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