1 /* 2 * Copyright (c) 1996, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package java.io; 27 28 import java.lang.ref.Reference; 29 import java.lang.ref.ReferenceQueue; 30 import java.lang.ref.SoftReference; 31 import java.lang.ref.WeakReference; 32 import java.lang.reflect.Constructor; 33 import java.lang.reflect.Field; 34 import java.lang.reflect.InvocationTargetException; 35 import java.lang.reflect.Member; 36 import java.lang.reflect.Method; 37 import java.lang.reflect.Modifier; 38 import java.lang.reflect.Proxy; 39 import java.security.AccessController; 40 import java.security.MessageDigest; 41 import java.security.NoSuchAlgorithmException; 42 import java.security.PrivilegedAction; 43 import java.util.ArrayList; 44 import java.util.Arrays; 45 import java.util.Collections; 46 import java.util.Comparator; 47 import java.util.HashSet; 48 import java.util.Set; 49 import java.util.concurrent.ConcurrentHashMap; 50 import java.util.concurrent.ConcurrentMap; 51 import jdk.internal.misc.Unsafe; 52 import jdk.internal.reflect.CallerSensitive; 53 import jdk.internal.reflect.Reflection; 54 import jdk.internal.reflect.ReflectionFactory; 55 import sun.reflect.misc.ReflectUtil; 56 57 import static java.io.ObjectStreamField.*; 58 59 /** 60 * Serialization's descriptor for classes. It contains the name and 61 * serialVersionUID of the class. The ObjectStreamClass for a specific class 62 * loaded in this Java VM can be found/created using the lookup method. 63 * 64 * <p>The algorithm to compute the SerialVersionUID is described in 65 * <a href="../../../platform/serialization/spec/class.html#4100">Object 66 * Serialization Specification, Section 4.6, Stream Unique Identifiers</a>. 67 * 68 * @author Mike Warres 69 * @author Roger Riggs 70 * @see ObjectStreamField 71 * @see <a href="../../../platform/serialization/spec/class.html">Object Serialization Specification, Section 4, Class Descriptors</a> 72 * @since 1.1 73 */ 74 public class ObjectStreamClass implements Serializable { 75 76 /** serialPersistentFields value indicating no serializable fields */ 77 public static final ObjectStreamField[] NO_FIELDS = 78 new ObjectStreamField[0]; 79 80 private static final long serialVersionUID = -6120832682080437368L; 81 private static final ObjectStreamField[] serialPersistentFields = 82 NO_FIELDS; 83 84 /** reflection factory for obtaining serialization constructors */ 85 private static final ReflectionFactory reflFactory = 86 AccessController.doPrivileged( 87 new ReflectionFactory.GetReflectionFactoryAction()); 88 89 private static class Caches { 90 /** cache mapping local classes -> descriptors */ 91 static final ConcurrentMap<WeakClassKey,Reference<?>> localDescs = 92 new ConcurrentHashMap<>(); 93 94 /** cache mapping field group/local desc pairs -> field reflectors */ 95 static final ConcurrentMap<FieldReflectorKey,Reference<?>> reflectors = 96 new ConcurrentHashMap<>(); 97 98 /** queue for WeakReferences to local classes */ 99 private static final ReferenceQueue<Class<?>> localDescsQueue = 100 new ReferenceQueue<>(); 101 /** queue for WeakReferences to field reflectors keys */ 102 private static final ReferenceQueue<Class<?>> reflectorsQueue = 103 new ReferenceQueue<>(); 104 } 105 106 /** class associated with this descriptor (if any) */ 107 private Class<?> cl; 108 /** name of class represented by this descriptor */ 109 private String name; 110 /** serialVersionUID of represented class (null if not computed yet) */ 111 private volatile Long suid; 112 113 /** true if represents dynamic proxy class */ 114 private boolean isProxy; 115 /** true if represents enum type */ 116 private boolean isEnum; 117 /** true if represented class implements Serializable */ 118 private boolean serializable; 119 /** true if represented class implements Externalizable */ 120 private boolean externalizable; 121 /** true if desc has data written by class-defined writeObject method */ 122 private boolean hasWriteObjectData; 123 /** 124 * true if desc has externalizable data written in block data format; this 125 * must be true by default to accommodate ObjectInputStream subclasses which 126 * override readClassDescriptor() to return class descriptors obtained from 127 * ObjectStreamClass.lookup() (see 4461737) 128 */ 129 private boolean hasBlockExternalData = true; 130 131 /** 132 * Contains information about InvalidClassException instances to be thrown 133 * when attempting operations on an invalid class. Note that instances of 134 * this class are immutable and are potentially shared among 135 * ObjectStreamClass instances. 136 */ 137 private static class ExceptionInfo { 138 private final String className; 139 private final String message; 140 141 ExceptionInfo(String cn, String msg) { 142 className = cn; 143 message = msg; 144 } 145 146 /** 147 * Returns (does not throw) an InvalidClassException instance created 148 * from the information in this object, suitable for being thrown by 149 * the caller. 150 */ 151 InvalidClassException newInvalidClassException() { 152 return new InvalidClassException(className, message); 153 } 154 } 155 156 /** exception (if any) thrown while attempting to resolve class */ 157 private ClassNotFoundException resolveEx; 158 /** exception (if any) to throw if non-enum deserialization attempted */ 159 private ExceptionInfo deserializeEx; 160 /** exception (if any) to throw if non-enum serialization attempted */ 161 private ExceptionInfo serializeEx; 162 /** exception (if any) to throw if default serialization attempted */ 163 private ExceptionInfo defaultSerializeEx; 164 165 /** serializable fields */ 166 private ObjectStreamField[] fields; 167 /** aggregate marshalled size of primitive fields */ 168 private int primDataSize; 169 /** number of non-primitive fields */ 170 private int numObjFields; 171 /** reflector for setting/getting serializable field values */ 172 private FieldReflector fieldRefl; 173 /** data layout of serialized objects described by this class desc */ 174 private volatile ClassDataSlot[] dataLayout; 175 176 /** serialization-appropriate constructor, or null if none */ 177 private Constructor<?> cons; 178 /** class-defined writeObject method, or null if none */ 179 private Method writeObjectMethod; 180 /** class-defined readObject method, or null if none */ 181 private Method readObjectMethod; 182 /** class-defined readObjectNoData method, or null if none */ 183 private Method readObjectNoDataMethod; 184 /** class-defined writeReplace method, or null if none */ 185 private Method writeReplaceMethod; 186 /** class-defined readResolve method, or null if none */ 187 private Method readResolveMethod; 188 189 /** local class descriptor for represented class (may point to self) */ 190 private ObjectStreamClass localDesc; 191 /** superclass descriptor appearing in stream */ 192 private ObjectStreamClass superDesc; 193 194 /** true if, and only if, the object has been correctly initialized */ 195 private boolean initialized; 196 197 /** 198 * Initializes native code. 199 */ 200 private static native void initNative(); 201 static { 202 initNative(); 203 } 204 205 /** 206 * Find the descriptor for a class that can be serialized. Creates an 207 * ObjectStreamClass instance if one does not exist yet for class. Null is 208 * returned if the specified class does not implement java.io.Serializable 209 * or java.io.Externalizable. 210 * 211 * @param cl class for which to get the descriptor 212 * @return the class descriptor for the specified class 213 */ 214 public static ObjectStreamClass lookup(Class<?> cl) { 215 return lookup(cl, false); 216 } 217 218 /** 219 * Returns the descriptor for any class, regardless of whether it 220 * implements {@link Serializable}. 221 * 222 * @param cl class for which to get the descriptor 223 * @return the class descriptor for the specified class 224 * @since 1.6 225 */ 226 public static ObjectStreamClass lookupAny(Class<?> cl) { 227 return lookup(cl, true); 228 } 229 230 /** 231 * Returns the name of the class described by this descriptor. 232 * This method returns the name of the class in the format that 233 * is used by the {@link Class#getName} method. 234 * 235 * @return a string representing the name of the class 236 */ 237 public String getName() { 238 return name; 239 } 240 241 /** 242 * Return the serialVersionUID for this class. The serialVersionUID 243 * defines a set of classes all with the same name that have evolved from a 244 * common root class and agree to be serialized and deserialized using a 245 * common format. NonSerializable classes have a serialVersionUID of 0L. 246 * 247 * @return the SUID of the class described by this descriptor 248 */ 249 public long getSerialVersionUID() { 250 // REMIND: synchronize instead of relying on volatile? 251 if (suid == null) { 252 suid = AccessController.doPrivileged( 253 new PrivilegedAction<Long>() { 254 public Long run() { 255 return computeDefaultSUID(cl); 256 } 257 } 258 ); 259 } 260 return suid.longValue(); 261 } 262 263 /** 264 * Return the class in the local VM that this version is mapped to. Null 265 * is returned if there is no corresponding local class. 266 * 267 * @return the <code>Class</code> instance that this descriptor represents 268 */ 269 @CallerSensitive 270 public Class<?> forClass() { 271 if (cl == null) { 272 return null; 273 } 274 requireInitialized(); 275 if (System.getSecurityManager() != null) { 276 Class<?> caller = Reflection.getCallerClass(); 277 if (ReflectUtil.needsPackageAccessCheck(caller.getClassLoader(), cl.getClassLoader())) { 278 ReflectUtil.checkPackageAccess(cl); 279 } 280 } 281 return cl; 282 } 283 284 /** 285 * Return an array of the fields of this serializable class. 286 * 287 * @return an array containing an element for each persistent field of 288 * this class. Returns an array of length zero if there are no 289 * fields. 290 * @since 1.2 291 */ 292 public ObjectStreamField[] getFields() { 293 return getFields(true); 294 } 295 296 /** 297 * Get the field of this class by name. 298 * 299 * @param name the name of the data field to look for 300 * @return The ObjectStreamField object of the named field or null if 301 * there is no such named field. 302 */ 303 public ObjectStreamField getField(String name) { 304 return getField(name, null); 305 } 306 307 /** 308 * Return a string describing this ObjectStreamClass. 309 */ 310 public String toString() { 311 return name + ": static final long serialVersionUID = " + 312 getSerialVersionUID() + "L;"; 313 } 314 315 /** 316 * Looks up and returns class descriptor for given class, or null if class 317 * is non-serializable and "all" is set to false. 318 * 319 * @param cl class to look up 320 * @param all if true, return descriptors for all classes; if false, only 321 * return descriptors for serializable classes 322 */ 323 static ObjectStreamClass lookup(Class<?> cl, boolean all) { 324 if (!(all || Serializable.class.isAssignableFrom(cl))) { 325 return null; 326 } 327 processQueue(Caches.localDescsQueue, Caches.localDescs); 328 WeakClassKey key = new WeakClassKey(cl, Caches.localDescsQueue); 329 Reference<?> ref = Caches.localDescs.get(key); 330 Object entry = null; 331 if (ref != null) { 332 entry = ref.get(); 333 } 334 EntryFuture future = null; 335 if (entry == null) { 336 EntryFuture newEntry = new EntryFuture(); 337 Reference<?> newRef = new SoftReference<>(newEntry); 338 do { 339 if (ref != null) { 340 Caches.localDescs.remove(key, ref); 341 } 342 ref = Caches.localDescs.putIfAbsent(key, newRef); 343 if (ref != null) { 344 entry = ref.get(); 345 } 346 } while (ref != null && entry == null); 347 if (entry == null) { 348 future = newEntry; 349 } 350 } 351 352 if (entry instanceof ObjectStreamClass) { // check common case first 353 return (ObjectStreamClass) entry; 354 } 355 if (entry instanceof EntryFuture) { 356 future = (EntryFuture) entry; 357 if (future.getOwner() == Thread.currentThread()) { 358 /* 359 * Handle nested call situation described by 4803747: waiting 360 * for future value to be set by a lookup() call further up the 361 * stack will result in deadlock, so calculate and set the 362 * future value here instead. 363 */ 364 entry = null; 365 } else { 366 entry = future.get(); 367 } 368 } 369 if (entry == null) { 370 try { 371 entry = new ObjectStreamClass(cl); 372 } catch (Throwable th) { 373 entry = th; 374 } 375 if (future.set(entry)) { 376 Caches.localDescs.put(key, new SoftReference<>(entry)); 377 } else { 378 // nested lookup call already set future 379 entry = future.get(); 380 } 381 } 382 383 if (entry instanceof ObjectStreamClass) { 384 return (ObjectStreamClass) entry; 385 } else if (entry instanceof RuntimeException) { 386 throw (RuntimeException) entry; 387 } else if (entry instanceof Error) { 388 throw (Error) entry; 389 } else { 390 throw new InternalError("unexpected entry: " + entry); 391 } 392 } 393 394 /** 395 * Placeholder used in class descriptor and field reflector lookup tables 396 * for an entry in the process of being initialized. (Internal) callers 397 * which receive an EntryFuture belonging to another thread as the result 398 * of a lookup should call the get() method of the EntryFuture; this will 399 * return the actual entry once it is ready for use and has been set(). To 400 * conserve objects, EntryFutures synchronize on themselves. 401 */ 402 private static class EntryFuture { 403 404 private static final Object unset = new Object(); 405 private final Thread owner = Thread.currentThread(); 406 private Object entry = unset; 407 408 /** 409 * Attempts to set the value contained by this EntryFuture. If the 410 * EntryFuture's value has not been set already, then the value is 411 * saved, any callers blocked in the get() method are notified, and 412 * true is returned. If the value has already been set, then no saving 413 * or notification occurs, and false is returned. 414 */ 415 synchronized boolean set(Object entry) { 416 if (this.entry != unset) { 417 return false; 418 } 419 this.entry = entry; 420 notifyAll(); 421 return true; 422 } 423 424 /** 425 * Returns the value contained by this EntryFuture, blocking if 426 * necessary until a value is set. 427 */ 428 synchronized Object get() { 429 boolean interrupted = false; 430 while (entry == unset) { 431 try { 432 wait(); 433 } catch (InterruptedException ex) { 434 interrupted = true; 435 } 436 } 437 if (interrupted) { 438 AccessController.doPrivileged( 439 new PrivilegedAction<>() { 440 public Void run() { 441 Thread.currentThread().interrupt(); 442 return null; 443 } 444 } 445 ); 446 } 447 return entry; 448 } 449 450 /** 451 * Returns the thread that created this EntryFuture. 452 */ 453 Thread getOwner() { 454 return owner; 455 } 456 } 457 458 /** 459 * Creates local class descriptor representing given class. 460 */ 461 private ObjectStreamClass(final Class<?> cl) { 462 this.cl = cl; 463 name = cl.getName(); 464 isProxy = Proxy.isProxyClass(cl); 465 isEnum = Enum.class.isAssignableFrom(cl); 466 serializable = Serializable.class.isAssignableFrom(cl); 467 externalizable = Externalizable.class.isAssignableFrom(cl); 468 469 Class<?> superCl = cl.getSuperclass(); 470 superDesc = (superCl != null) ? lookup(superCl, false) : null; 471 localDesc = this; 472 473 if (serializable) { 474 AccessController.doPrivileged(new PrivilegedAction<>() { 475 public Void run() { 476 if (isEnum) { 477 suid = Long.valueOf(0); 478 fields = NO_FIELDS; 479 return null; 480 } 481 if (cl.isArray()) { 482 fields = NO_FIELDS; 483 return null; 484 } 485 486 suid = getDeclaredSUID(cl); 487 try { 488 fields = getSerialFields(cl); 489 computeFieldOffsets(); 490 } catch (InvalidClassException e) { 491 serializeEx = deserializeEx = 492 new ExceptionInfo(e.classname, e.getMessage()); 493 fields = NO_FIELDS; 494 } 495 496 if (externalizable) { 497 cons = getExternalizableConstructor(cl); 498 } else { 499 cons = getSerializableConstructor(cl); 500 writeObjectMethod = getPrivateMethod(cl, "writeObject", 501 new Class<?>[] { ObjectOutputStream.class }, 502 Void.TYPE); 503 readObjectMethod = getPrivateMethod(cl, "readObject", 504 new Class<?>[] { ObjectInputStream.class }, 505 Void.TYPE); 506 readObjectNoDataMethod = getPrivateMethod( 507 cl, "readObjectNoData", null, Void.TYPE); 508 hasWriteObjectData = (writeObjectMethod != null); 509 } 510 writeReplaceMethod = getInheritableMethod( 511 cl, "writeReplace", null, Object.class); 512 readResolveMethod = getInheritableMethod( 513 cl, "readResolve", null, Object.class); 514 return null; 515 } 516 }); 517 } else { 518 suid = Long.valueOf(0); 519 fields = NO_FIELDS; 520 } 521 522 try { 523 fieldRefl = getReflector(fields, this); 524 } catch (InvalidClassException ex) { 525 // field mismatches impossible when matching local fields vs. self 526 throw new InternalError(ex); 527 } 528 529 if (deserializeEx == null) { 530 if (isEnum) { 531 deserializeEx = new ExceptionInfo(name, "enum type"); 532 } else if (cons == null) { 533 deserializeEx = new ExceptionInfo(name, "no valid constructor"); 534 } 535 } 536 for (int i = 0; i < fields.length; i++) { 537 if (fields[i].getField() == null) { 538 defaultSerializeEx = new ExceptionInfo( 539 name, "unmatched serializable field(s) declared"); 540 } 541 } 542 initialized = true; 543 } 544 545 /** 546 * Creates blank class descriptor which should be initialized via a 547 * subsequent call to initProxy(), initNonProxy() or readNonProxy(). 548 */ 549 ObjectStreamClass() { 550 } 551 552 /** 553 * Initializes class descriptor representing a proxy class. 554 */ 555 void initProxy(Class<?> cl, 556 ClassNotFoundException resolveEx, 557 ObjectStreamClass superDesc) 558 throws InvalidClassException 559 { 560 ObjectStreamClass osc = null; 561 if (cl != null) { 562 osc = lookup(cl, true); 563 if (!osc.isProxy) { 564 throw new InvalidClassException( 565 "cannot bind proxy descriptor to a non-proxy class"); 566 } 567 } 568 this.cl = cl; 569 this.resolveEx = resolveEx; 570 this.superDesc = superDesc; 571 isProxy = true; 572 serializable = true; 573 suid = Long.valueOf(0); 574 fields = NO_FIELDS; 575 if (osc != null) { 576 localDesc = osc; 577 name = localDesc.name; 578 externalizable = localDesc.externalizable; 579 writeReplaceMethod = localDesc.writeReplaceMethod; 580 readResolveMethod = localDesc.readResolveMethod; 581 deserializeEx = localDesc.deserializeEx; 582 cons = localDesc.cons; 583 } 584 fieldRefl = getReflector(fields, localDesc); 585 initialized = true; 586 } 587 588 /** 589 * Initializes class descriptor representing a non-proxy class. 590 */ 591 void initNonProxy(ObjectStreamClass model, 592 Class<?> cl, 593 ClassNotFoundException resolveEx, 594 ObjectStreamClass superDesc) 595 throws InvalidClassException 596 { 597 long suid = Long.valueOf(model.getSerialVersionUID()); 598 ObjectStreamClass osc = null; 599 if (cl != null) { 600 osc = lookup(cl, true); 601 if (osc.isProxy) { 602 throw new InvalidClassException( 603 "cannot bind non-proxy descriptor to a proxy class"); 604 } 605 if (model.isEnum != osc.isEnum) { 606 throw new InvalidClassException(model.isEnum ? 607 "cannot bind enum descriptor to a non-enum class" : 608 "cannot bind non-enum descriptor to an enum class"); 609 } 610 611 if (model.serializable == osc.serializable && 612 !cl.isArray() && 613 suid != osc.getSerialVersionUID()) { 614 throw new InvalidClassException(osc.name, 615 "local class incompatible: " + 616 "stream classdesc serialVersionUID = " + suid + 617 ", local class serialVersionUID = " + 618 osc.getSerialVersionUID()); 619 } 620 621 if (!classNamesEqual(model.name, osc.name)) { 622 throw new InvalidClassException(osc.name, 623 "local class name incompatible with stream class " + 624 "name \"" + model.name + "\""); 625 } 626 627 if (!model.isEnum) { 628 if ((model.serializable == osc.serializable) && 629 (model.externalizable != osc.externalizable)) { 630 throw new InvalidClassException(osc.name, 631 "Serializable incompatible with Externalizable"); 632 } 633 634 if ((model.serializable != osc.serializable) || 635 (model.externalizable != osc.externalizable) || 636 !(model.serializable || model.externalizable)) { 637 deserializeEx = new ExceptionInfo( 638 osc.name, "class invalid for deserialization"); 639 } 640 } 641 } 642 643 this.cl = cl; 644 this.resolveEx = resolveEx; 645 this.superDesc = superDesc; 646 name = model.name; 647 this.suid = suid; 648 isProxy = false; 649 isEnum = model.isEnum; 650 serializable = model.serializable; 651 externalizable = model.externalizable; 652 hasBlockExternalData = model.hasBlockExternalData; 653 hasWriteObjectData = model.hasWriteObjectData; 654 fields = model.fields; 655 primDataSize = model.primDataSize; 656 numObjFields = model.numObjFields; 657 658 if (osc != null) { 659 localDesc = osc; 660 writeObjectMethod = localDesc.writeObjectMethod; 661 readObjectMethod = localDesc.readObjectMethod; 662 readObjectNoDataMethod = localDesc.readObjectNoDataMethod; 663 writeReplaceMethod = localDesc.writeReplaceMethod; 664 readResolveMethod = localDesc.readResolveMethod; 665 if (deserializeEx == null) { 666 deserializeEx = localDesc.deserializeEx; 667 } 668 cons = localDesc.cons; 669 } 670 671 fieldRefl = getReflector(fields, localDesc); 672 // reassign to matched fields so as to reflect local unshared settings 673 fields = fieldRefl.getFields(); 674 initialized = true; 675 } 676 677 /** 678 * Reads non-proxy class descriptor information from given input stream. 679 * The resulting class descriptor is not fully functional; it can only be 680 * used as input to the ObjectInputStream.resolveClass() and 681 * ObjectStreamClass.initNonProxy() methods. 682 */ 683 void readNonProxy(ObjectInputStream in) 684 throws IOException, ClassNotFoundException 685 { 686 name = in.readUTF(); 687 suid = Long.valueOf(in.readLong()); 688 isProxy = false; 689 690 byte flags = in.readByte(); 691 hasWriteObjectData = 692 ((flags & ObjectStreamConstants.SC_WRITE_METHOD) != 0); 693 hasBlockExternalData = 694 ((flags & ObjectStreamConstants.SC_BLOCK_DATA) != 0); 695 externalizable = 696 ((flags & ObjectStreamConstants.SC_EXTERNALIZABLE) != 0); 697 boolean sflag = 698 ((flags & ObjectStreamConstants.SC_SERIALIZABLE) != 0); 699 if (externalizable && sflag) { 700 throw new InvalidClassException( 701 name, "serializable and externalizable flags conflict"); 702 } 703 serializable = externalizable || sflag; 704 isEnum = ((flags & ObjectStreamConstants.SC_ENUM) != 0); 705 if (isEnum && suid.longValue() != 0L) { 706 throw new InvalidClassException(name, 707 "enum descriptor has non-zero serialVersionUID: " + suid); 708 } 709 710 int numFields = in.readShort(); 711 if (isEnum && numFields != 0) { 712 throw new InvalidClassException(name, 713 "enum descriptor has non-zero field count: " + numFields); 714 } 715 fields = (numFields > 0) ? 716 new ObjectStreamField[numFields] : NO_FIELDS; 717 for (int i = 0; i < numFields; i++) { 718 char tcode = (char) in.readByte(); 719 String fname = in.readUTF(); 720 String signature = ((tcode == 'L') || (tcode == '[')) ? 721 in.readTypeString() : new String(new char[] { tcode }); 722 try { 723 fields[i] = new ObjectStreamField(fname, signature, false); 724 } catch (RuntimeException e) { 725 throw (IOException) new InvalidClassException(name, 726 "invalid descriptor for field " + fname).initCause(e); 727 } 728 } 729 computeFieldOffsets(); 730 } 731 732 /** 733 * Writes non-proxy class descriptor information to given output stream. 734 */ 735 void writeNonProxy(ObjectOutputStream out) throws IOException { 736 out.writeUTF(name); 737 out.writeLong(getSerialVersionUID()); 738 739 byte flags = 0; 740 if (externalizable) { 741 flags |= ObjectStreamConstants.SC_EXTERNALIZABLE; 742 int protocol = out.getProtocolVersion(); 743 if (protocol != ObjectStreamConstants.PROTOCOL_VERSION_1) { 744 flags |= ObjectStreamConstants.SC_BLOCK_DATA; 745 } 746 } else if (serializable) { 747 flags |= ObjectStreamConstants.SC_SERIALIZABLE; 748 } 749 if (hasWriteObjectData) { 750 flags |= ObjectStreamConstants.SC_WRITE_METHOD; 751 } 752 if (isEnum) { 753 flags |= ObjectStreamConstants.SC_ENUM; 754 } 755 out.writeByte(flags); 756 757 out.writeShort(fields.length); 758 for (int i = 0; i < fields.length; i++) { 759 ObjectStreamField f = fields[i]; 760 out.writeByte(f.getTypeCode()); 761 out.writeUTF(f.getName()); 762 if (!f.isPrimitive()) { 763 out.writeTypeString(f.getTypeString()); 764 } 765 } 766 } 767 768 /** 769 * Returns ClassNotFoundException (if any) thrown while attempting to 770 * resolve local class corresponding to this class descriptor. 771 */ 772 ClassNotFoundException getResolveException() { 773 return resolveEx; 774 } 775 776 /** 777 * Throws InternalError if not initialized. 778 */ 779 private final void requireInitialized() { 780 if (!initialized) 781 throw new InternalError("Unexpected call when not initialized"); 782 } 783 784 /** 785 * Throws an InvalidClassException if object instances referencing this 786 * class descriptor should not be allowed to deserialize. This method does 787 * not apply to deserialization of enum constants. 788 */ 789 void checkDeserialize() throws InvalidClassException { 790 requireInitialized(); 791 if (deserializeEx != null) { 792 throw deserializeEx.newInvalidClassException(); 793 } 794 } 795 796 /** 797 * Throws an InvalidClassException if objects whose class is represented by 798 * this descriptor should not be allowed to serialize. This method does 799 * not apply to serialization of enum constants. 800 */ 801 void checkSerialize() throws InvalidClassException { 802 requireInitialized(); 803 if (serializeEx != null) { 804 throw serializeEx.newInvalidClassException(); 805 } 806 } 807 808 /** 809 * Throws an InvalidClassException if objects whose class is represented by 810 * this descriptor should not be permitted to use default serialization 811 * (e.g., if the class declares serializable fields that do not correspond 812 * to actual fields, and hence must use the GetField API). This method 813 * does not apply to deserialization of enum constants. 814 */ 815 void checkDefaultSerialize() throws InvalidClassException { 816 requireInitialized(); 817 if (defaultSerializeEx != null) { 818 throw defaultSerializeEx.newInvalidClassException(); 819 } 820 } 821 822 /** 823 * Returns superclass descriptor. Note that on the receiving side, the 824 * superclass descriptor may be bound to a class that is not a superclass 825 * of the subclass descriptor's bound class. 826 */ 827 ObjectStreamClass getSuperDesc() { 828 requireInitialized(); 829 return superDesc; 830 } 831 832 /** 833 * Returns the "local" class descriptor for the class associated with this 834 * class descriptor (i.e., the result of 835 * ObjectStreamClass.lookup(this.forClass())) or null if there is no class 836 * associated with this descriptor. 837 */ 838 ObjectStreamClass getLocalDesc() { 839 requireInitialized(); 840 return localDesc; 841 } 842 843 /** 844 * Returns arrays of ObjectStreamFields representing the serializable 845 * fields of the represented class. If copy is true, a clone of this class 846 * descriptor's field array is returned, otherwise the array itself is 847 * returned. 848 */ 849 ObjectStreamField[] getFields(boolean copy) { 850 return copy ? fields.clone() : fields; 851 } 852 853 /** 854 * Looks up a serializable field of the represented class by name and type. 855 * A specified type of null matches all types, Object.class matches all 856 * non-primitive types, and any other non-null type matches assignable 857 * types only. Returns matching field, or null if no match found. 858 */ 859 ObjectStreamField getField(String name, Class<?> type) { 860 for (int i = 0; i < fields.length; i++) { 861 ObjectStreamField f = fields[i]; 862 if (f.getName().equals(name)) { 863 if (type == null || 864 (type == Object.class && !f.isPrimitive())) 865 { 866 return f; 867 } 868 Class<?> ftype = f.getType(); 869 if (ftype != null && type.isAssignableFrom(ftype)) { 870 return f; 871 } 872 } 873 } 874 return null; 875 } 876 877 /** 878 * Returns true if class descriptor represents a dynamic proxy class, false 879 * otherwise. 880 */ 881 boolean isProxy() { 882 requireInitialized(); 883 return isProxy; 884 } 885 886 /** 887 * Returns true if class descriptor represents an enum type, false 888 * otherwise. 889 */ 890 boolean isEnum() { 891 requireInitialized(); 892 return isEnum; 893 } 894 895 /** 896 * Returns true if represented class implements Externalizable, false 897 * otherwise. 898 */ 899 boolean isExternalizable() { 900 requireInitialized(); 901 return externalizable; 902 } 903 904 /** 905 * Returns true if represented class implements Serializable, false 906 * otherwise. 907 */ 908 boolean isSerializable() { 909 requireInitialized(); 910 return serializable; 911 } 912 913 /** 914 * Returns true if class descriptor represents externalizable class that 915 * has written its data in 1.2 (block data) format, false otherwise. 916 */ 917 boolean hasBlockExternalData() { 918 requireInitialized(); 919 return hasBlockExternalData; 920 } 921 922 /** 923 * Returns true if class descriptor represents serializable (but not 924 * externalizable) class which has written its data via a custom 925 * writeObject() method, false otherwise. 926 */ 927 boolean hasWriteObjectData() { 928 requireInitialized(); 929 return hasWriteObjectData; 930 } 931 932 /** 933 * Returns true if represented class is serializable/externalizable and can 934 * be instantiated by the serialization runtime--i.e., if it is 935 * externalizable and defines a public no-arg constructor, or if it is 936 * non-externalizable and its first non-serializable superclass defines an 937 * accessible no-arg constructor. Otherwise, returns false. 938 */ 939 boolean isInstantiable() { 940 requireInitialized(); 941 return (cons != null); 942 } 943 944 /** 945 * Returns true if represented class is serializable (but not 946 * externalizable) and defines a conformant writeObject method. Otherwise, 947 * returns false. 948 */ 949 boolean hasWriteObjectMethod() { 950 requireInitialized(); 951 return (writeObjectMethod != null); 952 } 953 954 /** 955 * Returns true if represented class is serializable (but not 956 * externalizable) and defines a conformant readObject method. Otherwise, 957 * returns false. 958 */ 959 boolean hasReadObjectMethod() { 960 requireInitialized(); 961 return (readObjectMethod != null); 962 } 963 964 /** 965 * Returns true if represented class is serializable (but not 966 * externalizable) and defines a conformant readObjectNoData method. 967 * Otherwise, returns false. 968 */ 969 boolean hasReadObjectNoDataMethod() { 970 requireInitialized(); 971 return (readObjectNoDataMethod != null); 972 } 973 974 /** 975 * Returns true if represented class is serializable or externalizable and 976 * defines a conformant writeReplace method. Otherwise, returns false. 977 */ 978 boolean hasWriteReplaceMethod() { 979 requireInitialized(); 980 return (writeReplaceMethod != null); 981 } 982 983 /** 984 * Returns true if represented class is serializable or externalizable and 985 * defines a conformant readResolve method. Otherwise, returns false. 986 */ 987 boolean hasReadResolveMethod() { 988 requireInitialized(); 989 return (readResolveMethod != null); 990 } 991 992 /** 993 * Creates a new instance of the represented class. If the class is 994 * externalizable, invokes its public no-arg constructor; otherwise, if the 995 * class is serializable, invokes the no-arg constructor of the first 996 * non-serializable superclass. Throws UnsupportedOperationException if 997 * this class descriptor is not associated with a class, if the associated 998 * class is non-serializable or if the appropriate no-arg constructor is 999 * inaccessible/unavailable. 1000 */ 1001 Object newInstance() 1002 throws InstantiationException, InvocationTargetException, 1003 UnsupportedOperationException 1004 { 1005 requireInitialized(); 1006 if (cons != null) { 1007 try { 1008 return cons.newInstance(); 1009 } catch (IllegalAccessException ex) { 1010 // should not occur, as access checks have been suppressed 1011 throw new InternalError(ex); 1012 } 1013 } else { 1014 throw new UnsupportedOperationException(); 1015 } 1016 } 1017 1018 /** 1019 * Invokes the writeObject method of the represented serializable class. 1020 * Throws UnsupportedOperationException if this class descriptor is not 1021 * associated with a class, or if the class is externalizable, 1022 * non-serializable or does not define writeObject. 1023 */ 1024 void invokeWriteObject(Object obj, ObjectOutputStream out) 1025 throws IOException, UnsupportedOperationException 1026 { 1027 requireInitialized(); 1028 if (writeObjectMethod != null) { 1029 try { 1030 writeObjectMethod.invoke(obj, new Object[]{ out }); 1031 } catch (InvocationTargetException ex) { 1032 Throwable th = ex.getTargetException(); 1033 if (th instanceof IOException) { 1034 throw (IOException) th; 1035 } else { 1036 throwMiscException(th); 1037 } 1038 } catch (IllegalAccessException ex) { 1039 // should not occur, as access checks have been suppressed 1040 throw new InternalError(ex); 1041 } 1042 } else { 1043 throw new UnsupportedOperationException(); 1044 } 1045 } 1046 1047 /** 1048 * Invokes the readObject method of the represented serializable class. 1049 * Throws UnsupportedOperationException if this class descriptor is not 1050 * associated with a class, or if the class is externalizable, 1051 * non-serializable or does not define readObject. 1052 */ 1053 void invokeReadObject(Object obj, ObjectInputStream in) 1054 throws ClassNotFoundException, IOException, 1055 UnsupportedOperationException 1056 { 1057 requireInitialized(); 1058 if (readObjectMethod != null) { 1059 try { 1060 readObjectMethod.invoke(obj, new Object[]{ in }); 1061 } catch (InvocationTargetException ex) { 1062 Throwable th = ex.getTargetException(); 1063 if (th instanceof ClassNotFoundException) { 1064 throw (ClassNotFoundException) th; 1065 } else if (th instanceof IOException) { 1066 throw (IOException) th; 1067 } else { 1068 throwMiscException(th); 1069 } 1070 } catch (IllegalAccessException ex) { 1071 // should not occur, as access checks have been suppressed 1072 throw new InternalError(ex); 1073 } 1074 } else { 1075 throw new UnsupportedOperationException(); 1076 } 1077 } 1078 1079 /** 1080 * Invokes the readObjectNoData method of the represented serializable 1081 * class. Throws UnsupportedOperationException if this class descriptor is 1082 * not associated with a class, or if the class is externalizable, 1083 * non-serializable or does not define readObjectNoData. 1084 */ 1085 void invokeReadObjectNoData(Object obj) 1086 throws IOException, UnsupportedOperationException 1087 { 1088 requireInitialized(); 1089 if (readObjectNoDataMethod != null) { 1090 try { 1091 readObjectNoDataMethod.invoke(obj, (Object[]) null); 1092 } catch (InvocationTargetException ex) { 1093 Throwable th = ex.getTargetException(); 1094 if (th instanceof ObjectStreamException) { 1095 throw (ObjectStreamException) th; 1096 } else { 1097 throwMiscException(th); 1098 } 1099 } catch (IllegalAccessException ex) { 1100 // should not occur, as access checks have been suppressed 1101 throw new InternalError(ex); 1102 } 1103 } else { 1104 throw new UnsupportedOperationException(); 1105 } 1106 } 1107 1108 /** 1109 * Invokes the writeReplace method of the represented serializable class and 1110 * returns the result. Throws UnsupportedOperationException if this class 1111 * descriptor is not associated with a class, or if the class is 1112 * non-serializable or does not define writeReplace. 1113 */ 1114 Object invokeWriteReplace(Object obj) 1115 throws IOException, UnsupportedOperationException 1116 { 1117 requireInitialized(); 1118 if (writeReplaceMethod != null) { 1119 try { 1120 return writeReplaceMethod.invoke(obj, (Object[]) null); 1121 } catch (InvocationTargetException ex) { 1122 Throwable th = ex.getTargetException(); 1123 if (th instanceof ObjectStreamException) { 1124 throw (ObjectStreamException) th; 1125 } else { 1126 throwMiscException(th); 1127 throw new InternalError(th); // never reached 1128 } 1129 } catch (IllegalAccessException ex) { 1130 // should not occur, as access checks have been suppressed 1131 throw new InternalError(ex); 1132 } 1133 } else { 1134 throw new UnsupportedOperationException(); 1135 } 1136 } 1137 1138 /** 1139 * Invokes the readResolve method of the represented serializable class and 1140 * returns the result. Throws UnsupportedOperationException if this class 1141 * descriptor is not associated with a class, or if the class is 1142 * non-serializable or does not define readResolve. 1143 */ 1144 Object invokeReadResolve(Object obj) 1145 throws IOException, UnsupportedOperationException 1146 { 1147 requireInitialized(); 1148 if (readResolveMethod != null) { 1149 try { 1150 return readResolveMethod.invoke(obj, (Object[]) null); 1151 } catch (InvocationTargetException ex) { 1152 Throwable th = ex.getTargetException(); 1153 if (th instanceof ObjectStreamException) { 1154 throw (ObjectStreamException) th; 1155 } else { 1156 throwMiscException(th); 1157 throw new InternalError(th); // never reached 1158 } 1159 } catch (IllegalAccessException ex) { 1160 // should not occur, as access checks have been suppressed 1161 throw new InternalError(ex); 1162 } 1163 } else { 1164 throw new UnsupportedOperationException(); 1165 } 1166 } 1167 1168 /** 1169 * Class representing the portion of an object's serialized form allotted 1170 * to data described by a given class descriptor. If "hasData" is false, 1171 * the object's serialized form does not contain data associated with the 1172 * class descriptor. 1173 */ 1174 static class ClassDataSlot { 1175 1176 /** class descriptor "occupying" this slot */ 1177 final ObjectStreamClass desc; 1178 /** true if serialized form includes data for this slot's descriptor */ 1179 final boolean hasData; 1180 1181 ClassDataSlot(ObjectStreamClass desc, boolean hasData) { 1182 this.desc = desc; 1183 this.hasData = hasData; 1184 } 1185 } 1186 1187 /** 1188 * Returns array of ClassDataSlot instances representing the data layout 1189 * (including superclass data) for serialized objects described by this 1190 * class descriptor. ClassDataSlots are ordered by inheritance with those 1191 * containing "higher" superclasses appearing first. The final 1192 * ClassDataSlot contains a reference to this descriptor. 1193 */ 1194 ClassDataSlot[] getClassDataLayout() throws InvalidClassException { 1195 // REMIND: synchronize instead of relying on volatile? 1196 if (dataLayout == null) { 1197 dataLayout = getClassDataLayout0(); 1198 } 1199 return dataLayout; 1200 } 1201 1202 private ClassDataSlot[] getClassDataLayout0() 1203 throws InvalidClassException 1204 { 1205 ArrayList<ClassDataSlot> slots = new ArrayList<>(); 1206 Class<?> start = cl, end = cl; 1207 1208 // locate closest non-serializable superclass 1209 while (end != null && Serializable.class.isAssignableFrom(end)) { 1210 end = end.getSuperclass(); 1211 } 1212 1213 HashSet<String> oscNames = new HashSet<>(3); 1214 1215 for (ObjectStreamClass d = this; d != null; d = d.superDesc) { 1216 if (oscNames.contains(d.name)) { 1217 throw new InvalidClassException("Circular reference."); 1218 } else { 1219 oscNames.add(d.name); 1220 } 1221 1222 // search up inheritance hierarchy for class with matching name 1223 String searchName = (d.cl != null) ? d.cl.getName() : d.name; 1224 Class<?> match = null; 1225 for (Class<?> c = start; c != end; c = c.getSuperclass()) { 1226 if (searchName.equals(c.getName())) { 1227 match = c; 1228 break; 1229 } 1230 } 1231 1232 // add "no data" slot for each unmatched class below match 1233 if (match != null) { 1234 for (Class<?> c = start; c != match; c = c.getSuperclass()) { 1235 slots.add(new ClassDataSlot( 1236 ObjectStreamClass.lookup(c, true), false)); 1237 } 1238 start = match.getSuperclass(); 1239 } 1240 1241 // record descriptor/class pairing 1242 slots.add(new ClassDataSlot(d.getVariantFor(match), true)); 1243 } 1244 1245 // add "no data" slot for any leftover unmatched classes 1246 for (Class<?> c = start; c != end; c = c.getSuperclass()) { 1247 slots.add(new ClassDataSlot( 1248 ObjectStreamClass.lookup(c, true), false)); 1249 } 1250 1251 // order slots from superclass -> subclass 1252 Collections.reverse(slots); 1253 return slots.toArray(new ClassDataSlot[slots.size()]); 1254 } 1255 1256 /** 1257 * Returns aggregate size (in bytes) of marshalled primitive field values 1258 * for represented class. 1259 */ 1260 int getPrimDataSize() { 1261 return primDataSize; 1262 } 1263 1264 /** 1265 * Returns number of non-primitive serializable fields of represented 1266 * class. 1267 */ 1268 int getNumObjFields() { 1269 return numObjFields; 1270 } 1271 1272 /** 1273 * Fetches the serializable primitive field values of object obj and 1274 * marshals them into byte array buf starting at offset 0. It is the 1275 * responsibility of the caller to ensure that obj is of the proper type if 1276 * non-null. 1277 */ 1278 void getPrimFieldValues(Object obj, byte[] buf) { 1279 fieldRefl.getPrimFieldValues(obj, buf); 1280 } 1281 1282 /** 1283 * Sets the serializable primitive fields of object obj using values 1284 * unmarshalled from byte array buf starting at offset 0. It is the 1285 * responsibility of the caller to ensure that obj is of the proper type if 1286 * non-null. 1287 */ 1288 void setPrimFieldValues(Object obj, byte[] buf) { 1289 fieldRefl.setPrimFieldValues(obj, buf); 1290 } 1291 1292 /** 1293 * Fetches the serializable object field values of object obj and stores 1294 * them in array vals starting at offset 0. It is the responsibility of 1295 * the caller to ensure that obj is of the proper type if non-null. 1296 */ 1297 void getObjFieldValues(Object obj, Object[] vals) { 1298 fieldRefl.getObjFieldValues(obj, vals); 1299 } 1300 1301 /** 1302 * Checks that the given values, from array vals starting at offset 0, 1303 * are assignable to the given serializable object fields. 1304 * @throws ClassCastException if any value is not assignable 1305 */ 1306 void checkObjFieldValueTypes(Object obj, Object[] vals) { 1307 fieldRefl.checkObjectFieldValueTypes(obj, vals); 1308 } 1309 1310 /** 1311 * Sets the serializable object fields of object obj using values from 1312 * array vals starting at offset 0. It is the responsibility of the caller 1313 * to ensure that obj is of the proper type if non-null. 1314 */ 1315 void setObjFieldValues(Object obj, Object[] vals) { 1316 fieldRefl.setObjFieldValues(obj, vals); 1317 } 1318 1319 /** 1320 * Calculates and sets serializable field offsets, as well as primitive 1321 * data size and object field count totals. Throws InvalidClassException 1322 * if fields are illegally ordered. 1323 */ 1324 private void computeFieldOffsets() throws InvalidClassException { 1325 primDataSize = 0; 1326 numObjFields = 0; 1327 int firstObjIndex = -1; 1328 1329 for (int i = 0; i < fields.length; i++) { 1330 ObjectStreamField f = fields[i]; 1331 switch (f.getTypeCode()) { 1332 case 'Z': 1333 case 'B': 1334 f.setOffset(primDataSize++); 1335 break; 1336 1337 case 'C': 1338 case 'S': 1339 f.setOffset(primDataSize); 1340 primDataSize += 2; 1341 break; 1342 1343 case 'I': 1344 case 'F': 1345 f.setOffset(primDataSize); 1346 primDataSize += 4; 1347 break; 1348 1349 case 'J': 1350 case 'D': 1351 f.setOffset(primDataSize); 1352 primDataSize += 8; 1353 break; 1354 1355 case '[': 1356 case 'L': 1357 f.setOffset(numObjFields++); 1358 if (firstObjIndex == -1) { 1359 firstObjIndex = i; 1360 } 1361 break; 1362 1363 default: 1364 throw new InternalError(); 1365 } 1366 } 1367 if (firstObjIndex != -1 && 1368 firstObjIndex + numObjFields != fields.length) 1369 { 1370 throw new InvalidClassException(name, "illegal field order"); 1371 } 1372 } 1373 1374 /** 1375 * If given class is the same as the class associated with this class 1376 * descriptor, returns reference to this class descriptor. Otherwise, 1377 * returns variant of this class descriptor bound to given class. 1378 */ 1379 private ObjectStreamClass getVariantFor(Class<?> cl) 1380 throws InvalidClassException 1381 { 1382 if (this.cl == cl) { 1383 return this; 1384 } 1385 ObjectStreamClass desc = new ObjectStreamClass(); 1386 if (isProxy) { 1387 desc.initProxy(cl, null, superDesc); 1388 } else { 1389 desc.initNonProxy(this, cl, null, superDesc); 1390 } 1391 return desc; 1392 } 1393 1394 /** 1395 * Returns public no-arg constructor of given class, or null if none found. 1396 * Access checks are disabled on the returned constructor (if any), since 1397 * the defining class may still be non-public. 1398 */ 1399 private static Constructor<?> getExternalizableConstructor(Class<?> cl) { 1400 try { 1401 Constructor<?> cons = cl.getDeclaredConstructor((Class<?>[]) null); 1402 cons.setAccessible(true); 1403 return ((cons.getModifiers() & Modifier.PUBLIC) != 0) ? 1404 cons : null; 1405 } catch (NoSuchMethodException ex) { 1406 return null; 1407 } 1408 } 1409 1410 /** 1411 * Returns subclass-accessible no-arg constructor of first non-serializable 1412 * superclass, or null if none found. Access checks are disabled on the 1413 * returned constructor (if any). 1414 */ 1415 private static Constructor<?> getSerializableConstructor(Class<?> cl) { 1416 Class<?> initCl = cl; 1417 while (Serializable.class.isAssignableFrom(initCl)) { 1418 if ((initCl = initCl.getSuperclass()) == null) { 1419 return null; 1420 } 1421 } 1422 try { 1423 Constructor<?> cons = initCl.getDeclaredConstructor((Class<?>[]) null); 1424 int mods = cons.getModifiers(); 1425 if ((mods & Modifier.PRIVATE) != 0 || 1426 ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) == 0 && 1427 !packageEquals(cl, initCl))) 1428 { 1429 return null; 1430 } 1431 cons = reflFactory.newConstructorForSerialization(cl, cons); 1432 cons.setAccessible(true); 1433 return cons; 1434 } catch (NoSuchMethodException ex) { 1435 return null; 1436 } 1437 } 1438 1439 /** 1440 * Returns non-static, non-abstract method with given signature provided it 1441 * is defined by or accessible (via inheritance) by the given class, or 1442 * null if no match found. Access checks are disabled on the returned 1443 * method (if any). 1444 */ 1445 private static Method getInheritableMethod(Class<?> cl, String name, 1446 Class<?>[] argTypes, 1447 Class<?> returnType) 1448 { 1449 Method meth = null; 1450 Class<?> defCl = cl; 1451 while (defCl != null) { 1452 try { 1453 meth = defCl.getDeclaredMethod(name, argTypes); 1454 break; 1455 } catch (NoSuchMethodException ex) { 1456 defCl = defCl.getSuperclass(); 1457 } 1458 } 1459 1460 if ((meth == null) || (meth.getReturnType() != returnType)) { 1461 return null; 1462 } 1463 meth.setAccessible(true); 1464 int mods = meth.getModifiers(); 1465 if ((mods & (Modifier.STATIC | Modifier.ABSTRACT)) != 0) { 1466 return null; 1467 } else if ((mods & (Modifier.PUBLIC | Modifier.PROTECTED)) != 0) { 1468 return meth; 1469 } else if ((mods & Modifier.PRIVATE) != 0) { 1470 return (cl == defCl) ? meth : null; 1471 } else { 1472 return packageEquals(cl, defCl) ? meth : null; 1473 } 1474 } 1475 1476 /** 1477 * Returns non-static private method with given signature defined by given 1478 * class, or null if none found. Access checks are disabled on the 1479 * returned method (if any). 1480 */ 1481 private static Method getPrivateMethod(Class<?> cl, String name, 1482 Class<?>[] argTypes, 1483 Class<?> returnType) 1484 { 1485 try { 1486 Method meth = cl.getDeclaredMethod(name, argTypes); 1487 meth.setAccessible(true); 1488 int mods = meth.getModifiers(); 1489 return ((meth.getReturnType() == returnType) && 1490 ((mods & Modifier.STATIC) == 0) && 1491 ((mods & Modifier.PRIVATE) != 0)) ? meth : null; 1492 } catch (NoSuchMethodException ex) { 1493 return null; 1494 } 1495 } 1496 1497 /** 1498 * Returns true if classes are defined in the same runtime package, false 1499 * otherwise. 1500 */ 1501 private static boolean packageEquals(Class<?> cl1, Class<?> cl2) { 1502 return (cl1.getClassLoader() == cl2.getClassLoader() && 1503 getPackageName(cl1).equals(getPackageName(cl2))); 1504 } 1505 1506 /** 1507 * Returns package name of given class. 1508 */ 1509 private static String getPackageName(Class<?> cl) { 1510 String s = cl.getName(); 1511 int i = s.lastIndexOf('['); 1512 i = (i < 0) ? 0 : i + 2; 1513 int j = s.lastIndexOf('.'); 1514 return (i < j) ? s.substring(i, j) : ""; 1515 } 1516 1517 /** 1518 * Compares class names for equality, ignoring package names. Returns true 1519 * if class names equal, false otherwise. 1520 */ 1521 private static boolean classNamesEqual(String name1, String name2) { 1522 int idx1 = name1.lastIndexOf('.') + 1; 1523 int idx2 = name2.lastIndexOf('.') + 1; 1524 int len1 = name1.length() - idx1; 1525 int len2 = name2.length() - idx2; 1526 return len1 == len2 && 1527 name1.regionMatches(idx1, name2, idx2, len1); 1528 } 1529 1530 /** 1531 * Returns JVM type signature for given list of parameters and return type. 1532 */ 1533 private static String getMethodSignature(Class<?>[] paramTypes, 1534 Class<?> retType) 1535 { 1536 StringBuilder sb = new StringBuilder(); 1537 sb.append('('); 1538 for (int i = 0; i < paramTypes.length; i++) { 1539 appendClassSignature(sb, paramTypes[i]); 1540 } 1541 sb.append(')'); 1542 appendClassSignature(sb, retType); 1543 return sb.toString(); 1544 } 1545 1546 /** 1547 * Convenience method for throwing an exception that is either a 1548 * RuntimeException, Error, or of some unexpected type (in which case it is 1549 * wrapped inside an IOException). 1550 */ 1551 private static void throwMiscException(Throwable th) throws IOException { 1552 if (th instanceof RuntimeException) { 1553 throw (RuntimeException) th; 1554 } else if (th instanceof Error) { 1555 throw (Error) th; 1556 } else { 1557 IOException ex = new IOException("unexpected exception type"); 1558 ex.initCause(th); 1559 throw ex; 1560 } 1561 } 1562 1563 /** 1564 * Returns ObjectStreamField array describing the serializable fields of 1565 * the given class. Serializable fields backed by an actual field of the 1566 * class are represented by ObjectStreamFields with corresponding non-null 1567 * Field objects. Throws InvalidClassException if the (explicitly 1568 * declared) serializable fields are invalid. 1569 */ 1570 private static ObjectStreamField[] getSerialFields(Class<?> cl) 1571 throws InvalidClassException 1572 { 1573 ObjectStreamField[] fields; 1574 if (Serializable.class.isAssignableFrom(cl) && 1575 !Externalizable.class.isAssignableFrom(cl) && 1576 !Proxy.isProxyClass(cl) && 1577 !cl.isInterface()) 1578 { 1579 if ((fields = getDeclaredSerialFields(cl)) == null) { 1580 fields = getDefaultSerialFields(cl); 1581 } 1582 Arrays.sort(fields); 1583 } else { 1584 fields = NO_FIELDS; 1585 } 1586 return fields; 1587 } 1588 1589 /** 1590 * Returns serializable fields of given class as defined explicitly by a 1591 * "serialPersistentFields" field, or null if no appropriate 1592 * "serialPersistentFields" field is defined. Serializable fields backed 1593 * by an actual field of the class are represented by ObjectStreamFields 1594 * with corresponding non-null Field objects. For compatibility with past 1595 * releases, a "serialPersistentFields" field with a null value is 1596 * considered equivalent to not declaring "serialPersistentFields". Throws 1597 * InvalidClassException if the declared serializable fields are 1598 * invalid--e.g., if multiple fields share the same name. 1599 */ 1600 private static ObjectStreamField[] getDeclaredSerialFields(Class<?> cl) 1601 throws InvalidClassException 1602 { 1603 ObjectStreamField[] serialPersistentFields = null; 1604 try { 1605 Field f = cl.getDeclaredField("serialPersistentFields"); 1606 int mask = Modifier.PRIVATE | Modifier.STATIC | Modifier.FINAL; 1607 if ((f.getModifiers() & mask) == mask) { 1608 f.setAccessible(true); 1609 serialPersistentFields = (ObjectStreamField[]) f.get(null); 1610 } 1611 } catch (Exception ex) { 1612 } 1613 if (serialPersistentFields == null) { 1614 return null; 1615 } else if (serialPersistentFields.length == 0) { 1616 return NO_FIELDS; 1617 } 1618 1619 ObjectStreamField[] boundFields = 1620 new ObjectStreamField[serialPersistentFields.length]; 1621 Set<String> fieldNames = new HashSet<>(serialPersistentFields.length); 1622 1623 for (int i = 0; i < serialPersistentFields.length; i++) { 1624 ObjectStreamField spf = serialPersistentFields[i]; 1625 1626 String fname = spf.getName(); 1627 if (fieldNames.contains(fname)) { 1628 throw new InvalidClassException( 1629 "multiple serializable fields named " + fname); 1630 } 1631 fieldNames.add(fname); 1632 1633 try { 1634 Field f = cl.getDeclaredField(fname); 1635 if ((f.getType() == spf.getType()) && 1636 ((f.getModifiers() & Modifier.STATIC) == 0)) 1637 { 1638 boundFields[i] = 1639 new ObjectStreamField(f, spf.isUnshared(), true); 1640 } 1641 } catch (NoSuchFieldException ex) { 1642 } 1643 if (boundFields[i] == null) { 1644 boundFields[i] = new ObjectStreamField( 1645 fname, spf.getType(), spf.isUnshared()); 1646 } 1647 } 1648 return boundFields; 1649 } 1650 1651 /** 1652 * Returns array of ObjectStreamFields corresponding to all non-static 1653 * non-transient fields declared by given class. Each ObjectStreamField 1654 * contains a Field object for the field it represents. If no default 1655 * serializable fields exist, NO_FIELDS is returned. 1656 */ 1657 private static ObjectStreamField[] getDefaultSerialFields(Class<?> cl) { 1658 Field[] clFields = cl.getDeclaredFields(); 1659 ArrayList<ObjectStreamField> list = new ArrayList<>(); 1660 int mask = Modifier.STATIC | Modifier.TRANSIENT; 1661 1662 for (int i = 0; i < clFields.length; i++) { 1663 if ((clFields[i].getModifiers() & mask) == 0) { 1664 list.add(new ObjectStreamField(clFields[i], false, true)); 1665 } 1666 } 1667 int size = list.size(); 1668 return (size == 0) ? NO_FIELDS : 1669 list.toArray(new ObjectStreamField[size]); 1670 } 1671 1672 /** 1673 * Returns explicit serial version UID value declared by given class, or 1674 * null if none. 1675 */ 1676 private static Long getDeclaredSUID(Class<?> cl) { 1677 try { 1678 Field f = cl.getDeclaredField("serialVersionUID"); 1679 int mask = Modifier.STATIC | Modifier.FINAL; 1680 if ((f.getModifiers() & mask) == mask) { 1681 f.setAccessible(true); 1682 return Long.valueOf(f.getLong(null)); 1683 } 1684 } catch (Exception ex) { 1685 } 1686 return null; 1687 } 1688 1689 /** 1690 * Computes the default serial version UID value for the given class. 1691 */ 1692 private static long computeDefaultSUID(Class<?> cl) { 1693 if (!Serializable.class.isAssignableFrom(cl) || Proxy.isProxyClass(cl)) 1694 { 1695 return 0L; 1696 } 1697 1698 try { 1699 ByteArrayOutputStream bout = new ByteArrayOutputStream(); 1700 DataOutputStream dout = new DataOutputStream(bout); 1701 1702 dout.writeUTF(cl.getName()); 1703 1704 int classMods = cl.getModifiers() & 1705 (Modifier.PUBLIC | Modifier.FINAL | 1706 Modifier.INTERFACE | Modifier.ABSTRACT); 1707 1708 /* 1709 * compensate for javac bug in which ABSTRACT bit was set for an 1710 * interface only if the interface declared methods 1711 */ 1712 Method[] methods = cl.getDeclaredMethods(); 1713 if ((classMods & Modifier.INTERFACE) != 0) { 1714 classMods = (methods.length > 0) ? 1715 (classMods | Modifier.ABSTRACT) : 1716 (classMods & ~Modifier.ABSTRACT); 1717 } 1718 dout.writeInt(classMods); 1719 1720 if (!cl.isArray()) { 1721 /* 1722 * compensate for change in 1.2FCS in which 1723 * Class.getInterfaces() was modified to return Cloneable and 1724 * Serializable for array classes. 1725 */ 1726 Class<?>[] interfaces = cl.getInterfaces(); 1727 String[] ifaceNames = new String[interfaces.length]; 1728 for (int i = 0; i < interfaces.length; i++) { 1729 ifaceNames[i] = interfaces[i].getName(); 1730 } 1731 Arrays.sort(ifaceNames); 1732 for (int i = 0; i < ifaceNames.length; i++) { 1733 dout.writeUTF(ifaceNames[i]); 1734 } 1735 } 1736 1737 Field[] fields = cl.getDeclaredFields(); 1738 MemberSignature[] fieldSigs = new MemberSignature[fields.length]; 1739 for (int i = 0; i < fields.length; i++) { 1740 fieldSigs[i] = new MemberSignature(fields[i]); 1741 } 1742 Arrays.sort(fieldSigs, new Comparator<>() { 1743 public int compare(MemberSignature ms1, MemberSignature ms2) { 1744 return ms1.name.compareTo(ms2.name); 1745 } 1746 }); 1747 for (int i = 0; i < fieldSigs.length; i++) { 1748 MemberSignature sig = fieldSigs[i]; 1749 int mods = sig.member.getModifiers() & 1750 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED | 1751 Modifier.STATIC | Modifier.FINAL | Modifier.VOLATILE | 1752 Modifier.TRANSIENT); 1753 if (((mods & Modifier.PRIVATE) == 0) || 1754 ((mods & (Modifier.STATIC | Modifier.TRANSIENT)) == 0)) 1755 { 1756 dout.writeUTF(sig.name); 1757 dout.writeInt(mods); 1758 dout.writeUTF(sig.signature); 1759 } 1760 } 1761 1762 if (hasStaticInitializer(cl)) { 1763 dout.writeUTF("<clinit>"); 1764 dout.writeInt(Modifier.STATIC); 1765 dout.writeUTF("()V"); 1766 } 1767 1768 Constructor<?>[] cons = cl.getDeclaredConstructors(); 1769 MemberSignature[] consSigs = new MemberSignature[cons.length]; 1770 for (int i = 0; i < cons.length; i++) { 1771 consSigs[i] = new MemberSignature(cons[i]); 1772 } 1773 Arrays.sort(consSigs, new Comparator<>() { 1774 public int compare(MemberSignature ms1, MemberSignature ms2) { 1775 return ms1.signature.compareTo(ms2.signature); 1776 } 1777 }); 1778 for (int i = 0; i < consSigs.length; i++) { 1779 MemberSignature sig = consSigs[i]; 1780 int mods = sig.member.getModifiers() & 1781 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED | 1782 Modifier.STATIC | Modifier.FINAL | 1783 Modifier.SYNCHRONIZED | Modifier.NATIVE | 1784 Modifier.ABSTRACT | Modifier.STRICT); 1785 if ((mods & Modifier.PRIVATE) == 0) { 1786 dout.writeUTF("<init>"); 1787 dout.writeInt(mods); 1788 dout.writeUTF(sig.signature.replace('/', '.')); 1789 } 1790 } 1791 1792 MemberSignature[] methSigs = new MemberSignature[methods.length]; 1793 for (int i = 0; i < methods.length; i++) { 1794 methSigs[i] = new MemberSignature(methods[i]); 1795 } 1796 Arrays.sort(methSigs, new Comparator<>() { 1797 public int compare(MemberSignature ms1, MemberSignature ms2) { 1798 int comp = ms1.name.compareTo(ms2.name); 1799 if (comp == 0) { 1800 comp = ms1.signature.compareTo(ms2.signature); 1801 } 1802 return comp; 1803 } 1804 }); 1805 for (int i = 0; i < methSigs.length; i++) { 1806 MemberSignature sig = methSigs[i]; 1807 int mods = sig.member.getModifiers() & 1808 (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED | 1809 Modifier.STATIC | Modifier.FINAL | 1810 Modifier.SYNCHRONIZED | Modifier.NATIVE | 1811 Modifier.ABSTRACT | Modifier.STRICT); 1812 if ((mods & Modifier.PRIVATE) == 0) { 1813 dout.writeUTF(sig.name); 1814 dout.writeInt(mods); 1815 dout.writeUTF(sig.signature.replace('/', '.')); 1816 } 1817 } 1818 1819 dout.flush(); 1820 1821 MessageDigest md = MessageDigest.getInstance("SHA"); 1822 byte[] hashBytes = md.digest(bout.toByteArray()); 1823 long hash = 0; 1824 for (int i = Math.min(hashBytes.length, 8) - 1; i >= 0; i--) { 1825 hash = (hash << 8) | (hashBytes[i] & 0xFF); 1826 } 1827 return hash; 1828 } catch (IOException ex) { 1829 throw new InternalError(ex); 1830 } catch (NoSuchAlgorithmException ex) { 1831 throw new SecurityException(ex.getMessage()); 1832 } 1833 } 1834 1835 /** 1836 * Returns true if the given class defines a static initializer method, 1837 * false otherwise. 1838 */ 1839 private static native boolean hasStaticInitializer(Class<?> cl); 1840 1841 /** 1842 * Class for computing and caching field/constructor/method signatures 1843 * during serialVersionUID calculation. 1844 */ 1845 private static class MemberSignature { 1846 1847 public final Member member; 1848 public final String name; 1849 public final String signature; 1850 1851 public MemberSignature(Field field) { 1852 member = field; 1853 name = field.getName(); 1854 signature = getClassSignature(field.getType()); 1855 } 1856 1857 public MemberSignature(Constructor<?> cons) { 1858 member = cons; 1859 name = cons.getName(); 1860 signature = getMethodSignature( 1861 cons.getParameterTypes(), Void.TYPE); 1862 } 1863 1864 public MemberSignature(Method meth) { 1865 member = meth; 1866 name = meth.getName(); 1867 signature = getMethodSignature( 1868 meth.getParameterTypes(), meth.getReturnType()); 1869 } 1870 } 1871 1872 /** 1873 * Class for setting and retrieving serializable field values in batch. 1874 */ 1875 // REMIND: dynamically generate these? 1876 private static class FieldReflector { 1877 1878 /** handle for performing unsafe operations */ 1879 private static final Unsafe unsafe = Unsafe.getUnsafe(); 1880 1881 /** fields to operate on */ 1882 private final ObjectStreamField[] fields; 1883 /** number of primitive fields */ 1884 private final int numPrimFields; 1885 /** unsafe field keys for reading fields - may contain dupes */ 1886 private final long[] readKeys; 1887 /** unsafe fields keys for writing fields - no dupes */ 1888 private final long[] writeKeys; 1889 /** field data offsets */ 1890 private final int[] offsets; 1891 /** field type codes */ 1892 private final char[] typeCodes; 1893 /** field types */ 1894 private final Class<?>[] types; 1895 1896 /** 1897 * Constructs FieldReflector capable of setting/getting values from the 1898 * subset of fields whose ObjectStreamFields contain non-null 1899 * reflective Field objects. ObjectStreamFields with null Fields are 1900 * treated as filler, for which get operations return default values 1901 * and set operations discard given values. 1902 */ 1903 FieldReflector(ObjectStreamField[] fields) { 1904 this.fields = fields; 1905 int nfields = fields.length; 1906 readKeys = new long[nfields]; 1907 writeKeys = new long[nfields]; 1908 offsets = new int[nfields]; 1909 typeCodes = new char[nfields]; 1910 ArrayList<Class<?>> typeList = new ArrayList<>(); 1911 Set<Long> usedKeys = new HashSet<>(); 1912 1913 1914 for (int i = 0; i < nfields; i++) { 1915 ObjectStreamField f = fields[i]; 1916 Field rf = f.getField(); 1917 long key = (rf != null) ? 1918 unsafe.objectFieldOffset(rf) : Unsafe.INVALID_FIELD_OFFSET; 1919 readKeys[i] = key; 1920 writeKeys[i] = usedKeys.add(key) ? 1921 key : Unsafe.INVALID_FIELD_OFFSET; 1922 offsets[i] = f.getOffset(); 1923 typeCodes[i] = f.getTypeCode(); 1924 if (!f.isPrimitive()) { 1925 typeList.add((rf != null) ? rf.getType() : null); 1926 } 1927 } 1928 1929 types = typeList.toArray(new Class<?>[typeList.size()]); 1930 numPrimFields = nfields - types.length; 1931 } 1932 1933 /** 1934 * Returns list of ObjectStreamFields representing fields operated on 1935 * by this reflector. The shared/unshared values and Field objects 1936 * contained by ObjectStreamFields in the list reflect their bindings 1937 * to locally defined serializable fields. 1938 */ 1939 ObjectStreamField[] getFields() { 1940 return fields; 1941 } 1942 1943 /** 1944 * Fetches the serializable primitive field values of object obj and 1945 * marshals them into byte array buf starting at offset 0. The caller 1946 * is responsible for ensuring that obj is of the proper type. 1947 */ 1948 void getPrimFieldValues(Object obj, byte[] buf) { 1949 if (obj == null) { 1950 throw new NullPointerException(); 1951 } 1952 /* assuming checkDefaultSerialize() has been called on the class 1953 * descriptor this FieldReflector was obtained from, no field keys 1954 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET. 1955 */ 1956 for (int i = 0; i < numPrimFields; i++) { 1957 long key = readKeys[i]; 1958 int off = offsets[i]; 1959 switch (typeCodes[i]) { 1960 case 'Z': 1961 Bits.putBoolean(buf, off, unsafe.getBoolean(obj, key)); 1962 break; 1963 1964 case 'B': 1965 buf[off] = unsafe.getByte(obj, key); 1966 break; 1967 1968 case 'C': 1969 Bits.putChar(buf, off, unsafe.getChar(obj, key)); 1970 break; 1971 1972 case 'S': 1973 Bits.putShort(buf, off, unsafe.getShort(obj, key)); 1974 break; 1975 1976 case 'I': 1977 Bits.putInt(buf, off, unsafe.getInt(obj, key)); 1978 break; 1979 1980 case 'F': 1981 Bits.putFloat(buf, off, unsafe.getFloat(obj, key)); 1982 break; 1983 1984 case 'J': 1985 Bits.putLong(buf, off, unsafe.getLong(obj, key)); 1986 break; 1987 1988 case 'D': 1989 Bits.putDouble(buf, off, unsafe.getDouble(obj, key)); 1990 break; 1991 1992 default: 1993 throw new InternalError(); 1994 } 1995 } 1996 } 1997 1998 /** 1999 * Sets the serializable primitive fields of object obj using values 2000 * unmarshalled from byte array buf starting at offset 0. The caller 2001 * is responsible for ensuring that obj is of the proper type. 2002 */ 2003 void setPrimFieldValues(Object obj, byte[] buf) { 2004 if (obj == null) { 2005 throw new NullPointerException(); 2006 } 2007 for (int i = 0; i < numPrimFields; i++) { 2008 long key = writeKeys[i]; 2009 if (key == Unsafe.INVALID_FIELD_OFFSET) { 2010 continue; // discard value 2011 } 2012 int off = offsets[i]; 2013 switch (typeCodes[i]) { 2014 case 'Z': 2015 unsafe.putBoolean(obj, key, Bits.getBoolean(buf, off)); 2016 break; 2017 2018 case 'B': 2019 unsafe.putByte(obj, key, buf[off]); 2020 break; 2021 2022 case 'C': 2023 unsafe.putChar(obj, key, Bits.getChar(buf, off)); 2024 break; 2025 2026 case 'S': 2027 unsafe.putShort(obj, key, Bits.getShort(buf, off)); 2028 break; 2029 2030 case 'I': 2031 unsafe.putInt(obj, key, Bits.getInt(buf, off)); 2032 break; 2033 2034 case 'F': 2035 unsafe.putFloat(obj, key, Bits.getFloat(buf, off)); 2036 break; 2037 2038 case 'J': 2039 unsafe.putLong(obj, key, Bits.getLong(buf, off)); 2040 break; 2041 2042 case 'D': 2043 unsafe.putDouble(obj, key, Bits.getDouble(buf, off)); 2044 break; 2045 2046 default: 2047 throw new InternalError(); 2048 } 2049 } 2050 } 2051 2052 /** 2053 * Fetches the serializable object field values of object obj and 2054 * stores them in array vals starting at offset 0. The caller is 2055 * responsible for ensuring that obj is of the proper type. 2056 */ 2057 void getObjFieldValues(Object obj, Object[] vals) { 2058 if (obj == null) { 2059 throw new NullPointerException(); 2060 } 2061 /* assuming checkDefaultSerialize() has been called on the class 2062 * descriptor this FieldReflector was obtained from, no field keys 2063 * in array should be equal to Unsafe.INVALID_FIELD_OFFSET. 2064 */ 2065 for (int i = numPrimFields; i < fields.length; i++) { 2066 switch (typeCodes[i]) { 2067 case 'L': 2068 case '[': 2069 vals[offsets[i]] = unsafe.getObject(obj, readKeys[i]); 2070 break; 2071 2072 default: 2073 throw new InternalError(); 2074 } 2075 } 2076 } 2077 2078 /** 2079 * Checks that the given values, from array vals starting at offset 0, 2080 * are assignable to the given serializable object fields. 2081 * @throws ClassCastException if any value is not assignable 2082 */ 2083 void checkObjectFieldValueTypes(Object obj, Object[] vals) { 2084 setObjFieldValues(obj, vals, true); 2085 } 2086 2087 /** 2088 * Sets the serializable object fields of object obj using values from 2089 * array vals starting at offset 0. The caller is responsible for 2090 * ensuring that obj is of the proper type; however, attempts to set a 2091 * field with a value of the wrong type will trigger an appropriate 2092 * ClassCastException. 2093 */ 2094 void setObjFieldValues(Object obj, Object[] vals) { 2095 setObjFieldValues(obj, vals, false); 2096 } 2097 2098 private void setObjFieldValues(Object obj, Object[] vals, boolean dryRun) { 2099 if (obj == null) { 2100 throw new NullPointerException(); 2101 } 2102 for (int i = numPrimFields; i < fields.length; i++) { 2103 long key = writeKeys[i]; 2104 if (key == Unsafe.INVALID_FIELD_OFFSET) { 2105 continue; // discard value 2106 } 2107 switch (typeCodes[i]) { 2108 case 'L': 2109 case '[': 2110 Object val = vals[offsets[i]]; 2111 if (val != null && 2112 !types[i - numPrimFields].isInstance(val)) 2113 { 2114 Field f = fields[i].getField(); 2115 throw new ClassCastException( 2116 "cannot assign instance of " + 2117 val.getClass().getName() + " to field " + 2118 f.getDeclaringClass().getName() + "." + 2119 f.getName() + " of type " + 2120 f.getType().getName() + " in instance of " + 2121 obj.getClass().getName()); 2122 } 2123 if (!dryRun) 2124 unsafe.putObject(obj, key, val); 2125 break; 2126 2127 default: 2128 throw new InternalError(); 2129 } 2130 } 2131 } 2132 } 2133 2134 /** 2135 * Matches given set of serializable fields with serializable fields 2136 * described by the given local class descriptor, and returns a 2137 * FieldReflector instance capable of setting/getting values from the 2138 * subset of fields that match (non-matching fields are treated as filler, 2139 * for which get operations return default values and set operations 2140 * discard given values). Throws InvalidClassException if unresolvable 2141 * type conflicts exist between the two sets of fields. 2142 */ 2143 private static FieldReflector getReflector(ObjectStreamField[] fields, 2144 ObjectStreamClass localDesc) 2145 throws InvalidClassException 2146 { 2147 // class irrelevant if no fields 2148 Class<?> cl = (localDesc != null && fields.length > 0) ? 2149 localDesc.cl : null; 2150 processQueue(Caches.reflectorsQueue, Caches.reflectors); 2151 FieldReflectorKey key = new FieldReflectorKey(cl, fields, 2152 Caches.reflectorsQueue); 2153 Reference<?> ref = Caches.reflectors.get(key); 2154 Object entry = null; 2155 if (ref != null) { 2156 entry = ref.get(); 2157 } 2158 EntryFuture future = null; 2159 if (entry == null) { 2160 EntryFuture newEntry = new EntryFuture(); 2161 Reference<?> newRef = new SoftReference<>(newEntry); 2162 do { 2163 if (ref != null) { 2164 Caches.reflectors.remove(key, ref); 2165 } 2166 ref = Caches.reflectors.putIfAbsent(key, newRef); 2167 if (ref != null) { 2168 entry = ref.get(); 2169 } 2170 } while (ref != null && entry == null); 2171 if (entry == null) { 2172 future = newEntry; 2173 } 2174 } 2175 2176 if (entry instanceof FieldReflector) { // check common case first 2177 return (FieldReflector) entry; 2178 } else if (entry instanceof EntryFuture) { 2179 entry = ((EntryFuture) entry).get(); 2180 } else if (entry == null) { 2181 try { 2182 entry = new FieldReflector(matchFields(fields, localDesc)); 2183 } catch (Throwable th) { 2184 entry = th; 2185 } 2186 future.set(entry); 2187 Caches.reflectors.put(key, new SoftReference<>(entry)); 2188 } 2189 2190 if (entry instanceof FieldReflector) { 2191 return (FieldReflector) entry; 2192 } else if (entry instanceof InvalidClassException) { 2193 throw (InvalidClassException) entry; 2194 } else if (entry instanceof RuntimeException) { 2195 throw (RuntimeException) entry; 2196 } else if (entry instanceof Error) { 2197 throw (Error) entry; 2198 } else { 2199 throw new InternalError("unexpected entry: " + entry); 2200 } 2201 } 2202 2203 /** 2204 * FieldReflector cache lookup key. Keys are considered equal if they 2205 * refer to the same class and equivalent field formats. 2206 */ 2207 private static class FieldReflectorKey extends WeakReference<Class<?>> { 2208 2209 private final String sigs; 2210 private final int hash; 2211 private final boolean nullClass; 2212 2213 FieldReflectorKey(Class<?> cl, ObjectStreamField[] fields, 2214 ReferenceQueue<Class<?>> queue) 2215 { 2216 super(cl, queue); 2217 nullClass = (cl == null); 2218 StringBuilder sbuf = new StringBuilder(); 2219 for (int i = 0; i < fields.length; i++) { 2220 ObjectStreamField f = fields[i]; 2221 sbuf.append(f.getName()).append(f.getSignature()); 2222 } 2223 sigs = sbuf.toString(); 2224 hash = System.identityHashCode(cl) + sigs.hashCode(); 2225 } 2226 2227 public int hashCode() { 2228 return hash; 2229 } 2230 2231 public boolean equals(Object obj) { 2232 if (obj == this) { 2233 return true; 2234 } 2235 2236 if (obj instanceof FieldReflectorKey) { 2237 FieldReflectorKey other = (FieldReflectorKey) obj; 2238 Class<?> referent; 2239 return (nullClass ? other.nullClass 2240 : ((referent = get()) != null) && 2241 (referent == other.get())) && 2242 sigs.equals(other.sigs); 2243 } else { 2244 return false; 2245 } 2246 } 2247 } 2248 2249 /** 2250 * Matches given set of serializable fields with serializable fields 2251 * obtained from the given local class descriptor (which contain bindings 2252 * to reflective Field objects). Returns list of ObjectStreamFields in 2253 * which each ObjectStreamField whose signature matches that of a local 2254 * field contains a Field object for that field; unmatched 2255 * ObjectStreamFields contain null Field objects. Shared/unshared settings 2256 * of the returned ObjectStreamFields also reflect those of matched local 2257 * ObjectStreamFields. Throws InvalidClassException if unresolvable type 2258 * conflicts exist between the two sets of fields. 2259 */ 2260 private static ObjectStreamField[] matchFields(ObjectStreamField[] fields, 2261 ObjectStreamClass localDesc) 2262 throws InvalidClassException 2263 { 2264 ObjectStreamField[] localFields = (localDesc != null) ? 2265 localDesc.fields : NO_FIELDS; 2266 2267 /* 2268 * Even if fields == localFields, we cannot simply return localFields 2269 * here. In previous implementations of serialization, 2270 * ObjectStreamField.getType() returned Object.class if the 2271 * ObjectStreamField represented a non-primitive field and belonged to 2272 * a non-local class descriptor. To preserve this (questionable) 2273 * behavior, the ObjectStreamField instances returned by matchFields 2274 * cannot report non-primitive types other than Object.class; hence 2275 * localFields cannot be returned directly. 2276 */ 2277 2278 ObjectStreamField[] matches = new ObjectStreamField[fields.length]; 2279 for (int i = 0; i < fields.length; i++) { 2280 ObjectStreamField f = fields[i], m = null; 2281 for (int j = 0; j < localFields.length; j++) { 2282 ObjectStreamField lf = localFields[j]; 2283 if (f.getName().equals(lf.getName())) { 2284 if ((f.isPrimitive() || lf.isPrimitive()) && 2285 f.getTypeCode() != lf.getTypeCode()) 2286 { 2287 throw new InvalidClassException(localDesc.name, 2288 "incompatible types for field " + f.getName()); 2289 } 2290 if (lf.getField() != null) { 2291 m = new ObjectStreamField( 2292 lf.getField(), lf.isUnshared(), false); 2293 } else { 2294 m = new ObjectStreamField( 2295 lf.getName(), lf.getSignature(), lf.isUnshared()); 2296 } 2297 } 2298 } 2299 if (m == null) { 2300 m = new ObjectStreamField( 2301 f.getName(), f.getSignature(), false); 2302 } 2303 m.setOffset(f.getOffset()); 2304 matches[i] = m; 2305 } 2306 return matches; 2307 } 2308 2309 /** 2310 * Removes from the specified map any keys that have been enqueued 2311 * on the specified reference queue. 2312 */ 2313 static void processQueue(ReferenceQueue<Class<?>> queue, 2314 ConcurrentMap<? extends 2315 WeakReference<Class<?>>, ?> map) 2316 { 2317 Reference<? extends Class<?>> ref; 2318 while((ref = queue.poll()) != null) { 2319 map.remove(ref); 2320 } 2321 } 2322 2323 /** 2324 * Weak key for Class objects. 2325 * 2326 **/ 2327 static class WeakClassKey extends WeakReference<Class<?>> { 2328 /** 2329 * saved value of the referent's identity hash code, to maintain 2330 * a consistent hash code after the referent has been cleared 2331 */ 2332 private final int hash; 2333 2334 /** 2335 * Create a new WeakClassKey to the given object, registered 2336 * with a queue. 2337 */ 2338 WeakClassKey(Class<?> cl, ReferenceQueue<Class<?>> refQueue) { 2339 super(cl, refQueue); 2340 hash = System.identityHashCode(cl); 2341 } 2342 2343 /** 2344 * Returns the identity hash code of the original referent. 2345 */ 2346 public int hashCode() { 2347 return hash; 2348 } 2349 2350 /** 2351 * Returns true if the given object is this identical 2352 * WeakClassKey instance, or, if this object's referent has not 2353 * been cleared, if the given object is another WeakClassKey 2354 * instance with the identical non-null referent as this one. 2355 */ 2356 public boolean equals(Object obj) { 2357 if (obj == this) { 2358 return true; 2359 } 2360 2361 if (obj instanceof WeakClassKey) { 2362 Object referent = get(); 2363 return (referent != null) && 2364 (referent == ((WeakClassKey) obj).get()); 2365 } else { 2366 return false; 2367 } 2368 } 2369 } 2370 }