }
1790 }
1791
1792 MemberSignature[] methSigs = new MemberSignature[methods.length];
1793 for (int i = 0; i < methods.length; i++) {
1794 methSigs[i] = new MemberSignature(methods[i]);
1795 }
1796 Arrays.sort(methSigs, new Comparator<>() {
1797 public int compare(MemberSignature ms1, MemberSignature ms2) {
1798 int comp = ms1.name.compareTo(ms2.name);
1799 if (comp == 0) {
1800 comp = ms1.signature.compareTo(ms2.signature);
1801 }
1802 return comp;
1803 }
1804 });
1805 for (int i = 0; i < methSigs.length; i++) {
1806 MemberSignature sig = methSigs[i];
1807 int mods = sig.member.getModifiers() &
1808 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1809 Modifier.STATIC | Modifier.FINAL |
1810 Modifier.SYNCHRONIZED | Modifier.NATIVE |
1811 Modifier.ABSTRACT | Modifier.STRICT);
1812 if ((mods & Modifier.PRIVATE) == 0) {
1813 dout.writeUTF(sig.name);
1814 dout.writeInt(mods);
1815 dout.writeUTF(sig.signature.replace('/', '.'));
1816 }
1817 }
1818
1819 dout.flush();
1820
1821 MessageDigest md = MessageDigest.getInstance("SHA");
1822 byte[] hashBytes = md.digest(bout.toByteArray());
1823 long hash = 0;
1824 for (int i = Math.min(hashBytes.length, 8) - 1; i >= 0; i--) {
1825 hash = (hash << 8) | (hashBytes[i] & 0xFF);
1826 }
1827 return hash;
1828 } catch (IOException ex) {
1829 throw new InternalError(ex);
1830 } catch (NoSuchAlgorithmException ex) {
1831 throw new SecurityException(ex.getMessage());
1832 }
1833 }
1834
1835 /**
1836 * Returns true if the given class defines a static initializer method,
1837 * false otherwise.
1838 */
1839 private static native boolean hasStaticInitializer(Class<?> cl);
1840
1841 /**
1842 * Class for computing and caching field/constructor/method signatures
1843 * during serialVersionUID calculation.
1844 */
1845 private static class MemberSignature {
1846
1847 public final Member member;
1848 public final String name;
1849 public final String signature;
1850
1851 public MemberSignature(Field field) {
1852 member = field;
1853 name = field.getName();
1854 signature = getClassSignature(field.getType());
1855 }
1856
1857 public MemberSignature(Constructor<?> cons) {
1858 member = cons;
1859 name = cons.getName();
1860 signature = getMethodSignature(
1861 cons.getParameterTypes(), Void.TYPE);
1862 }
1863
1864 public MemberSignature(Method meth) {
1865 member = meth;
1866 name = meth.getName();
1867 signature = getMethodSignature(
1868 meth.getParameterTypes(), meth.getReturnType());
1869 }
1870 }
1871
1872 /**
1873 * Class for setting and retrieving serializable field values in batch.
1874 */
1875 // REMIND: dynamically generate these?
1876 private static class FieldReflector {
1877
1878 /** handle for performing unsafe operations */
1879 private static final Unsafe unsafe = Unsafe.getUnsafe();
1880
1881 /** fields to operate on */
1882 private final ObjectStreamField[] fields;
1883 /** number of primitive fields */
1884 private final int numPrimFields;
1885 /** unsafe field keys for reading fields - may contain dupes */
1886 private final long[] readKeys;
1887 /** unsafe fields keys for writing fields - no dupes */
1888 private final long[] writeKeys;
1889 /** field data offsets */
1890 private final int[] offsets;
1891 /** field type codes */
1892 private final char[] typeCodes;
1893 /** field types */
1894 private final Class<?>[] types;
1895
1896 /**
1897 * Constructs FieldReflector capable of setting/getting values from the
1898 * subset of fields whose ObjectStreamFields contain non-null
1899 * reflective Field objects. ObjectStreamFields with null Fields are
1900 * treated as filler, for which get operations return default values
1901 * and set operations discard given values.
1902 */
1903 FieldReflector(ObjectStreamField[] fields) {
1904 this.fields = fields;
1905 int nfields = fields.length;
1906 readKeys = new long[nfields];
1907 writeKeys = new long[nfields];
1908 offsets = new int[nfields];
1909 typeCodes = new char[nfields];
1910 ArrayList<Class<?>> typeList = new ArrayList<>();
1911 Set<Long> usedKeys = new HashSet<>();
1912
1913
1914 for (int i = 0; i < nfields; i++) {
1915 ObjectStreamField f = fields[i];
1916 Field rf = f.getField();
1917 long key = (rf != null) ?
1918 unsafe.objectFieldOffset(rf) : Unsafe.INVALID_FIELD_OFFSET;
1919 readKeys[i] = key;
1920 writeKeys[i] = usedKeys.add(key) ?
1921 key : Unsafe.INVALID_FIELD_OFFSET;
1922 offsets[i] = f.getOffset();
1923 typeCodes[i] = f.getTypeCode();
1924 if (!f.isPrimitive()) {
1925 typeList.add((rf != null) ? rf.getType() : null);
1926 }
1927 }
1928
1929 types = typeList.toArray(new Class<?>[typeList.size()]);
1930 numPrimFields = nfields - types.length;
1931 }
1932
1933 /**
1934 * Returns list of ObjectStreamFields representing fields operated on
1935 * by this reflector. The shared/unshared values and Field objects
1936 * contained by ObjectStreamFields in the list reflect their bindings
1937 * to locally defined serializable fields.
1938 */
1939 ObjectStreamField[] getFields() {
1940 return fields;
1941 }
1942
1943 /**
1944 * Fetches the serializable primitive field values of object obj and
1945 * marshals them into byte array buf starting at offset 0. The caller
1946 * is responsible for ensuring that obj is of the proper type.
1947 */
1948 void getPrimFieldValues(Object obj, byte[] buf) {
1949 if (obj == null) {
1950 throw new NullPointerException();
1951 }
1952 /* assuming checkDefaultSerialize() has been called on the class
1953 * descriptor this FieldReflector was obtained from, no field keys
1954 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET.
1955 */
1956 for (int i = 0; i < numPrimFields; i++) {
1957 long key = readKeys[i];
1958 int off = offsets[i];
1959 switch (typeCodes[i]) {
1960 case 'Z':
1961 Bits.putBoolean(buf, off, unsafe.getBoolean(obj, key));
1962 break;
1963
1964 case 'B':
1965 buf[off] = unsafe.getByte(obj, key);
1966 break;
1967
1968 case 'C':
1969 Bits.putChar(buf, off, unsafe.getChar(obj, key));
1970 break;
1971
1972 case 'S':
1973 Bits.putShort(buf, off, unsafe.getShort(obj, key));
1974 break;
1975
1976 case 'I':
1977 Bits.putInt(buf, off, unsafe.getInt(obj, key));
1978 break;
1979
1980 case 'F':
1981 Bits.putFloat(buf, off, unsafe.getFloat(obj, key));
1982 break;
1983
1984 case 'J':
1985 Bits.putLong(buf, off, unsafe.getLong(obj, key));
1986 break;
1987
1988 case 'D':
1989 Bits.putDouble(buf, off, unsafe.getDouble(obj, key));
1990 break;
1991
1992 default:
1993 throw new InternalError();
1994 }
1995 }
1996 }
1997
1998 /**
1999 * Sets the serializable primitive fields of object obj using values
2000 * unmarshalled from byte array buf starting at offset 0. The caller
2001 * is responsible for ensuring that obj is of the proper type.
2002 */
2003 void setPrimFieldValues(Object obj, byte[] buf) {
2004 if (obj == null) {
2005 throw new NullPointerException();
2006 }
2007 for (int i = 0; i < numPrimFields; i++) {
2008 long key = writeKeys[i];
2009 if (key == Unsafe.INVALID_FIELD_OFFSET) {
2010 continue; // discard value
2011 }
2012 int off = offsets[i];
2013 switch (typeCodes[i]) {
2014 case 'Z':
2015 unsafe.putBoolean(obj, key, Bits.getBoolean(buf, off));
2016 break;
2017
2018 case 'B':
2019 unsafe.putByte(obj, key, buf[off]);
2020 break;
2021
2022 case 'C':
2023 unsafe.putChar(obj, key, Bits.getChar(buf, off));
2024 break;
2025
2026 case 'S':
2027 unsafe.putShort(obj, key, Bits.getShort(buf, off));
2028 break;
2029
2030 case 'I':
2031 unsafe.putInt(obj, key, Bits.getInt(buf, off));
2032 break;
2033
2034 case 'F':
2035 unsafe.putFloat(obj, key, Bits.getFloat(buf, off));
2036 break;
2037
2038 case 'J':
2039 unsafe.putLong(obj, key, Bits.getLong(buf, off));
2040 break;
2041
2042 case 'D':
2043 unsafe.putDouble(obj, key, Bits.getDouble(buf, off));
2044 break;
2045
2046 default:
2047 throw new InternalError();
2048 }
2049 }
2050 }
2051
2052 /**
2053 * Fetches the serializable object field values of object obj and
2054 * stores them in array vals starting at offset 0. The caller is
2055 * responsible for ensuring that obj is of the proper type.
2056 */
2057 void getObjFieldValues(Object obj, Object[] vals) {
2058 if (obj == null) {
2059 throw new NullPointerException();
2060 }
2061 /* assuming checkDefaultSerialize() has been called on the class
2062 * descriptor this FieldReflector was obtained from, no field keys
2063 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET.
2064 */
2065 for (int i = numPrimFields; i < fields.length; i++) {
2066 switch (typeCodes[i]) {
2067 case 'L':
2068 case '[':
2069 vals[offsets[i]] = unsafe.getObject(obj, readKeys[i]);
2070 break;
2071
2072 default:
2073 throw new InternalError();
2074 }
2075 }
2076 }
2077
2078 /**
2079 * Checks that the given values, from array vals starting at offset 0,
2080 * are assignable to the given serializable object fields.
2081 * @throws ClassCastException if any value is not assignable
2082 */
2083 void checkObjectFieldValueTypes(Object obj, Object[] vals) {
2084 setObjFieldValues(obj, vals, true);
2085 }
2086
2087 /**
2088 * Sets the serializable object fields of object obj using values from
2089 * array vals starting at offset 0. The caller is responsible for
2090 * ensuring that obj is of the proper type; however, attempts to set a
2091 * field with a value of the wrong type will trigger an appropriate
2092 * ClassCastException.
2093 */
2094 void setObjFieldValues(Object obj, Object[] vals) {
2095 setObjFieldValues(obj, vals, false);
2096 }
2097
2098 private void setObjFieldValues(Object obj, Object[] vals, boolean dryRun) {
2099 if (obj == null) {
2100 throw new NullPointerException();
2101 }
2102 for (int i = numPrimFields; i < fields.length; i++) {
2103 long key = writeKeys[i];
2104 if (key == Unsafe.INVALID_FIELD_OFFSET) {
2105 continue; // discard value
2106 }
2107 switch (typeCodes[i]) {
2108 case 'L':
2109 case '[':
2110 Object val = vals[offsets[i]];
2111 if (val != null &&
2112 !types[i - numPrimFields].isInstance(val))
2113 {
2114 Field f = fields[i].getField();
2115 throw new ClassCastException(
2116 "cannot assign instance of " +
2117 val.getClass().getName() + " to field " +
2118 f.getDeclaringClass().getName() + "." +
2119 f.getName() + " of type " +
2120 f.getType().getName() + " in instance of " +
2121 obj.getClass().getName());
2122 }
2123 if (!dryRun)
2124 unsafe.putObject(obj, key, val);
2125 break;
2126
2127 default:
2128 throw new InternalError();
2129 }
2130 }
2131 }
2132 }
2133
2134 /**
2135 * Matches given set of serializable fields with serializable fields
2136 * described by the given local class descriptor, and returns a
2137 * FieldReflector instance capable of setting/getting values from the
2138 * subset of fields that match (non-matching fields are treated as filler,
2139 * for which get operations return default values and set operations
2140 * discard given values). Throws InvalidClassException if unresolvable
2141 * type conflicts exist between the two sets of fields.
2142 */
2143 private static FieldReflector getReflector(ObjectStreamField[] fields,
2144 ObjectStreamClass localDesc)
2145 throws InvalidClassException
2146 {
2147 // class irrelevant if no fields
2148 Class<?> cl = (localDesc != null && fields.length > 0) ?
2149 localDesc.cl : null;
2150 processQueue(Caches.reflectorsQueue, Caches.reflectors);
2151 FieldReflectorKey key = new FieldReflectorKey(cl, fields,
2152 Caches.reflectorsQueue);
2153 Reference<?> ref = Caches.reflectors.get(key);
2154 Object entry = null;
2155 if (ref != null) {
2156 entry = ref.get();
2157 }
2158 EntryFuture future = null;
2159 if (entry == null) {
2160 EntryFuture newEntry = new EntryFuture();
2161 Reference<?> newRef = new SoftReference<>(newEntry);
2162 do {
2163 if (ref != null) {
2164 Caches.reflectors.remove(key, ref);
2165 }
2166 ref = Caches.reflectors.putIfAbsent(key, newRef);
2167 if (ref != null) {
2168 entry = ref.get();
2169 }
2170 } while (ref != null && entry == null);
2171 if (entry == null) {
2172 future = newEntry;
2173 }
2174 }
2175
2176 if (entry instanceof FieldReflector) { // check common case first
2177 return (FieldReflector) entry;
2178 } else if (entry instanceof EntryFuture) {
2179 entry = ((EntryFuture) entry).get();
2180 } else if (entry == null) {
2181 try {
2182 entry = new FieldReflector(matchFields(fields, localDesc));
2183 } catch (Throwable th) {
2184 entry = th;
2185 }
2186 future.set(entry);
2187 Caches.reflectors.put(key, new SoftReference<>(entry));
2188 }
2189
2190 if (entry instanceof FieldReflector) {
2191 return (FieldReflector) entry;
2192 } else if (entry instanceof InvalidClassException) {
2193 throw (InvalidClassException) entry;
2194 } else if (entry instanceof RuntimeException) {
2195 throw (RuntimeException) entry;
2196 } else if (entry instanceof Error) {
2197 throw (Error) entry;
2198 } else {
2199 throw new InternalError("unexpected entry: " + entry);
2200 }
2201 }
2202
2203 /**
2204 * FieldReflector cache lookup key. Keys are considered equal if they
2205 * refer to the same class and equivalent field formats.
2206 */
2207 private static class FieldReflectorKey extends WeakReference<Class<?>> {
2208
2209 private final String sigs;
2210 private final int hash;
2211 private final boolean nullClass;
2212
2213 FieldReflectorKey(Class<?> cl, ObjectStreamField[] fields,
2214 ReferenceQueue<Class<?>> queue)
2215 {
2216 super(cl, queue);
2217 nullClass = (cl == null);
2218 StringBuilder sbuf = new StringBuilder();
2219 for (int i = 0; i < fields.length; i++) {
2220 ObjectStreamField f = fields[i];
2221 sbuf.append(f.getName()).append(f.getSignature());
2222 }
2223 sigs = sbuf.toString();
2224 hash = System.identityHashCode(cl) + sigs.hashCode();
2225 }
2226
2227 public int hashCode() {
2228 return hash;
2229 }
2230
2231 public boolean equals(Object obj) {
2232 if (obj == this) {
2233 return true;
2234 }
2235
2236 if (obj instanceof FieldReflectorKey) {
2237 FieldReflectorKey other = (FieldReflectorKey) obj;
2238 Class<?> referent;
2239 return (nullClass ? other.nullClass
2240 : ((referent = get()) != null) &&
2241 (referent == other.get())) &&
2242 sigs.equals(other.sigs);
2243 } else {
2244 return false;
2245 }
2246 }
2247 }
2248
2249 /**
2250 * Matches given set of serializable fields with serializable fields
2251 * obtained from the given local class descriptor (which contain bindings
2252 * to reflective Field objects). Returns list of ObjectStreamFields in
2253 * which each ObjectStreamField whose signature matches that of a local
2254 * field contains a Field object for that field; unmatched
2255 * ObjectStreamFields contain null Field objects. Shared/unshared settings
2256 * of the returned ObjectStreamFields also reflect those of matched local
2257 * ObjectStreamFields. Throws InvalidClassException if unresolvable type
2258 * conflicts exist between the two sets of fields.
2259 */
2260 private static ObjectStreamField[] matchFields(ObjectStreamField[] fields,
2261 ObjectStreamClass localDesc)
2262 throws InvalidClassException
2263 {
2264 ObjectStreamField[] localFields = (localDesc != null) ?
2265 localDesc.fields : NO_FIELDS;
2266
2267 /*
2268 * Even if fields == localFields, we cannot simply return localFields
2269 * here. In previous implementations of serialization,
2270 * ObjectStreamField.getType() returned Object.class if the
2271 * ObjectStreamField represented a non-primitive field and belonged to
2272 * a non-local class descriptor. To preserve this (questionable)
2273 * behavior, the ObjectStreamField instances returned by matchFields
2274 * cannot report non-primitive types other than Object.class; hence
2275 * localFields cannot be returned directly.
2276 */
2277
2278 ObjectStreamField[] matches = new ObjectStreamField[fields.length];
2279 for (int i = 0; i < fields.length; i++) {
2280 ObjectStreamField f = fields[i], m = null;
2281 for (int j = 0; j < localFields.length; j++) {
2282 ObjectStreamField lf = localFields[j];
2283 if (f.getName().equals(lf.getName())) {
2284 if ((f.isPrimitive() || lf.isPrimitive()) &&
2285 f.getTypeCode() != lf.getTypeCode())
2286 {
2287 throw new InvalidClassException(localDesc.name,
2288 "incompatible types for field " + f.getName());
2289 }
2290 if (lf.getField() != null) {
2291 m = new ObjectStreamField(
2292 lf.getField(), lf.isUnshared(), false);
2293 } else {
2294 m = new ObjectStreamField(
2295 lf.getName(), lf.getSignature(), lf.isUnshared());
2296 }
2297 }
2298 }
2299 if (m == null) {
2300 m = new ObjectStreamField(
2301 f.getName(), f.getSignature(), false);
2302 }
2303 m.setOffset(f.getOffset());
2304 matches[i] = m;
2305 }
2306 return matches;
2307 }
2308
2309 /**
2310 * Removes from the specified map any keys that have been enqueued
2311 * on the specified reference queue.
2312 */
2313 static void processQueue(ReferenceQueue<Class<?>> queue,
2314 ConcurrentMap<? extends
2315 WeakReference<Class<?>>, ?> map)
2316 {
2317 Reference<? extends Class<?>> ref;
2318 while((ref = queue.poll()) != null) {
2319 map.remove(ref);
2320 }
2321 }
2322
2323 /**
2324 * Weak key for Class objects.
2325 *
2326 **/
2327 static class WeakClassKey extends WeakReference<Class<?>> {
2328 /**
2329 * saved value of the referent's identity hash code, to maintain
2330 * a consistent hash code after the referent has been cleared
2331 */
2332 private final int hash;
2333
2334 /**
2335 * Create a new WeakClassKey to the given object, registered
2336 * with a queue.
2337 */
2338 WeakClassKey(Class<?> cl, ReferenceQueue<Class<?>> refQueue) {
2339 super(cl, refQueue);
2340 hash = System.identityHashCode(cl);
2341 }
2342
2343 /**
2344 * Returns the identity hash code of the original referent.
2345 */
2346 public int hashCode() {
2347 return hash;
2348 }
2349
2350 /**
2351 * Returns true if the given object is this identical
2352 * WeakClassKey instance, or, if this object's referent has not
2353 * been cleared, if the given object is another WeakClassKey
2354 * instance with the identical non-null referent as this one.
2355 */
2356 public boolean equals(Object obj) {
2357 if (obj == this) {
2358 return true;
2359 }
2360
2361 if (obj instanceof WeakClassKey) {
2362 Object referent = get();
2363 return (referent != null) &&
2364 (referent == ((WeakClassKey) obj).get());
2365 } else {
2366 return false;
2367 }
2368 }
2369 }
2370 }