1 /*
2 * Copyright (c) 1996, 2022, 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.MethodHandle;
29 import java.lang.invoke.MethodHandles;
30 import java.lang.invoke.MethodType;
31 import java.lang.reflect.Constructor;
32 import java.lang.reflect.Field;
33 import java.lang.reflect.InvocationTargetException;
34 import java.lang.reflect.RecordComponent;
35 import java.lang.reflect.UndeclaredThrowableException;
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.AccessControlContext;
41 import java.security.AccessController;
42 import java.security.MessageDigest;
43 import java.security.NoSuchAlgorithmException;
44 import java.security.PermissionCollection;
45 import java.security.Permissions;
46 import java.security.PrivilegedAction;
47 import java.security.PrivilegedActionException;
48 import java.security.PrivilegedExceptionAction;
49 import java.security.ProtectionDomain;
50 import java.util.ArrayList;
51 import java.util.Arrays;
52 import java.util.Collections;
53 import java.util.Comparator;
54 import java.util.HashSet;
55 import java.util.Map;
56 import java.util.Set;
57 import java.util.concurrent.ConcurrentHashMap;
58 import jdk.internal.misc.Unsafe;
59 import jdk.internal.reflect.CallerSensitive;
60 import jdk.internal.reflect.Reflection;
61 import jdk.internal.reflect.ReflectionFactory;
62 import jdk.internal.access.SharedSecrets;
63 import jdk.internal.access.JavaSecurityAccess;
64 import sun.reflect.misc.ReflectUtil;
65
66 /**
67 * Serialization's descriptor for classes. It contains the name and
68 * serialVersionUID of the class. The ObjectStreamClass for a specific class
69 * loaded in this Java VM can be found/created using the lookup method.
70 *
71 * <p>The algorithm to compute the SerialVersionUID is described in
72 * <a href="{@docRoot}/../specs/serialization/class.html#stream-unique-identifiers">
73 * <cite>Java Object Serialization Specification,</cite> Section 4.6, "Stream Unique Identifiers"</a>.
74 *
75 * @author Mike Warres
76 * @author Roger Riggs
77 * @see ObjectStreamField
78 * @see <a href="{@docRoot}/../specs/serialization/class.html">
79 * <cite>Java Object Serialization Specification,</cite> Section 4, "Class Descriptors"</a>
80 * @since 1.1
81 */
82 public final class ObjectStreamClass implements Serializable {
83
84 /** serialPersistentFields value indicating no serializable fields */
85 public static final ObjectStreamField[] NO_FIELDS =
86 new ObjectStreamField[0];
87
88 @java.io.Serial
89 private static final long serialVersionUID = -6120832682080437368L;
90 /**
91 * {@code ObjectStreamClass} has no fields for default serialization.
92 */
93 @java.io.Serial
94 private static final ObjectStreamField[] serialPersistentFields =
95 NO_FIELDS;
96
97 /** reflection factory for obtaining serialization constructors */
98 @SuppressWarnings("removal")
99 private static final ReflectionFactory reflFactory =
100 AccessController.doPrivileged(
101 new ReflectionFactory.GetReflectionFactoryAction());
102
103 private static class Caches {
104 /** cache mapping local classes -> descriptors */
105 static final ClassCache<ObjectStreamClass> localDescs =
106 new ClassCache<>() {
107 @Override
108 protected ObjectStreamClass computeValue(Class<?> type) {
109 return new ObjectStreamClass(type);
110 }
111 };
112
113 /** cache mapping field group/local desc pairs -> field reflectors */
114 static final ClassCache<Map<FieldReflectorKey, FieldReflector>> reflectors =
115 new ClassCache<>() {
116 @Override
117 protected Map<FieldReflectorKey, FieldReflector> computeValue(Class<?> type) {
118 return new ConcurrentHashMap<>();
119 }
120 };
121 }
122
123 /** class associated with this descriptor (if any) */
124 private Class<?> cl;
125 /** name of class represented by this descriptor */
126 private String name;
127 /** serialVersionUID of represented class (null if not computed yet) */
128 private volatile Long suid;
129
130 /** true if represents dynamic proxy class */
131 private boolean isProxy;
132 /** true if represents enum type */
133 private boolean isEnum;
134 /** true if represents record type */
135 private boolean isRecord;
136 /** true if represented class implements Serializable */
137 private boolean serializable;
138 /** true if represented class implements Externalizable */
139 private boolean externalizable;
140 /** true if desc has data written by class-defined writeObject method */
141 private boolean hasWriteObjectData;
142 /**
143 * true if desc has externalizable data written in block data format; this
144 * must be true by default to accommodate ObjectInputStream subclasses which
145 * override readClassDescriptor() to return class descriptors obtained from
146 * ObjectStreamClass.lookup() (see 4461737)
147 */
148 private boolean hasBlockExternalData = true;
149
150 /**
151 * Contains information about InvalidClassException instances to be thrown
152 * when attempting operations on an invalid class. Note that instances of
153 * this class are immutable and are potentially shared among
154 * ObjectStreamClass instances.
155 */
156 private static class ExceptionInfo {
157 private final String className;
158 private final String message;
159
160 ExceptionInfo(String cn, String msg) {
161 className = cn;
162 message = msg;
163 }
164
165 /**
166 * Returns (does not throw) an InvalidClassException instance created
167 * from the information in this object, suitable for being thrown by
168 * the caller.
169 */
170 InvalidClassException newInvalidClassException() {
171 return new InvalidClassException(className, message);
172 }
173 }
174
175 /** exception (if any) thrown while attempting to resolve class */
176 private ClassNotFoundException resolveEx;
177 /** exception (if any) to throw if non-enum deserialization attempted */
178 private ExceptionInfo deserializeEx;
179 /** exception (if any) to throw if non-enum serialization attempted */
180 private ExceptionInfo serializeEx;
181 /** exception (if any) to throw if default serialization attempted */
182 private ExceptionInfo defaultSerializeEx;
183
184 /** serializable fields */
185 private ObjectStreamField[] fields;
186 /** aggregate marshalled size of primitive fields */
187 private int primDataSize;
188 /** number of non-primitive fields */
189 private int numObjFields;
190 /** reflector for setting/getting serializable field values */
191 private FieldReflector fieldRefl;
192 /** data layout of serialized objects described by this class desc */
193 private volatile ClassDataSlot[] dataLayout;
194
195 /** serialization-appropriate constructor, or null if none */
196 private Constructor<?> cons;
197 /** record canonical constructor (shared among OSCs for same class), or null */
198 private MethodHandle canonicalCtr;
199 /** cache of record deserialization constructors per unique set of stream fields
200 * (shared among OSCs for same class), or null */
201 private DeserializationConstructorsCache deserializationCtrs;
202 /** session-cache of record deserialization constructor
203 * (in de-serialized OSC only), or null */
204 private MethodHandle deserializationCtr;
205 /** protection domains that need to be checked when calling the constructor */
206 private ProtectionDomain[] domains;
207
208 /** class-defined writeObject method, or null if none */
209 private Method writeObjectMethod;
210 /** class-defined readObject method, or null if none */
211 private Method readObjectMethod;
212 /** class-defined readObjectNoData method, or null if none */
213 private Method readObjectNoDataMethod;
214 /** class-defined writeReplace method, or null if none */
215 private Method writeReplaceMethod;
216 /** class-defined readResolve method, or null if none */
217 private Method readResolveMethod;
218
219 /** local class descriptor for represented class (may point to self) */
220 private ObjectStreamClass localDesc;
221 /** superclass descriptor appearing in stream */
222 private ObjectStreamClass superDesc;
223
224 /** true if, and only if, the object has been correctly initialized */
225 private boolean initialized;
226
227 /**
228 * Initializes native code.
229 */
230 private static native void initNative();
231 static {
232 initNative();
233 }
234
235 /**
236 * Find the descriptor for a class that can be serialized. Creates an
237 * ObjectStreamClass instance if one does not exist yet for class. Null is
238 * returned if the specified class does not implement java.io.Serializable
239 * or java.io.Externalizable.
240 *
241 * @param cl class for which to get the descriptor
242 * @return the class descriptor for the specified class
243 */
244 public static ObjectStreamClass lookup(Class<?> cl) {
245 return lookup(cl, false);
246 }
247
248 /**
249 * Returns the descriptor for any class, regardless of whether it
250 * implements {@link Serializable}.
251 *
252 * @param cl class for which to get the descriptor
253 * @return the class descriptor for the specified class
254 * @since 1.6
255 */
256 public static ObjectStreamClass lookupAny(Class<?> cl) {
257 return lookup(cl, true);
258 }
259
260 /**
261 * Returns the name of the class described by this descriptor.
262 * This method returns the name of the class in the format that
263 * is used by the {@link Class#getName} method.
264 *
265 * @return a string representing the name of the class
266 */
267 public String getName() {
268 return name;
269 }
270
271 /**
272 * Return the serialVersionUID for this class. The serialVersionUID
273 * defines a set of classes all with the same name that have evolved from a
274 * common root class and agree to be serialized and deserialized using a
275 * common format. NonSerializable classes have a serialVersionUID of 0L.
276 *
277 * @return the SUID of the class described by this descriptor
278 */
279 @SuppressWarnings("removal")
280 public long getSerialVersionUID() {
281 // REMIND: synchronize instead of relying on volatile?
282 if (suid == null) {
283 if (isRecord)
284 return 0L;
285
286 suid = AccessController.doPrivileged(
287 new PrivilegedAction<Long>() {
288 public Long run() {
289 return computeDefaultSUID(cl);
290 }
291 }
292 );
293 }
294 return suid.longValue();
295 }
296
297 /**
298 * Return the class in the local VM that this version is mapped to. Null
299 * is returned if there is no corresponding local class.
300 *
301 * @return the {@code Class} instance that this descriptor represents
302 */
303 @SuppressWarnings("removal")
304 @CallerSensitive
305 public Class<?> forClass() {
306 if (cl == null) {
307 return null;
308 }
309 requireInitialized();
310 if (System.getSecurityManager() != null) {
311 Class<?> caller = Reflection.getCallerClass();
312 if (ReflectUtil.needsPackageAccessCheck(caller.getClassLoader(), cl.getClassLoader())) {
313 ReflectUtil.checkPackageAccess(cl);
314 }
315 }
316 return cl;
317 }
318
319 /**
320 * Return an array of the fields of this serializable class.
321 *
322 * @return an array containing an element for each persistent field of
323 * this class. Returns an array of length zero if there are no
324 * fields.
325 * @since 1.2
326 */
327 public ObjectStreamField[] getFields() {
328 return getFields(true);
329 }
330
331 /**
332 * Get the field of this class by name.
333 *
334 * @param name the name of the data field to look for
335 * @return The ObjectStreamField object of the named field or null if
336 * there is no such named field.
337 */
338 public ObjectStreamField getField(String name) {
339 return getField(name, null);
340 }
341
342 /**
343 * Return a string describing this ObjectStreamClass.
344 */
345 public String toString() {
346 return name + ": static final long serialVersionUID = " +
347 getSerialVersionUID() + "L;";
348 }
349
350 /**
351 * Looks up and returns class descriptor for given class, or null if class
352 * is non-serializable and "all" is set to false.
353 *
354 * @param cl class to look up
355 * @param all if true, return descriptors for all classes; if false, only
356 * return descriptors for serializable classes
357 */
358 static ObjectStreamClass lookup(Class<?> cl, boolean all) {
359 if (!(all || Serializable.class.isAssignableFrom(cl))) {
360 return null;
361 }
362 return Caches.localDescs.get(cl);
363 }
364
365 /**
366 * Creates local class descriptor representing given class.
367 */
368 @SuppressWarnings("removal")
369 private ObjectStreamClass(final Class<?> cl) {
370 this.cl = cl;
371 name = cl.getName();
372 isProxy = Proxy.isProxyClass(cl);
373 isEnum = Enum.class.isAssignableFrom(cl);
374 isRecord = cl.isRecord();
375 serializable = Serializable.class.isAssignableFrom(cl);
376 externalizable = Externalizable.class.isAssignableFrom(cl);
377
378 Class<?> superCl = cl.getSuperclass();
379 superDesc = (superCl != null) ? lookup(superCl, false) : null;
380 localDesc = this;
381
382 if (serializable) {
383 AccessController.doPrivileged(new PrivilegedAction<>() {
384 public Void run() {
385 if (isEnum) {
386 suid = 0L;
387 fields = NO_FIELDS;
388 return null;
389 }
390 if (cl.isArray()) {
391 fields = NO_FIELDS;
392 return null;
393 }
394
395 suid = getDeclaredSUID(cl);
396 try {
397 fields = getSerialFields(cl);
398 computeFieldOffsets();
399 } catch (InvalidClassException e) {
400 serializeEx = deserializeEx =
401 new ExceptionInfo(e.classname, e.getMessage());
402 fields = NO_FIELDS;
403 }
404
405 if (isRecord) {
406 canonicalCtr = canonicalRecordCtr(cl);
407 deserializationCtrs = new DeserializationConstructorsCache();
408 } else if (externalizable) {
409 cons = getExternalizableConstructor(cl);
410 } else {
411 cons = getSerializableConstructor(cl);
412 writeObjectMethod = getPrivateMethod(cl, "writeObject",
413 new Class<?>[] { ObjectOutputStream.class },
414 Void.TYPE);
415 readObjectMethod = getPrivateMethod(cl, "readObject",
416 new Class<?>[] { ObjectInputStream.class },
417 Void.TYPE);
418 readObjectNoDataMethod = getPrivateMethod(
419 cl, "readObjectNoData", null, Void.TYPE);
420 hasWriteObjectData = (writeObjectMethod != null);
421 }
422 domains = getProtectionDomains(cons, cl);
423 writeReplaceMethod = getInheritableMethod(
424 cl, "writeReplace", null, Object.class);
425 readResolveMethod = getInheritableMethod(
426 cl, "readResolve", null, Object.class);
427 return null;
428 }
429 });
430 } else {
431 suid = 0L;
432 fields = NO_FIELDS;
433 }
434
435 try {
436 fieldRefl = getReflector(fields, this);
437 } catch (InvalidClassException ex) {
438 // field mismatches impossible when matching local fields vs. self
439 throw new InternalError(ex);
440 }
441
442 if (deserializeEx == null) {
443 if (isEnum) {
444 deserializeEx = new ExceptionInfo(name, "enum type");
445 } else if (cons == null && !isRecord) {
446 deserializeEx = new ExceptionInfo(name, "no valid constructor");
447 }
448 }
449 if (isRecord && canonicalCtr == null) {
450 deserializeEx = new ExceptionInfo(name, "record canonical constructor not found");
451 } else {
452 for (int i = 0; i < fields.length; i++) {
453 if (fields[i].getField() == null) {
454 defaultSerializeEx = new ExceptionInfo(
455 name, "unmatched serializable field(s) declared");
456 }
457 }
458 }
459 initialized = true;
460 }
461
462 /**
463 * Creates blank class descriptor which should be initialized via a
464 * subsequent call to initProxy(), initNonProxy() or readNonProxy().
465 */
466 ObjectStreamClass() {
467 }
468
469 /**
470 * Creates a PermissionDomain that grants no permission.
471 */
472 private ProtectionDomain noPermissionsDomain() {
473 PermissionCollection perms = new Permissions();
474 perms.setReadOnly();
475 return new ProtectionDomain(null, perms);
476 }
477
478 /**
479 * Aggregate the ProtectionDomains of all the classes that separate
480 * a concrete class {@code cl} from its ancestor's class declaring
481 * a constructor {@code cons}.
482 *
483 * If {@code cl} is defined by the boot loader, or the constructor
484 * {@code cons} is declared by {@code cl}, or if there is no security
485 * manager, then this method does nothing and {@code null} is returned.
486 *
487 * @param cons A constructor declared by {@code cl} or one of its
488 * ancestors.
489 * @param cl A concrete class, which is either the class declaring
490 * the constructor {@code cons}, or a serializable subclass
491 * of that class.
492 * @return An array of ProtectionDomain representing the set of
493 * ProtectionDomain that separate the concrete class {@code cl}
494 * from its ancestor's declaring {@code cons}, or {@code null}.
495 */
496 @SuppressWarnings("removal")
497 private ProtectionDomain[] getProtectionDomains(Constructor<?> cons,
498 Class<?> cl) {
499 ProtectionDomain[] domains = null;
500 if (cons != null && cl.getClassLoader() != null
501 && System.getSecurityManager() != null) {
502 Class<?> cls = cl;
503 Class<?> fnscl = cons.getDeclaringClass();
504 Set<ProtectionDomain> pds = null;
505 while (cls != fnscl) {
506 ProtectionDomain pd = cls.getProtectionDomain();
507 if (pd != null) {
508 if (pds == null) pds = new HashSet<>();
509 pds.add(pd);
510 }
511 cls = cls.getSuperclass();
512 if (cls == null) {
513 // that's not supposed to happen
514 // make a ProtectionDomain with no permission.
515 // should we throw instead?
516 if (pds == null) pds = new HashSet<>();
517 else pds.clear();
518 pds.add(noPermissionsDomain());
519 break;
520 }
521 }
522 if (pds != null) {
523 domains = pds.toArray(new ProtectionDomain[0]);
524 }
525 }
526 return domains;
527 }
528
529 /**
530 * Initializes class descriptor representing a proxy class.
531 */
532 void initProxy(Class<?> cl,
533 ClassNotFoundException resolveEx,
534 ObjectStreamClass superDesc)
535 throws InvalidClassException
536 {
537 ObjectStreamClass osc = null;
538 if (cl != null) {
539 osc = lookup(cl, true);
540 if (!osc.isProxy) {
541 throw new InvalidClassException(
542 "cannot bind proxy descriptor to a non-proxy class");
543 }
544 }
545 this.cl = cl;
546 this.resolveEx = resolveEx;
547 this.superDesc = superDesc;
548 isProxy = true;
549 serializable = true;
550 suid = 0L;
551 fields = NO_FIELDS;
552 if (osc != null) {
553 localDesc = osc;
554 name = localDesc.name;
555 externalizable = localDesc.externalizable;
556 writeReplaceMethod = localDesc.writeReplaceMethod;
557 readResolveMethod = localDesc.readResolveMethod;
558 deserializeEx = localDesc.deserializeEx;
559 domains = localDesc.domains;
560 cons = localDesc.cons;
561 }
562 fieldRefl = getReflector(fields, localDesc);
563 initialized = true;
564 }
565
566 /**
567 * Initializes class descriptor representing a non-proxy class.
568 */
569 void initNonProxy(ObjectStreamClass model,
570 Class<?> cl,
571 ClassNotFoundException resolveEx,
572 ObjectStreamClass superDesc)
573 throws InvalidClassException
574 {
575 long suid = model.getSerialVersionUID();
576 ObjectStreamClass osc = null;
577 if (cl != null) {
578 osc = lookup(cl, true);
579 if (osc.isProxy) {
580 throw new InvalidClassException(
581 "cannot bind non-proxy descriptor to a proxy class");
582 }
583 if (model.isEnum != osc.isEnum) {
584 throw new InvalidClassException(model.isEnum ?
585 "cannot bind enum descriptor to a non-enum class" :
586 "cannot bind non-enum descriptor to an enum class");
587 }
588
589 if (model.serializable == osc.serializable &&
590 !cl.isArray() && !cl.isRecord() &&
591 suid != osc.getSerialVersionUID()) {
592 throw new InvalidClassException(osc.name,
593 "local class incompatible: " +
594 "stream classdesc serialVersionUID = " + suid +
595 ", local class serialVersionUID = " +
596 osc.getSerialVersionUID());
597 }
598
599 if (!classNamesEqual(model.name, osc.name)) {
600 throw new InvalidClassException(osc.name,
601 "local class name incompatible with stream class " +
602 "name \"" + model.name + "\"");
603 }
604
605 if (!model.isEnum) {
606 if ((model.serializable == osc.serializable) &&
607 (model.externalizable != osc.externalizable)) {
608 throw new InvalidClassException(osc.name,
609 "Serializable incompatible with Externalizable");
610 }
611
612 if ((model.serializable != osc.serializable) ||
613 (model.externalizable != osc.externalizable) ||
614 !(model.serializable || model.externalizable)) {
615 deserializeEx = new ExceptionInfo(
616 osc.name, "class invalid for deserialization");
617 }
618 }
619 }
620
621 this.cl = cl;
622 this.resolveEx = resolveEx;
623 this.superDesc = superDesc;
624 name = model.name;
625 this.suid = suid;
626 isProxy = false;
627 isEnum = model.isEnum;
628 serializable = model.serializable;
629 externalizable = model.externalizable;
630 hasBlockExternalData = model.hasBlockExternalData;
631 hasWriteObjectData = model.hasWriteObjectData;
632 fields = model.fields;
633 primDataSize = model.primDataSize;
634 numObjFields = model.numObjFields;
635
636 if (osc != null) {
637 localDesc = osc;
638 isRecord = localDesc.isRecord;
639 // canonical record constructor is shared
640 canonicalCtr = localDesc.canonicalCtr;
641 // cache of deserialization constructors is shared
642 deserializationCtrs = localDesc.deserializationCtrs;
643 writeObjectMethod = localDesc.writeObjectMethod;
644 readObjectMethod = localDesc.readObjectMethod;
645 readObjectNoDataMethod = localDesc.readObjectNoDataMethod;
646 writeReplaceMethod = localDesc.writeReplaceMethod;
647 readResolveMethod = localDesc.readResolveMethod;
648 if (deserializeEx == null) {
649 deserializeEx = localDesc.deserializeEx;
650 }
651 domains = localDesc.domains;
652 assert cl.isRecord() ? localDesc.cons == null : true;
653 cons = localDesc.cons;
654 }
655
656 fieldRefl = getReflector(fields, localDesc);
657 // reassign to matched fields so as to reflect local unshared settings
658 fields = fieldRefl.getFields();
659
660 initialized = true;
661 }
662
663 /**
664 * Reads non-proxy class descriptor information from given input stream.
665 * The resulting class descriptor is not fully functional; it can only be
666 * used as input to the ObjectInputStream.resolveClass() and
667 * ObjectStreamClass.initNonProxy() methods.
668 */
669 void readNonProxy(ObjectInputStream in)
670 throws IOException, ClassNotFoundException
671 {
672 name = in.readUTF();
673 suid = in.readLong();
674 isProxy = false;
675
676 byte flags = in.readByte();
677 hasWriteObjectData =
678 ((flags & ObjectStreamConstants.SC_WRITE_METHOD) != 0);
679 hasBlockExternalData =
680 ((flags & ObjectStreamConstants.SC_BLOCK_DATA) != 0);
681 externalizable =
682 ((flags & ObjectStreamConstants.SC_EXTERNALIZABLE) != 0);
683 boolean sflag =
684 ((flags & ObjectStreamConstants.SC_SERIALIZABLE) != 0);
685 if (externalizable && sflag) {
686 throw new InvalidClassException(
687 name, "serializable and externalizable flags conflict");
688 }
689 serializable = externalizable || sflag;
690 isEnum = ((flags & ObjectStreamConstants.SC_ENUM) != 0);
691 if (isEnum && suid.longValue() != 0L) {
692 throw new InvalidClassException(name,
693 "enum descriptor has non-zero serialVersionUID: " + suid);
694 }
695
696 int numFields = in.readShort();
697 if (isEnum && numFields != 0) {
698 throw new InvalidClassException(name,
699 "enum descriptor has non-zero field count: " + numFields);
700 }
701 fields = (numFields > 0) ?
702 new ObjectStreamField[numFields] : NO_FIELDS;
703 for (int i = 0; i < numFields; i++) {
704 char tcode = (char) in.readByte();
705 String fname = in.readUTF();
706 String signature = ((tcode == 'L') || (tcode == '[')) ?
707 in.readTypeString() : String.valueOf(tcode);
708 try {
709 fields[i] = new ObjectStreamField(fname, signature, false);
710 } catch (RuntimeException e) {
711 throw new InvalidClassException(name,
712 "invalid descriptor for field " +
713 fname, e);
714 }
715 }
716 computeFieldOffsets();
717 }
718
719 /**
720 * Writes non-proxy class descriptor information to given output stream.
721 */
722 void writeNonProxy(ObjectOutputStream out) throws IOException {
723 out.writeUTF(name);
724 out.writeLong(getSerialVersionUID());
725
726 byte flags = 0;
727 if (externalizable) {
728 flags |= ObjectStreamConstants.SC_EXTERNALIZABLE;
729 int protocol = out.getProtocolVersion();
730 if (protocol != ObjectStreamConstants.PROTOCOL_VERSION_1) {
731 flags |= ObjectStreamConstants.SC_BLOCK_DATA;
732 }
733 } else if (serializable) {
734 flags |= ObjectStreamConstants.SC_SERIALIZABLE;
735 }
736 if (hasWriteObjectData) {
737 flags |= ObjectStreamConstants.SC_WRITE_METHOD;
738 }
739 if (isEnum) {
740 flags |= ObjectStreamConstants.SC_ENUM;
741 }
742 out.writeByte(flags);
743
744 out.writeShort(fields.length);
745 for (int i = 0; i < fields.length; i++) {
746 ObjectStreamField f = fields[i];
747 out.writeByte(f.getTypeCode());
748 out.writeUTF(f.getName());
749 if (!f.isPrimitive()) {
750 out.writeTypeString(f.getTypeString());
751 }
752 }
753 }
754
755 /**
756 * Returns ClassNotFoundException (if any) thrown while attempting to
757 * resolve local class corresponding to this class descriptor.
758 */
759 ClassNotFoundException getResolveException() {
760 return resolveEx;
761 }
762
763 /**
764 * Throws InternalError if not initialized.
765 */
766 private final void requireInitialized() {
767 if (!initialized)
768 throw new InternalError("Unexpected call when not initialized");
769 }
770
771 /**
772 * Throws InvalidClassException if not initialized.
773 * To be called in cases where an uninitialized class descriptor indicates
774 * a problem in the serialization stream.
775 */
776 final void checkInitialized() throws InvalidClassException {
777 if (!initialized) {
778 throw new InvalidClassException("Class descriptor should be initialized");
779 }
780 }
781
782 /**
783 * Throws an InvalidClassException if object instances referencing this
784 * class descriptor should not be allowed to deserialize. This method does
785 * not apply to deserialization of enum constants.
786 */
787 void checkDeserialize() throws InvalidClassException {
788 requireInitialized();
789 if (deserializeEx != null) {
790 throw deserializeEx.newInvalidClassException();
791 }
792 }
793
794 /**
795 * Throws an InvalidClassException if objects whose class is represented by
796 * this descriptor should not be allowed to serialize. This method does
797 * not apply to serialization of enum constants.
798 */
799 void checkSerialize() throws InvalidClassException {
800 requireInitialized();
801 if (serializeEx != null) {
802 throw serializeEx.newInvalidClassException();
803 }
804 }
805
806 /**
807 * Throws an InvalidClassException if objects whose class is represented by
808 * this descriptor should not be permitted to use default serialization
809 * (e.g., if the class declares serializable fields that do not correspond
810 * to actual fields, and hence must use the GetField API). This method
811 * does not apply to deserialization of enum constants.
812 */
813 void checkDefaultSerialize() throws InvalidClassException {
814 requireInitialized();
815 if (defaultSerializeEx != null) {
816 throw defaultSerializeEx.newInvalidClassException();
817 }
818 }
819
820 /**
821 * Returns superclass descriptor. Note that on the receiving side, the
822 * superclass descriptor may be bound to a class that is not a superclass
823 * of the subclass descriptor's bound class.
824 */
825 ObjectStreamClass getSuperDesc() {
826 requireInitialized();
827 return superDesc;
828 }
829
830 /**
831 * Returns the "local" class descriptor for the class associated with this
832 * class descriptor (i.e., the result of
833 * ObjectStreamClass.lookup(this.forClass())) or null if there is no class
834 * associated with this descriptor.
835 */
836 ObjectStreamClass getLocalDesc() {
837 requireInitialized();
838 return localDesc;
839 }
840
841 /**
842 * Returns arrays of ObjectStreamFields representing the serializable
843 * fields of the represented class. If copy is true, a clone of this class
844 * descriptor's field array is returned, otherwise the array itself is
845 * returned.
846 */
847 ObjectStreamField[] getFields(boolean copy) {
848 return copy ? fields.clone() : fields;
849 }
850
851 /**
852 * Looks up a serializable field of the represented class by name and type.
853 * A specified type of null matches all types, Object.class matches all
854 * non-primitive types, and any other non-null type matches assignable
855 * types only. Returns matching field, or null if no match found.
856 */
857 ObjectStreamField getField(String name, Class<?> type) {
858 for (int i = 0; i < fields.length; i++) {
859 ObjectStreamField f = fields[i];
860 if (f.getName().equals(name)) {
861 if (type == null ||
862 (type == Object.class && !f.isPrimitive()))
863 {
864 return f;
865 }
866 Class<?> ftype = f.getType();
867 if (ftype != null && type.isAssignableFrom(ftype)) {
868 return f;
869 }
870 }
871 }
872 return null;
873 }
874
875 /**
876 * Returns true if class descriptor represents a dynamic proxy class, false
877 * otherwise.
878 */
879 boolean isProxy() {
880 requireInitialized();
881 return isProxy;
882 }
883
884 /**
885 * Returns true if class descriptor represents an enum type, false
886 * otherwise.
887 */
888 boolean isEnum() {
889 requireInitialized();
890 return isEnum;
891 }
892
893 /**
894 * Returns true if class descriptor represents a record type, false
895 * otherwise.
896 */
897 boolean isRecord() {
898 requireInitialized();
899 return isRecord;
900 }
901
902 /**
903 * Returns true if represented class implements Externalizable, false
904 * otherwise.
905 */
906 boolean isExternalizable() {
907 requireInitialized();
908 return externalizable;
909 }
910
911 /**
912 * Returns true if represented class implements Serializable, false
913 * otherwise.
914 */
915 boolean isSerializable() {
916 requireInitialized();
917 return serializable;
918 }
919
920 /**
921 * Returns true if class descriptor represents externalizable class that
922 * has written its data in 1.2 (block data) format, false otherwise.
923 */
924 boolean hasBlockExternalData() {
925 requireInitialized();
926 return hasBlockExternalData;
927 }
928
929 /**
930 * Returns true if class descriptor represents serializable (but not
931 * externalizable) class which has written its data via a custom
932 * writeObject() method, false otherwise.
933 */
934 boolean hasWriteObjectData() {
935 requireInitialized();
936 return hasWriteObjectData;
937 }
938
939 /**
940 * Returns true if represented class is serializable/externalizable and can
941 * be instantiated by the serialization runtime--i.e., if it is
942 * externalizable and defines a public no-arg constructor, or if it is
943 * non-externalizable and its first non-serializable superclass defines an
944 * accessible no-arg constructor. Otherwise, returns false.
945 */
946 boolean isInstantiable() {
947 requireInitialized();
948 return (cons != null);
949 }
950
951 /**
952 * Returns true if represented class is serializable (but not
953 * externalizable) and defines a conformant writeObject method. Otherwise,
954 * returns false.
955 */
956 boolean hasWriteObjectMethod() {
957 requireInitialized();
958 return (writeObjectMethod != null);
959 }
960
961 /**
962 * Returns true if represented class is serializable (but not
963 * externalizable) and defines a conformant readObject method. Otherwise,
964 * returns false.
965 */
966 boolean hasReadObjectMethod() {
967 requireInitialized();
968 return (readObjectMethod != null);
969 }
970
971 /**
972 * Returns true if represented class is serializable (but not
973 * externalizable) and defines a conformant readObjectNoData method.
974 * Otherwise, returns false.
975 */
976 boolean hasReadObjectNoDataMethod() {
977 requireInitialized();
978 return (readObjectNoDataMethod != null);
979 }
980
981 /**
982 * Returns true if represented class is serializable or externalizable and
983 * defines a conformant writeReplace method. Otherwise, returns false.
984 */
985 boolean hasWriteReplaceMethod() {
986 requireInitialized();
987 return (writeReplaceMethod != null);
988 }
989
990 /**
991 * Returns true if represented class is serializable or externalizable and
992 * defines a conformant readResolve method. Otherwise, returns false.
993 */
994 boolean hasReadResolveMethod() {
995 requireInitialized();
996 return (readResolveMethod != null);
997 }
998
999 /**
1000 * Creates a new instance of the represented class. If the class is
1001 * externalizable, invokes its public no-arg constructor; otherwise, if the
1002 * class is serializable, invokes the no-arg constructor of the first
1003 * non-serializable superclass. Throws UnsupportedOperationException if
1004 * this class descriptor is not associated with a class, if the associated
1005 * class is non-serializable or if the appropriate no-arg constructor is
1006 * inaccessible/unavailable.
1007 */
1008 @SuppressWarnings("removal")
1009 Object newInstance()
1010 throws InstantiationException, InvocationTargetException,
1011 UnsupportedOperationException
1012 {
1013 requireInitialized();
1014 if (cons != null) {
1015 try {
1016 if (domains == null || domains.length == 0) {
1017 return cons.newInstance();
1018 } else {
1019 JavaSecurityAccess jsa = SharedSecrets.getJavaSecurityAccess();
1020 PrivilegedAction<?> pea = () -> {
1021 try {
1022 return cons.newInstance();
1023 } catch (InstantiationException
1024 | InvocationTargetException
1025 | IllegalAccessException x) {
1026 throw new UndeclaredThrowableException(x);
1027 }
1028 }; // Can't use PrivilegedExceptionAction with jsa
1029 try {
1030 return jsa.doIntersectionPrivilege(pea,
1031 AccessController.getContext(),
1032 new AccessControlContext(domains));
1033 } catch (UndeclaredThrowableException x) {
1034 Throwable cause = x.getCause();
1035 if (cause instanceof InstantiationException)
1036 throw (InstantiationException) cause;
1037 if (cause instanceof InvocationTargetException)
1038 throw (InvocationTargetException) cause;
1039 if (cause instanceof IllegalAccessException)
1040 throw (IllegalAccessException) cause;
1041 // not supposed to happen
1042 throw x;
1043 }
1044 }
1045 } catch (IllegalAccessException ex) {
1046 // should not occur, as access checks have been suppressed
1047 throw new InternalError(ex);
1048 } catch (InstantiationError err) {
1049 var ex = new InstantiationException();
1050 ex.initCause(err);
1051 throw ex;
1052 }
1053 } else {
1054 throw new UnsupportedOperationException();
1055 }
1056 }
1057
1058 /**
1059 * Invokes the writeObject method of the represented serializable class.
1060 * Throws UnsupportedOperationException if this class descriptor is not
1061 * associated with a class, or if the class is externalizable,
1062 * non-serializable or does not define writeObject.
1063 */
1064 void invokeWriteObject(Object obj, ObjectOutputStream out)
1065 throws IOException, UnsupportedOperationException
1066 {
1067 requireInitialized();
1068 if (writeObjectMethod != null) {
1069 try {
1070 writeObjectMethod.invoke(obj, new Object[]{ out });
1071 } catch (InvocationTargetException ex) {
1072 Throwable th = ex.getCause();
1073 if (th instanceof IOException) {
1074 throw (IOException) th;
1075 } else {
1076 throwMiscException(th);
1077 }
1078 } catch (IllegalAccessException ex) {
1079 // should not occur, as access checks have been suppressed
1080 throw new InternalError(ex);
1081 }
1082 } else {
1083 throw new UnsupportedOperationException();
1084 }
1085 }
1086
1087 /**
1088 * Invokes the readObject method of the represented serializable class.
1089 * Throws UnsupportedOperationException if this class descriptor is not
1090 * associated with a class, or if the class is externalizable,
1091 * non-serializable or does not define readObject.
1092 */
1093 void invokeReadObject(Object obj, ObjectInputStream in)
1094 throws ClassNotFoundException, IOException,
1095 UnsupportedOperationException
1096 {
1097 requireInitialized();
1098 if (readObjectMethod != null) {
1099 try {
1100 readObjectMethod.invoke(obj, new Object[]{ in });
1101 } catch (InvocationTargetException ex) {
1102 Throwable th = ex.getCause();
1103 if (th instanceof ClassNotFoundException) {
1104 throw (ClassNotFoundException) th;
1105 } else if (th instanceof IOException) {
1106 throw (IOException) th;
1107 } else {
1108 throwMiscException(th);
1109 }
1110 } catch (IllegalAccessException ex) {
1111 // should not occur, as access checks have been suppressed
1112 throw new InternalError(ex);
1113 }
1114 } else {
1115 throw new UnsupportedOperationException();
1116 }
1117 }
1118
1119 /**
1120 * Invokes the readObjectNoData method of the represented serializable
1121 * class. Throws UnsupportedOperationException if this class descriptor is
1122 * not associated with a class, or if the class is externalizable,
1123 * non-serializable or does not define readObjectNoData.
1124 */
1125 void invokeReadObjectNoData(Object obj)
1126 throws IOException, UnsupportedOperationException
1127 {
1128 requireInitialized();
1129 if (readObjectNoDataMethod != null) {
1130 try {
1131 readObjectNoDataMethod.invoke(obj, (Object[]) null);
1132 } catch (InvocationTargetException ex) {
1133 Throwable th = ex.getCause();
1134 if (th instanceof ObjectStreamException) {
1135 throw (ObjectStreamException) th;
1136 } else {
1137 throwMiscException(th);
1138 }
1139 } catch (IllegalAccessException ex) {
1140 // should not occur, as access checks have been suppressed
1141 throw new InternalError(ex);
1142 }
1143 } else {
1144 throw new UnsupportedOperationException();
1145 }
1146 }
1147
1148 /**
1149 * Invokes the writeReplace method of the represented serializable class and
1150 * returns the result. Throws UnsupportedOperationException if this class
1151 * descriptor is not associated with a class, or if the class is
1152 * non-serializable or does not define writeReplace.
1153 */
1154 Object invokeWriteReplace(Object obj)
1155 throws IOException, UnsupportedOperationException
1156 {
1157 requireInitialized();
1158 if (writeReplaceMethod != null) {
1159 try {
1160 return writeReplaceMethod.invoke(obj, (Object[]) null);
1161 } catch (InvocationTargetException ex) {
1162 Throwable th = ex.getCause();
1163 if (th instanceof ObjectStreamException) {
1164 throw (ObjectStreamException) th;
1165 } else {
1166 throwMiscException(th);
1167 throw new InternalError(th); // never reached
1168 }
1169 } catch (IllegalAccessException ex) {
1170 // should not occur, as access checks have been suppressed
1171 throw new InternalError(ex);
1172 }
1173 } else {
1174 throw new UnsupportedOperationException();
1175 }
1176 }
1177
1178 /**
1179 * Invokes the readResolve method of the represented serializable class and
1180 * returns the result. Throws UnsupportedOperationException if this class
1181 * descriptor is not associated with a class, or if the class is
1182 * non-serializable or does not define readResolve.
1183 */
1184 Object invokeReadResolve(Object obj)
1185 throws IOException, UnsupportedOperationException
1186 {
1187 requireInitialized();
1188 if (readResolveMethod != null) {
1189 try {
1190 return readResolveMethod.invoke(obj, (Object[]) null);
1191 } catch (InvocationTargetException ex) {
1192 Throwable th = ex.getCause();
1193 if (th instanceof ObjectStreamException) {
1194 throw (ObjectStreamException) th;
1195 } else {
1196 throwMiscException(th);
1197 throw new InternalError(th); // never reached
1198 }
1199 } catch (IllegalAccessException ex) {
1200 // should not occur, as access checks have been suppressed
1201 throw new InternalError(ex);
1202 }
1203 } else {
1204 throw new UnsupportedOperationException();
1205 }
1206 }
1207
1208 /**
1209 * Class representing the portion of an object's serialized form allotted
1210 * to data described by a given class descriptor. If "hasData" is false,
1211 * the object's serialized form does not contain data associated with the
1212 * class descriptor.
1213 */
1214 static class ClassDataSlot {
1215
1216 /** class descriptor "occupying" this slot */
1217 final ObjectStreamClass desc;
1218 /** true if serialized form includes data for this slot's descriptor */
1219 final boolean hasData;
1220
1221 ClassDataSlot(ObjectStreamClass desc, boolean hasData) {
1222 this.desc = desc;
1223 this.hasData = hasData;
1224 }
1225 }
1226
1227 /**
1228 * Returns array of ClassDataSlot instances representing the data layout
1229 * (including superclass data) for serialized objects described by this
1230 * class descriptor. ClassDataSlots are ordered by inheritance with those
1231 * containing "higher" superclasses appearing first. The final
1232 * ClassDataSlot contains a reference to this descriptor.
1233 */
1234 ClassDataSlot[] getClassDataLayout() throws InvalidClassException {
1235 // REMIND: synchronize instead of relying on volatile?
1236 if (dataLayout == null) {
1237 dataLayout = getClassDataLayout0();
1238 }
1239 return dataLayout;
1240 }
1241
1242 private ClassDataSlot[] getClassDataLayout0()
1243 throws InvalidClassException
1244 {
1245 ArrayList<ClassDataSlot> slots = new ArrayList<>();
1246 Class<?> start = cl, end = cl;
1247
1248 // locate closest non-serializable superclass
1249 while (end != null && Serializable.class.isAssignableFrom(end)) {
1250 end = end.getSuperclass();
1251 }
1252
1253 HashSet<String> oscNames = new HashSet<>(3);
1254
1255 for (ObjectStreamClass d = this; d != null; d = d.superDesc) {
1256 if (oscNames.contains(d.name)) {
1257 throw new InvalidClassException("Circular reference.");
1258 } else {
1259 oscNames.add(d.name);
1260 }
1261
1262 // search up inheritance hierarchy for class with matching name
1263 String searchName = (d.cl != null) ? d.cl.getName() : d.name;
1264 Class<?> match = null;
1265 for (Class<?> c = start; c != end; c = c.getSuperclass()) {
1266 if (searchName.equals(c.getName())) {
1267 match = c;
1268 break;
1269 }
1270 }
1271
1272 // add "no data" slot for each unmatched class below match
1273 if (match != null) {
1274 for (Class<?> c = start; c != match; c = c.getSuperclass()) {
1275 slots.add(new ClassDataSlot(
1276 ObjectStreamClass.lookup(c, true), false));
1277 }
1278 start = match.getSuperclass();
1279 }
1280
1281 // record descriptor/class pairing
1282 slots.add(new ClassDataSlot(d.getVariantFor(match), true));
1283 }
1284
1285 // add "no data" slot for any leftover unmatched classes
1286 for (Class<?> c = start; c != end; c = c.getSuperclass()) {
1287 slots.add(new ClassDataSlot(
1288 ObjectStreamClass.lookup(c, true), false));
1289 }
1290
1291 // order slots from superclass -> subclass
1292 Collections.reverse(slots);
1293 return slots.toArray(new ClassDataSlot[slots.size()]);
1294 }
1295
1296 /**
1297 * Returns aggregate size (in bytes) of marshalled primitive field values
1298 * for represented class.
1299 */
1300 int getPrimDataSize() {
1301 return primDataSize;
1302 }
1303
1304 /**
1305 * Returns number of non-primitive serializable fields of represented
1306 * class.
1307 */
1308 int getNumObjFields() {
1309 return numObjFields;
1310 }
1311
1312 /**
1313 * Fetches the serializable primitive field values of object obj and
1314 * marshals them into byte array buf starting at offset 0. It is the
1315 * responsibility of the caller to ensure that obj is of the proper type if
1316 * non-null.
1317 */
1318 void getPrimFieldValues(Object obj, byte[] buf) {
1319 fieldRefl.getPrimFieldValues(obj, buf);
1320 }
1321
1322 /**
1323 * Sets the serializable primitive fields of object obj using values
1324 * unmarshalled from byte array buf starting at offset 0. It is the
1325 * responsibility of the caller to ensure that obj is of the proper type if
1326 * non-null.
1327 */
1328 void setPrimFieldValues(Object obj, byte[] buf) {
1329 fieldRefl.setPrimFieldValues(obj, buf);
1330 }
1331
1332 /**
1333 * Fetches the serializable object field values of object obj and stores
1334 * them in array vals starting at offset 0. It is the responsibility of
1335 * the caller to ensure that obj is of the proper type if non-null.
1336 */
1337 void getObjFieldValues(Object obj, Object[] vals) {
1338 fieldRefl.getObjFieldValues(obj, vals);
1339 }
1340
1341 /**
1342 * Checks that the given values, from array vals starting at offset 0,
1343 * are assignable to the given serializable object fields.
1344 * @throws ClassCastException if any value is not assignable
1345 */
1346 void checkObjFieldValueTypes(Object obj, Object[] vals) {
1347 fieldRefl.checkObjectFieldValueTypes(obj, vals);
1348 }
1349
1350 /**
1351 * Sets the serializable object fields of object obj using values from
1352 * array vals starting at offset 0. It is the responsibility of the caller
1353 * to ensure that obj is of the proper type if non-null.
1354 */
1355 void setObjFieldValues(Object obj, Object[] vals) {
1356 fieldRefl.setObjFieldValues(obj, vals);
1357 }
1358
1359 /**
1360 * Calculates and sets serializable field offsets, as well as primitive
1361 * data size and object field count totals. Throws InvalidClassException
1362 * if fields are illegally ordered.
1363 */
1364 private void computeFieldOffsets() throws InvalidClassException {
1365 primDataSize = 0;
1366 numObjFields = 0;
1367 int firstObjIndex = -1;
1368
1369 for (int i = 0; i < fields.length; i++) {
1370 ObjectStreamField f = fields[i];
1371 switch (f.getTypeCode()) {
1372 case 'Z', 'B' -> f.setOffset(primDataSize++);
1373 case 'C', 'S' -> {
1374 f.setOffset(primDataSize);
1375 primDataSize += 2;
1376 }
1377 case 'I', 'F' -> {
1378 f.setOffset(primDataSize);
1379 primDataSize += 4;
1380 }
1381 case 'J', 'D' -> {
1382 f.setOffset(primDataSize);
1383 primDataSize += 8;
1384 }
1385 case '[', 'L' -> {
1386 f.setOffset(numObjFields++);
1387 if (firstObjIndex == -1) {
1388 firstObjIndex = i;
1389 }
1390 }
1391 default -> throw new InternalError();
1392 }
1393 }
1394 if (firstObjIndex != -1 &&
1395 firstObjIndex + numObjFields != fields.length)
1396 {
1397 throw new InvalidClassException(name, "illegal field order");
1398 }
1399 }
1400
1401 /**
1402 * If given class is the same as the class associated with this class
1403 * descriptor, returns reference to this class descriptor. Otherwise,
1404 * returns variant of this class descriptor bound to given class.
1405 */
1406 private ObjectStreamClass getVariantFor(Class<?> cl)
1407 throws InvalidClassException
1408 {
1409 if (this.cl == cl) {
1410 return this;
1411 }
1412 ObjectStreamClass desc = new ObjectStreamClass();
1413 if (isProxy) {
1414 desc.initProxy(cl, null, superDesc);
1415 } else {
1416 desc.initNonProxy(this, cl, null, superDesc);
1417 }
1418 return desc;
1419 }
1420
1421 /**
1422 * Returns public no-arg constructor of given class, or null if none found.
1423 * Access checks are disabled on the returned constructor (if any), since
1424 * the defining class may still be non-public.
1425 */
1426 private static Constructor<?> getExternalizableConstructor(Class<?> cl) {
1427 try {
1428 Constructor<?> cons = cl.getDeclaredConstructor((Class<?>[]) null);
1429 cons.setAccessible(true);
1430 return ((cons.getModifiers() & Modifier.PUBLIC) != 0) ?
1431 cons : null;
1432 } catch (NoSuchMethodException ex) {
1433 return null;
1434 }
1435 }
1436
1437 /**
1438 * Returns subclass-accessible no-arg constructor of first non-serializable
1439 * superclass, or null if none found. Access checks are disabled on the
1440 * returned constructor (if any).
1441 */
1442 private static Constructor<?> getSerializableConstructor(Class<?> cl) {
1443 return reflFactory.newConstructorForSerialization(cl);
1444 }
1445
1446 /**
1447 * Returns the canonical constructor for the given record class, or null if
1448 * the not found ( which should never happen for correctly generated record
1449 * classes ).
1450 */
1451 @SuppressWarnings("removal")
1452 private static MethodHandle canonicalRecordCtr(Class<?> cls) {
1453 assert cls.isRecord() : "Expected record, got: " + cls;
1454 PrivilegedAction<MethodHandle> pa = () -> {
1455 Class<?>[] paramTypes = Arrays.stream(cls.getRecordComponents())
1456 .map(RecordComponent::getType)
1457 .toArray(Class<?>[]::new);
1458 try {
1459 Constructor<?> ctr = cls.getDeclaredConstructor(paramTypes);
1460 ctr.setAccessible(true);
1461 return MethodHandles.lookup().unreflectConstructor(ctr);
1462 } catch (IllegalAccessException | NoSuchMethodException e) {
1463 return null;
1464 }
1465 };
1466 return AccessController.doPrivileged(pa);
1467 }
1468
1469 /**
1470 * Returns the canonical constructor, if the local class equivalent of this
1471 * stream class descriptor is a record class, otherwise null.
1472 */
1473 MethodHandle getRecordConstructor() {
1474 return canonicalCtr;
1475 }
1476
1477 /**
1478 * Returns non-static, non-abstract method with given signature provided it
1479 * is defined by or accessible (via inheritance) by the given class, or
1480 * null if no match found. Access checks are disabled on the returned
1481 * method (if any).
1482 */
1483 private static Method getInheritableMethod(Class<?> cl, String name,
1484 Class<?>[] argTypes,
1485 Class<?> returnType)
1486 {
1487 Method meth = null;
1488 Class<?> defCl = cl;
1489 while (defCl != null) {
1490 try {
1491 meth = defCl.getDeclaredMethod(name, argTypes);
1492 break;
1493 } catch (NoSuchMethodException ex) {
1494 defCl = defCl.getSuperclass();
1495 }
1496 }
1497
1498 if ((meth == null) || (meth.getReturnType() != returnType)) {
1499 return null;
1500 }
1501 meth.setAccessible(true);
1502 int mods = meth.getModifiers();
1503 if ((mods & (Modifier.STATIC | Modifier.ABSTRACT)) != 0) {
1504 return null;
1505 } else if ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) != 0) {
1506 return meth;
1507 } else if ((mods & Modifier.PRIVATE) != 0) {
1508 return (cl == defCl) ? meth : null;
1509 } else {
1510 return packageEquals(cl, defCl) ? meth : null;
1511 }
1512 }
1513
1514 /**
1515 * Returns non-static private method with given signature defined by given
1516 * class, or null if none found. Access checks are disabled on the
1517 * returned method (if any).
1518 */
1519 private static Method getPrivateMethod(Class<?> cl, String name,
1520 Class<?>[] argTypes,
1521 Class<?> returnType)
1522 {
1523 try {
1524 Method meth = cl.getDeclaredMethod(name, argTypes);
1525 meth.setAccessible(true);
1526 int mods = meth.getModifiers();
1527 return ((meth.getReturnType() == returnType) &&
1528 ((mods & Modifier.STATIC) == 0) &&
1529 ((mods & Modifier.PRIVATE) != 0)) ? meth : null;
1530 } catch (NoSuchMethodException ex) {
1531 return null;
1532 }
1533 }
1534
1535 /**
1536 * Returns true if classes are defined in the same runtime package, false
1537 * otherwise.
1538 */
1539 private static boolean packageEquals(Class<?> cl1, Class<?> cl2) {
1540 return cl1.getClassLoader() == cl2.getClassLoader() &&
1541 cl1.getPackageName() == cl2.getPackageName();
1542 }
1543
1544 /**
1545 * Compares class names for equality, ignoring package names. Returns true
1546 * if class names equal, false otherwise.
1547 */
1548 private static boolean classNamesEqual(String name1, String name2) {
1549 int idx1 = name1.lastIndexOf('.') + 1;
1550 int idx2 = name2.lastIndexOf('.') + 1;
1551 int len1 = name1.length() - idx1;
1552 int len2 = name2.length() - idx2;
1553 return len1 == len2 &&
1554 name1.regionMatches(idx1, name2, idx2, len1);
1555 }
1556
1557 /**
1558 * Returns JVM type signature for given list of parameters and return type.
1559 */
1560 private static String getMethodSignature(Class<?>[] paramTypes,
1561 Class<?> retType)
1562 {
1563 StringBuilder sb = new StringBuilder();
1564 sb.append('(');
1565 for (int i = 0; i < paramTypes.length; i++) {
1566 sb.append(paramTypes[i].descriptorString());
1567 }
1568 sb.append(')');
1569 sb.append(retType.descriptorString());
1570 return sb.toString();
1571 }
1572
1573 /**
1574 * Convenience method for throwing an exception that is either a
1575 * RuntimeException, Error, or of some unexpected type (in which case it is
1576 * wrapped inside an IOException).
1577 */
1578 private static void throwMiscException(Throwable th) throws IOException {
1579 if (th instanceof RuntimeException) {
1580 throw (RuntimeException) th;
1581 } else if (th instanceof Error) {
1582 throw (Error) th;
1583 } else {
1584 throw new IOException("unexpected exception type", th);
1585 }
1586 }
1587
1588 /**
1589 * Returns ObjectStreamField array describing the serializable fields of
1590 * the given class. Serializable fields backed by an actual field of the
1591 * class are represented by ObjectStreamFields with corresponding non-null
1592 * Field objects. Throws InvalidClassException if the (explicitly
1593 * declared) serializable fields are invalid.
1594 */
1595 private static ObjectStreamField[] getSerialFields(Class<?> cl)
1596 throws InvalidClassException
1597 {
1598 if (!Serializable.class.isAssignableFrom(cl))
1599 return NO_FIELDS;
1600
1601 ObjectStreamField[] fields;
1602 if (cl.isRecord()) {
1603 fields = getDefaultSerialFields(cl);
1604 Arrays.sort(fields);
1605 } else if (!Externalizable.class.isAssignableFrom(cl) &&
1606 !Proxy.isProxyClass(cl) &&
1607 !cl.isInterface()) {
1608 if ((fields = getDeclaredSerialFields(cl)) == null) {
1609 fields = getDefaultSerialFields(cl);
1610 }
1611 Arrays.sort(fields);
1612 } else {
1613 fields = NO_FIELDS;
1614 }
1615 return fields;
1616 }
1617
1618 /**
1619 * Returns serializable fields of given class as defined explicitly by a
1620 * "serialPersistentFields" field, or null if no appropriate
1621 * "serialPersistentFields" field is defined. Serializable fields backed
1622 * by an actual field of the class are represented by ObjectStreamFields
1623 * with corresponding non-null Field objects. For compatibility with past
1624 * releases, a "serialPersistentFields" field with a null value is
1625 * considered equivalent to not declaring "serialPersistentFields". Throws
1626 * InvalidClassException if the declared serializable fields are
1627 * invalid--e.g., if multiple fields share the same name.
1628 */
1629 private static ObjectStreamField[] getDeclaredSerialFields(Class<?> cl)
1630 throws InvalidClassException
1631 {
1632 ObjectStreamField[] serialPersistentFields = null;
1633 try {
1634 Field f = cl.getDeclaredField("serialPersistentFields");
1635 int mask = Modifier.PRIVATE | Modifier.STATIC | Modifier.FINAL;
1636 if ((f.getModifiers() & mask) == mask) {
1637 f.setAccessible(true);
1638 serialPersistentFields = (ObjectStreamField[]) f.get(null);
1639 }
1640 } catch (Exception ex) {
1641 }
1642 if (serialPersistentFields == null) {
1643 return null;
1644 } else if (serialPersistentFields.length == 0) {
1645 return NO_FIELDS;
1646 }
1647
1648 ObjectStreamField[] boundFields =
1649 new ObjectStreamField[serialPersistentFields.length];
1650 Set<String> fieldNames = HashSet.newHashSet(serialPersistentFields.length);
1651
1652 for (int i = 0; i < serialPersistentFields.length; i++) {
1653 ObjectStreamField spf = serialPersistentFields[i];
1654
1655 String fname = spf.getName();
1656 if (fieldNames.contains(fname)) {
1657 throw new InvalidClassException(
1658 "multiple serializable fields named " + fname);
1659 }
1660 fieldNames.add(fname);
1661
1662 try {
1663 Field f = cl.getDeclaredField(fname);
1664 if ((f.getType() == spf.getType()) &&
1665 ((f.getModifiers() & Modifier.STATIC) == 0))
1666 {
1667 boundFields[i] =
1668 new ObjectStreamField(f, spf.isUnshared(), true);
1669 }
1670 } catch (NoSuchFieldException ex) {
1671 }
1672 if (boundFields[i] == null) {
1673 boundFields[i] = new ObjectStreamField(
1674 fname, spf.getType(), spf.isUnshared());
1675 }
1676 }
1677 return boundFields;
1678 }
1679
1680 /**
1681 * Returns array of ObjectStreamFields corresponding to all non-static
1682 * non-transient fields declared by given class. Each ObjectStreamField
1683 * contains a Field object for the field it represents. If no default
1684 * serializable fields exist, NO_FIELDS is returned.
1685 */
1686 private static ObjectStreamField[] getDefaultSerialFields(Class<?> cl) {
1687 Field[] clFields = cl.getDeclaredFields();
1688 ArrayList<ObjectStreamField> list = new ArrayList<>();
1689 int mask = Modifier.STATIC | Modifier.TRANSIENT;
1690
1691 for (int i = 0; i < clFields.length; i++) {
1692 if ((clFields[i].getModifiers() & mask) == 0) {
1693 list.add(new ObjectStreamField(clFields[i], false, true));
1694 }
1695 }
1696 int size = list.size();
1697 return (size == 0) ? NO_FIELDS :
1698 list.toArray(new ObjectStreamField[size]);
1699 }
1700
1701 /**
1702 * Returns explicit serial version UID value declared by given class, or
1703 * null if none.
1704 */
1705 private static Long getDeclaredSUID(Class<?> cl) {
1706 try {
1707 Field f = cl.getDeclaredField("serialVersionUID");
1708 int mask = Modifier.STATIC | Modifier.FINAL;
1709 if ((f.getModifiers() & mask) == mask) {
1710 f.setAccessible(true);
1711 return f.getLong(null);
1712 }
1713 } catch (Exception ex) {
1714 }
1715 return null;
1716 }
1717
1718 /**
1719 * Computes the default serial version UID value for the given class.
1720 */
1721 private static long computeDefaultSUID(Class<?> cl) {
1722 if (!Serializable.class.isAssignableFrom(cl) || Proxy.isProxyClass(cl))
1723 {
1724 return 0L;
1725 }
1726
1727 try {
1728 ByteArrayOutputStream bout = new ByteArrayOutputStream();
1729 DataOutputStream dout = new DataOutputStream(bout);
1730
1731 dout.writeUTF(cl.getName());
1732
1733 int classMods = cl.getModifiers() &
1734 (Modifier.PUBLIC | Modifier.FINAL |
1735 Modifier.INTERFACE | Modifier.ABSTRACT);
1736
1737 /*
1738 * compensate for javac bug in which ABSTRACT bit was set for an
1739 * interface only if the interface declared methods
1740 */
1741 Method[] methods = cl.getDeclaredMethods();
1742 if ((classMods & Modifier.INTERFACE) != 0) {
1743 classMods = (methods.length > 0) ?
1744 (classMods | Modifier.ABSTRACT) :
1745 (classMods & ~Modifier.ABSTRACT);
1746 }
1747 dout.writeInt(classMods);
1748
1749 if (!cl.isArray()) {
1750 /*
1751 * compensate for change in 1.2FCS in which
1752 * Class.getInterfaces() was modified to return Cloneable and
1753 * Serializable for array classes.
1754 */
1755 Class<?>[] interfaces = cl.getInterfaces();
1756 String[] ifaceNames = new String[interfaces.length];
1757 for (int i = 0; i < interfaces.length; i++) {
1758 ifaceNames[i] = interfaces[i].getName();
1759 }
1760 Arrays.sort(ifaceNames);
1761 for (int i = 0; i < ifaceNames.length; i++) {
1762 dout.writeUTF(ifaceNames[i]);
1763 }
1764 }
1765
1766 Field[] fields = cl.getDeclaredFields();
1767 MemberSignature[] fieldSigs = new MemberSignature[fields.length];
1768 for (int i = 0; i < fields.length; i++) {
1769 fieldSigs[i] = new MemberSignature(fields[i]);
1770 }
1771 Arrays.sort(fieldSigs, new Comparator<>() {
1772 public int compare(MemberSignature ms1, MemberSignature ms2) {
1773 return ms1.name.compareTo(ms2.name);
1774 }
1775 });
1776 for (int i = 0; i < fieldSigs.length; i++) {
1777 MemberSignature sig = fieldSigs[i];
1778 int mods = sig.member.getModifiers() &
1779 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1780 Modifier.STATIC | Modifier.FINAL | Modifier.VOLATILE |
1781 Modifier.TRANSIENT);
1782 if (((mods & Modifier.PRIVATE) == 0) ||
1783 ((mods & (Modifier.STATIC | Modifier.TRANSIENT)) == 0))
1784 {
1785 dout.writeUTF(sig.name);
1786 dout.writeInt(mods);
1787 dout.writeUTF(sig.signature);
1788 }
1789 }
1790
1791 if (hasStaticInitializer(cl)) {
1792 dout.writeUTF("<clinit>");
1793 dout.writeInt(Modifier.STATIC);
1794 dout.writeUTF("()V");
1795 }
1796
1797 Constructor<?>[] cons = cl.getDeclaredConstructors();
1798 MemberSignature[] consSigs = new MemberSignature[cons.length];
1799 for (int i = 0; i < cons.length; i++) {
1800 consSigs[i] = new MemberSignature(cons[i]);
1801 }
1802 Arrays.sort(consSigs, new Comparator<>() {
1803 public int compare(MemberSignature ms1, MemberSignature ms2) {
1804 return ms1.signature.compareTo(ms2.signature);
1805 }
1806 });
1807 for (int i = 0; i < consSigs.length; i++) {
1808 MemberSignature sig = consSigs[i];
1809 int mods = sig.member.getModifiers() &
1810 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1811 Modifier.STATIC | Modifier.FINAL |
1812 Modifier.SYNCHRONIZED | Modifier.NATIVE |
1813 Modifier.ABSTRACT | Modifier.STRICT);
1814 if ((mods & Modifier.PRIVATE) == 0) {
1815 dout.writeUTF("<init>");
1816 dout.writeInt(mods);
1817 dout.writeUTF(sig.signature.replace('/', '.'));
1818 }
1819 }
1820
1821 MemberSignature[] methSigs = new MemberSignature[methods.length];
1822 for (int i = 0; i < methods.length; i++) {
1823 methSigs[i] = new MemberSignature(methods[i]);
1824 }
1825 Arrays.sort(methSigs, new Comparator<>() {
1826 public int compare(MemberSignature ms1, MemberSignature ms2) {
1827 int comp = ms1.name.compareTo(ms2.name);
1828 if (comp == 0) {
1829 comp = ms1.signature.compareTo(ms2.signature);
1830 }
1831 return comp;
1832 }
1833 });
1834 for (int i = 0; i < methSigs.length; i++) {
1835 MemberSignature sig = methSigs[i];
1836 int mods = sig.member.getModifiers() &
1837 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED |
1838 Modifier.STATIC | Modifier.FINAL |
1839 Modifier.SYNCHRONIZED | Modifier.NATIVE |
1840 Modifier.ABSTRACT | Modifier.STRICT);
1841 if ((mods & Modifier.PRIVATE) == 0) {
1842 dout.writeUTF(sig.name);
1843 dout.writeInt(mods);
1844 dout.writeUTF(sig.signature.replace('/', '.'));
1845 }
1846 }
1847
1848 dout.flush();
1849
1850 MessageDigest md = MessageDigest.getInstance("SHA");
1851 byte[] hashBytes = md.digest(bout.toByteArray());
1852 long hash = 0;
1853 for (int i = Math.min(hashBytes.length, 8) - 1; i >= 0; i--) {
1854 hash = (hash << 8) | (hashBytes[i] & 0xFF);
1855 }
1856 return hash;
1857 } catch (IOException ex) {
1858 throw new InternalError(ex);
1859 } catch (NoSuchAlgorithmException ex) {
1860 throw new SecurityException(ex.getMessage());
1861 }
1862 }
1863
1864 /**
1865 * Returns true if the given class defines a static initializer method,
1866 * false otherwise.
1867 */
1868 private static native boolean hasStaticInitializer(Class<?> cl);
1869
1870 /**
1871 * Class for computing and caching field/constructor/method signatures
1872 * during serialVersionUID calculation.
1873 */
1874 private static class MemberSignature {
1875
1876 public final Member member;
1877 public final String name;
1878 public final String signature;
1879
1880 public MemberSignature(Field field) {
1881 member = field;
1882 name = field.getName();
1883 signature = field.getType().descriptorString();
1884 }
1885
1886 public MemberSignature(Constructor<?> cons) {
1887 member = cons;
1888 name = cons.getName();
1889 signature = getMethodSignature(
1890 cons.getParameterTypes(), Void.TYPE);
1891 }
1892
1893 public MemberSignature(Method meth) {
1894 member = meth;
1895 name = meth.getName();
1896 signature = getMethodSignature(
1897 meth.getParameterTypes(), meth.getReturnType());
1898 }
1899 }
1900
1901 /**
1902 * Class for setting and retrieving serializable field values in batch.
1903 */
1904 // REMIND: dynamically generate these?
1905 private static class FieldReflector {
1906
1907 /** handle for performing unsafe operations */
1908 private static final Unsafe unsafe = Unsafe.getUnsafe();
1909
1910 /** fields to operate on */
1911 private final ObjectStreamField[] fields;
1912 /** number of primitive fields */
1913 private final int numPrimFields;
1914 /** unsafe field keys for reading fields - may contain dupes */
1915 private final long[] readKeys;
1916 /** unsafe fields keys for writing fields - no dupes */
1917 private final long[] writeKeys;
1918 /** field data offsets */
1919 private final int[] offsets;
1920 /** field type codes */
1921 private final char[] typeCodes;
1922 /** field types */
1923 private final Class<?>[] types;
1924
1925 /**
1926 * Constructs FieldReflector capable of setting/getting values from the
1927 * subset of fields whose ObjectStreamFields contain non-null
1928 * reflective Field objects. ObjectStreamFields with null Fields are
1929 * treated as filler, for which get operations return default values
1930 * and set operations discard given values.
1931 */
1932 FieldReflector(ObjectStreamField[] fields) {
1933 this.fields = fields;
1934 int nfields = fields.length;
1935 readKeys = new long[nfields];
1936 writeKeys = new long[nfields];
1937 offsets = new int[nfields];
1938 typeCodes = new char[nfields];
1939 ArrayList<Class<?>> typeList = new ArrayList<>();
1940 Set<Long> usedKeys = new HashSet<>();
1941
1942
1943 for (int i = 0; i < nfields; i++) {
1944 ObjectStreamField f = fields[i];
1945 Field rf = f.getField();
1946 long key = (rf != null) ?
1947 unsafe.objectFieldOffset(rf) : Unsafe.INVALID_FIELD_OFFSET;
1948 readKeys[i] = key;
1949 writeKeys[i] = usedKeys.add(key) ?
1950 key : Unsafe.INVALID_FIELD_OFFSET;
1951 offsets[i] = f.getOffset();
1952 typeCodes[i] = f.getTypeCode();
1953 if (!f.isPrimitive()) {
1954 typeList.add((rf != null) ? rf.getType() : null);
1955 }
1956 }
1957
1958 types = typeList.toArray(new Class<?>[typeList.size()]);
1959 numPrimFields = nfields - types.length;
1960 }
1961
1962 /**
1963 * Returns list of ObjectStreamFields representing fields operated on
1964 * by this reflector. The shared/unshared values and Field objects
1965 * contained by ObjectStreamFields in the list reflect their bindings
1966 * to locally defined serializable fields.
1967 */
1968 ObjectStreamField[] getFields() {
1969 return fields;
1970 }
1971
1972 /**
1973 * Fetches the serializable primitive field values of object obj and
1974 * marshals them into byte array buf starting at offset 0. The caller
1975 * is responsible for ensuring that obj is of the proper type.
1976 */
1977 void getPrimFieldValues(Object obj, byte[] buf) {
1978 if (obj == null) {
1979 throw new NullPointerException();
1980 }
1981 /* assuming checkDefaultSerialize() has been called on the class
1982 * descriptor this FieldReflector was obtained from, no field keys
1983 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET.
1984 */
1985 for (int i = 0; i < numPrimFields; i++) {
1986 long key = readKeys[i];
1987 int off = offsets[i];
1988 switch (typeCodes[i]) {
1989 case 'Z' -> Bits.putBoolean(buf, off, unsafe.getBoolean(obj, key));
1990 case 'B' -> buf[off] = unsafe.getByte(obj, key);
1991 case 'C' -> Bits.putChar(buf, off, unsafe.getChar(obj, key));
1992 case 'S' -> Bits.putShort(buf, off, unsafe.getShort(obj, key));
1993 case 'I' -> Bits.putInt(buf, off, unsafe.getInt(obj, key));
1994 case 'F' -> Bits.putFloat(buf, off, unsafe.getFloat(obj, key));
1995 case 'J' -> Bits.putLong(buf, off, unsafe.getLong(obj, key));
1996 case 'D' -> Bits.putDouble(buf, off, unsafe.getDouble(obj, key));
1997 default -> throw new InternalError();
1998 }
1999 }
2000 }
2001
2002 /**
2003 * Sets the serializable primitive fields of object obj using values
2004 * unmarshalled from byte array buf starting at offset 0. The caller
2005 * is responsible for ensuring that obj is of the proper type.
2006 */
2007 void setPrimFieldValues(Object obj, byte[] buf) {
2008 if (obj == null) {
2009 throw new NullPointerException();
2010 }
2011 for (int i = 0; i < numPrimFields; i++) {
2012 long key = writeKeys[i];
2013 if (key == Unsafe.INVALID_FIELD_OFFSET) {
2014 continue; // discard value
2015 }
2016 int off = offsets[i];
2017 switch (typeCodes[i]) {
2018 case 'Z' -> unsafe.putBoolean(obj, key, Bits.getBoolean(buf, off));
2019 case 'B' -> unsafe.putByte(obj, key, buf[off]);
2020 case 'C' -> unsafe.putChar(obj, key, Bits.getChar(buf, off));
2021 case 'S' -> unsafe.putShort(obj, key, Bits.getShort(buf, off));
2022 case 'I' -> unsafe.putInt(obj, key, Bits.getInt(buf, off));
2023 case 'F' -> unsafe.putFloat(obj, key, Bits.getFloat(buf, off));
2024 case 'J' -> unsafe.putLong(obj, key, Bits.getLong(buf, off));
2025 case 'D' -> unsafe.putDouble(obj, key, Bits.getDouble(buf, off));
2026 default -> throw new InternalError();
2027 }
2028 }
2029 }
2030
2031 /**
2032 * Fetches the serializable object field values of object obj and
2033 * stores them in array vals starting at offset 0. The caller is
2034 * responsible for ensuring that obj is of the proper type.
2035 */
2036 void getObjFieldValues(Object obj, Object[] vals) {
2037 if (obj == null) {
2038 throw new NullPointerException();
2039 }
2040 /* assuming checkDefaultSerialize() has been called on the class
2041 * descriptor this FieldReflector was obtained from, no field keys
2042 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET.
2043 */
2044 for (int i = numPrimFields; i < fields.length; i++) {
2045 vals[offsets[i]] = switch (typeCodes[i]) {
2046 case 'L', '[' -> unsafe.getReference(obj, readKeys[i]);
2047 default -> throw new InternalError();
2048 };
2049 }
2050 }
2051
2052 /**
2053 * Checks that the given values, from array vals starting at offset 0,
2054 * are assignable to the given serializable object fields.
2055 * @throws ClassCastException if any value is not assignable
2056 */
2057 void checkObjectFieldValueTypes(Object obj, Object[] vals) {
2058 setObjFieldValues(obj, vals, true);
2059 }
2060
2061 /**
2062 * Sets the serializable object fields of object obj using values from
2063 * array vals starting at offset 0. The caller is responsible for
2064 * ensuring that obj is of the proper type; however, attempts to set a
2065 * field with a value of the wrong type will trigger an appropriate
2066 * ClassCastException.
2067 */
2068 void setObjFieldValues(Object obj, Object[] vals) {
2069 setObjFieldValues(obj, vals, false);
2070 }
2071
2072 private void setObjFieldValues(Object obj, Object[] vals, boolean dryRun) {
2073 if (obj == null) {
2074 throw new NullPointerException();
2075 }
2076 for (int i = numPrimFields; i < fields.length; i++) {
2077 long key = writeKeys[i];
2078 if (key == Unsafe.INVALID_FIELD_OFFSET) {
2079 continue; // discard value
2080 }
2081 switch (typeCodes[i]) {
2082 case 'L', '[' -> {
2083 Object val = vals[offsets[i]];
2084 if (val != null &&
2085 !types[i - numPrimFields].isInstance(val))
2086 {
2087 Field f = fields[i].getField();
2088 throw new ClassCastException(
2089 "cannot assign instance of " +
2090 val.getClass().getName() + " to field " +
2091 f.getDeclaringClass().getName() + "." +
2092 f.getName() + " of type " +
2093 f.getType().getName() + " in instance of " +
2094 obj.getClass().getName());
2095 }
2096 if (!dryRun)
2097 unsafe.putReference(obj, key, val);
2098 }
2099 default -> throw new InternalError();
2100 }
2101 }
2102 }
2103 }
2104
2105 /**
2106 * Matches given set of serializable fields with serializable fields
2107 * described by the given local class descriptor, and returns a
2108 * FieldReflector instance capable of setting/getting values from the
2109 * subset of fields that match (non-matching fields are treated as filler,
2110 * for which get operations return default values and set operations
2111 * discard given values). Throws InvalidClassException if unresolvable
2112 * type conflicts exist between the two sets of fields.
2113 */
2114 private static FieldReflector getReflector(ObjectStreamField[] fields,
2115 ObjectStreamClass localDesc)
2116 throws InvalidClassException
2117 {
2118 // class irrelevant if no fields
2119 Class<?> cl = (localDesc != null && fields.length > 0) ?
2120 localDesc.cl : Void.class;
2121
2122 var clReflectors = Caches.reflectors.get(cl);
2123 var key = new FieldReflectorKey(fields);
2124 var reflector = clReflectors.get(key);
2125 if (reflector == null) {
2126 reflector = new FieldReflector(matchFields(fields, localDesc));
2127 var oldReflector = clReflectors.putIfAbsent(key, reflector);
2128 if (oldReflector != null) {
2129 reflector = oldReflector;
2130 }
2131 }
2132 return reflector;
2133 }
2134
2135 /**
2136 * FieldReflector cache lookup key. Keys are considered equal if they
2137 * refer to equivalent field formats.
2138 */
2139 private static class FieldReflectorKey {
2140
2141 private final String[] sigs;
2142 private final int hash;
2143
2144 FieldReflectorKey(ObjectStreamField[] fields)
2145 {
2146 sigs = new String[2 * fields.length];
2147 for (int i = 0, j = 0; i < fields.length; i++) {
2148 ObjectStreamField f = fields[i];
2149 sigs[j++] = f.getName();
2150 sigs[j++] = f.getSignature();
2151 }
2152 hash = Arrays.hashCode(sigs);
2153 }
2154
2155 public int hashCode() {
2156 return hash;
2157 }
2158
2159 public boolean equals(Object obj) {
2160 return obj == this ||
2161 obj instanceof FieldReflectorKey other &&
2162 Arrays.equals(sigs, other.sigs);
2163 }
2164 }
2165
2166 /**
2167 * Matches given set of serializable fields with serializable fields
2168 * obtained from the given local class descriptor (which contain bindings
2169 * to reflective Field objects). Returns list of ObjectStreamFields in
2170 * which each ObjectStreamField whose signature matches that of a local
2171 * field contains a Field object for that field; unmatched
2172 * ObjectStreamFields contain null Field objects. Shared/unshared settings
2173 * of the returned ObjectStreamFields also reflect those of matched local
2174 * ObjectStreamFields. Throws InvalidClassException if unresolvable type
2175 * conflicts exist between the two sets of fields.
2176 */
2177 private static ObjectStreamField[] matchFields(ObjectStreamField[] fields,
2178 ObjectStreamClass localDesc)
2179 throws InvalidClassException
2180 {
2181 ObjectStreamField[] localFields = (localDesc != null) ?
2182 localDesc.fields : NO_FIELDS;
2183
2184 /*
2185 * Even if fields == localFields, we cannot simply return localFields
2186 * here. In previous implementations of serialization,
2187 * ObjectStreamField.getType() returned Object.class if the
2188 * ObjectStreamField represented a non-primitive field and belonged to
2189 * a non-local class descriptor. To preserve this (questionable)
2190 * behavior, the ObjectStreamField instances returned by matchFields
2191 * cannot report non-primitive types other than Object.class; hence
2192 * localFields cannot be returned directly.
2193 */
2194
2195 ObjectStreamField[] matches = new ObjectStreamField[fields.length];
2196 for (int i = 0; i < fields.length; i++) {
2197 ObjectStreamField f = fields[i], m = null;
2198 for (int j = 0; j < localFields.length; j++) {
2199 ObjectStreamField lf = localFields[j];
2200 if (f.getName().equals(lf.getName())) {
2201 if ((f.isPrimitive() || lf.isPrimitive()) &&
2202 f.getTypeCode() != lf.getTypeCode())
2203 {
2204 throw new InvalidClassException(localDesc.name,
2205 "incompatible types for field " + f.getName());
2206 }
2207 if (lf.getField() != null) {
2208 m = new ObjectStreamField(
2209 lf.getField(), lf.isUnshared(), false);
2210 } else {
2211 m = new ObjectStreamField(
2212 lf.getName(), lf.getSignature(), lf.isUnshared());
2213 }
2214 }
2215 }
2216 if (m == null) {
2217 m = new ObjectStreamField(
2218 f.getName(), f.getSignature(), false);
2219 }
2220 m.setOffset(f.getOffset());
2221 matches[i] = m;
2222 }
2223 return matches;
2224 }
2225
2226 /**
2227 * A LRA cache of record deserialization constructors.
2228 */
2229 @SuppressWarnings("serial")
2230 private static final class DeserializationConstructorsCache
2231 extends ConcurrentHashMap<DeserializationConstructorsCache.Key, MethodHandle> {
2232
2233 // keep max. 10 cached entries - when the 11th element is inserted the oldest
2234 // is removed and 10 remains - 11 is the biggest map size where internal
2235 // table of 16 elements is sufficient (inserting 12th element would resize it to 32)
2236 private static final int MAX_SIZE = 10;
2237 private Key.Impl first, last; // first and last in FIFO queue
2238
2239 DeserializationConstructorsCache() {
2240 // start small - if there is more than one shape of ObjectStreamClass
2241 // deserialized, there will typically be two (current version and previous version)
2242 super(2);
2243 }
2244
2245 MethodHandle get(ObjectStreamField[] fields) {
2246 return get(new Key.Lookup(fields));
2247 }
2248
2249 synchronized MethodHandle putIfAbsentAndGet(ObjectStreamField[] fields, MethodHandle mh) {
2250 Key.Impl key = new Key.Impl(fields);
2251 var oldMh = putIfAbsent(key, mh);
2252 if (oldMh != null) return oldMh;
2253 // else we did insert new entry -> link the new key as last
2254 if (last == null) {
2255 last = first = key;
2256 } else {
2257 last = (last.next = key);
2258 }
2259 // may need to remove first
2260 if (size() > MAX_SIZE) {
2261 assert first != null;
2262 remove(first);
2263 first = first.next;
2264 if (first == null) {
2265 last = null;
2266 }
2267 }
2268 return mh;
2269 }
2270
2271 // a key composed of ObjectStreamField[] names and types
2272 abstract static class Key {
2273 abstract int length();
2274 abstract String fieldName(int i);
2275 abstract Class<?> fieldType(int i);
2276
2277 @Override
2278 public final int hashCode() {
2279 int n = length();
2280 int h = 0;
2281 for (int i = 0; i < n; i++) h = h * 31 + fieldType(i).hashCode();
2282 for (int i = 0; i < n; i++) h = h * 31 + fieldName(i).hashCode();
2283 return h;
2284 }
2285
2286 @Override
2287 public final boolean equals(Object obj) {
2288 if (!(obj instanceof Key other)) return false;
2289 int n = length();
2290 if (n != other.length()) return false;
2291 for (int i = 0; i < n; i++) if (fieldType(i) != other.fieldType(i)) return false;
2292 for (int i = 0; i < n; i++) if (!fieldName(i).equals(other.fieldName(i))) return false;
2293 return true;
2294 }
2295
2296 // lookup key - just wraps ObjectStreamField[]
2297 static final class Lookup extends Key {
2298 final ObjectStreamField[] fields;
2299
2300 Lookup(ObjectStreamField[] fields) { this.fields = fields; }
2301
2302 @Override
2303 int length() { return fields.length; }
2304
2305 @Override
2306 String fieldName(int i) { return fields[i].getName(); }
2307
2308 @Override
2309 Class<?> fieldType(int i) { return fields[i].getType(); }
2310 }
2311
2312 // real key - copies field names and types and forms FIFO queue in cache
2313 static final class Impl extends Key {
2314 Impl next;
2315 final String[] fieldNames;
2316 final Class<?>[] fieldTypes;
2317
2318 Impl(ObjectStreamField[] fields) {
2319 this.fieldNames = new String[fields.length];
2320 this.fieldTypes = new Class<?>[fields.length];
2321 for (int i = 0; i < fields.length; i++) {
2322 fieldNames[i] = fields[i].getName();
2323 fieldTypes[i] = fields[i].getType();
2324 }
2325 }
2326
2327 @Override
2328 int length() { return fieldNames.length; }
2329
2330 @Override
2331 String fieldName(int i) { return fieldNames[i]; }
2332
2333 @Override
2334 Class<?> fieldType(int i) { return fieldTypes[i]; }
2335 }
2336 }
2337 }
2338
2339 /** Record specific support for retrieving and binding stream field values. */
2340 static final class RecordSupport {
2341 /**
2342 * Returns canonical record constructor adapted to take two arguments:
2343 * {@code (byte[] primValues, Object[] objValues)}
2344 * and return
2345 * {@code Object}
2346 */
2347 @SuppressWarnings("removal")
2348 static MethodHandle deserializationCtr(ObjectStreamClass desc) {
2349 // check the cached value 1st
2350 MethodHandle mh = desc.deserializationCtr;
2351 if (mh != null) return mh;
2352 mh = desc.deserializationCtrs.get(desc.getFields(false));
2353 if (mh != null) return desc.deserializationCtr = mh;
2354
2355 // retrieve record components
2356 RecordComponent[] recordComponents;
2357 try {
2358 Class<?> cls = desc.forClass();
2359 PrivilegedExceptionAction<RecordComponent[]> pa = cls::getRecordComponents;
2360 recordComponents = AccessController.doPrivileged(pa);
2361 } catch (PrivilegedActionException e) {
2362 throw new InternalError(e.getCause());
2363 }
2364
2365 // retrieve the canonical constructor
2366 // (T1, T2, ..., Tn):TR
2367 mh = desc.getRecordConstructor();
2368
2369 // change return type to Object
2370 // (T1, T2, ..., Tn):TR -> (T1, T2, ..., Tn):Object
2371 mh = mh.asType(mh.type().changeReturnType(Object.class));
2372
2373 // drop last 2 arguments representing primValues and objValues arrays
2374 // (T1, T2, ..., Tn):Object -> (T1, T2, ..., Tn, byte[], Object[]):Object
2375 mh = MethodHandles.dropArguments(mh, mh.type().parameterCount(), byte[].class, Object[].class);
2376
2377 for (int i = recordComponents.length-1; i >= 0; i--) {
2378 String name = recordComponents[i].getName();
2379 Class<?> type = recordComponents[i].getType();
2380 // obtain stream field extractor that extracts argument at
2381 // position i (Ti+1) from primValues and objValues arrays
2382 // (byte[], Object[]):Ti+1
2383 MethodHandle combiner = streamFieldExtractor(name, type, desc);
2384 // fold byte[] privValues and Object[] objValues into argument at position i (Ti+1)
2385 // (..., Ti, Ti+1, byte[], Object[]):Object -> (..., Ti, byte[], Object[]):Object
2386 mh = MethodHandles.foldArguments(mh, i, combiner);
2387 }
2388 // what we are left with is a MethodHandle taking just the primValues
2389 // and objValues arrays and returning the constructed record instance
2390 // (byte[], Object[]):Object
2391
2392 // store it into cache and return the 1st value stored
2393 return desc.deserializationCtr =
2394 desc.deserializationCtrs.putIfAbsentAndGet(desc.getFields(false), mh);
2395 }
2396
2397 /** Returns the number of primitive fields for the given descriptor. */
2398 private static int numberPrimValues(ObjectStreamClass desc) {
2399 ObjectStreamField[] fields = desc.getFields();
2400 int primValueCount = 0;
2401 for (int i = 0; i < fields.length; i++) {
2402 if (fields[i].isPrimitive())
2403 primValueCount++;
2404 else
2405 break; // can be no more
2406 }
2407 return primValueCount;
2408 }
2409
2410 /**
2411 * Returns extractor MethodHandle taking the primValues and objValues arrays
2412 * and extracting the argument of canonical constructor with given name and type
2413 * or producing default value for the given type if the field is absent.
2414 */
2415 private static MethodHandle streamFieldExtractor(String pName,
2416 Class<?> pType,
2417 ObjectStreamClass desc) {
2418 ObjectStreamField[] fields = desc.getFields(false);
2419
2420 for (int i = 0; i < fields.length; i++) {
2421 ObjectStreamField f = fields[i];
2422 String fName = f.getName();
2423 if (!fName.equals(pName))
2424 continue;
2425
2426 Class<?> fType = f.getField().getType();
2427 if (!pType.isAssignableFrom(fType))
2428 throw new InternalError(fName + " unassignable, pType:" + pType + ", fType:" + fType);
2429
2430 if (f.isPrimitive()) {
2431 // (byte[], int):fType
2432 MethodHandle mh = PRIM_VALUE_EXTRACTORS.get(fType);
2433 if (mh == null) {
2434 throw new InternalError("Unexpected type: " + fType);
2435 }
2436 // bind offset
2437 // (byte[], int):fType -> (byte[]):fType
2438 mh = MethodHandles.insertArguments(mh, 1, f.getOffset());
2439 // drop objValues argument
2440 // (byte[]):fType -> (byte[], Object[]):fType
2441 mh = MethodHandles.dropArguments(mh, 1, Object[].class);
2442 // adapt return type to pType
2443 // (byte[], Object[]):fType -> (byte[], Object[]):pType
2444 if (pType != fType) {
2445 mh = mh.asType(mh.type().changeReturnType(pType));
2446 }
2447 return mh;
2448 } else { // reference
2449 // (Object[], int):Object
2450 MethodHandle mh = MethodHandles.arrayElementGetter(Object[].class);
2451 // bind index
2452 // (Object[], int):Object -> (Object[]):Object
2453 mh = MethodHandles.insertArguments(mh, 1, i - numberPrimValues(desc));
2454 // drop primValues argument
2455 // (Object[]):Object -> (byte[], Object[]):Object
2456 mh = MethodHandles.dropArguments(mh, 0, byte[].class);
2457 // adapt return type to pType
2458 // (byte[], Object[]):Object -> (byte[], Object[]):pType
2459 if (pType != Object.class) {
2460 mh = mh.asType(mh.type().changeReturnType(pType));
2461 }
2462 return mh;
2463 }
2464 }
2465
2466 // return default value extractor if no field matches pName
2467 return MethodHandles.empty(MethodType.methodType(pType, byte[].class, Object[].class));
2468 }
2469
2470 private static final Map<Class<?>, MethodHandle> PRIM_VALUE_EXTRACTORS;
2471 static {
2472 var lkp = MethodHandles.lookup();
2473 try {
2474 PRIM_VALUE_EXTRACTORS = Map.of(
2475 byte.class, MethodHandles.arrayElementGetter(byte[].class),
2476 short.class, lkp.findStatic(Bits.class, "getShort", MethodType.methodType(short.class, byte[].class, int.class)),
2477 int.class, lkp.findStatic(Bits.class, "getInt", MethodType.methodType(int.class, byte[].class, int.class)),
2478 long.class, lkp.findStatic(Bits.class, "getLong", MethodType.methodType(long.class, byte[].class, int.class)),
2479 float.class, lkp.findStatic(Bits.class, "getFloat", MethodType.methodType(float.class, byte[].class, int.class)),
2480 double.class, lkp.findStatic(Bits.class, "getDouble", MethodType.methodType(double.class, byte[].class, int.class)),
2481 char.class, lkp.findStatic(Bits.class, "getChar", MethodType.methodType(char.class, byte[].class, int.class)),
2482 boolean.class, lkp.findStatic(Bits.class, "getBoolean", MethodType.methodType(boolean.class, byte[].class, int.class))
2483 );
2484 } catch (NoSuchMethodException | IllegalAccessException e) {
2485 throw new InternalError("Can't lookup Bits.getXXX", e);
2486 }
2487 }
2488 }
2489 }