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.security.AccessController; 29 import java.security.PrivilegedAction; 30 import java.util.ArrayList; 31 import java.util.Arrays; 32 import java.util.List; 33 import java.util.Objects; 34 import java.util.StringJoiner; 35 import sun.reflect.misc.ReflectUtil; 36 37 /** 38 * An ObjectOutputStream writes primitive data types and graphs of Java objects 39 * to an OutputStream. The objects can be read (reconstituted) using an 40 * ObjectInputStream. Persistent storage of objects can be accomplished by 41 * using a file for the stream. If the stream is a network socket stream, the 42 * objects can be reconstituted on another host or in another process. 43 * 44 * <p>Only objects that support the java.io.Serializable interface can be 45 * written to streams. The class of each serializable object is encoded 46 * including the class name and signature of the class, the values of the 47 * object's fields and arrays, and the closure of any other objects referenced 48 * from the initial objects. 49 * 50 * <p>The method writeObject is used to write an object to the stream. Any 51 * object, including Strings and arrays, is written with writeObject. Multiple 52 * objects or primitives can be written to the stream. The objects must be 53 * read back from the corresponding ObjectInputstream with the same types and 54 * in the same order as they were written. 55 * 56 * <p>Primitive data types can also be written to the stream using the 57 * appropriate methods from DataOutput. Strings can also be written using the 58 * writeUTF method. 59 * 60 * <p>The default serialization mechanism for an object writes the class of the 61 * object, the class signature, and the values of all non-transient and 62 * non-static fields. References to other objects (except in transient or 63 * static fields) cause those objects to be written also. Multiple references 64 * to a single object are encoded using a reference sharing mechanism so that 65 * graphs of objects can be restored to the same shape as when the original was 66 * written. 67 * 68 * <p>For example to write an object that can be read by the example in 69 * ObjectInputStream: 70 * <br> 71 * <pre> 72 * FileOutputStream fos = new FileOutputStream("t.tmp"); 73 * ObjectOutputStream oos = new ObjectOutputStream(fos); 74 * 75 * oos.writeInt(12345); 76 * oos.writeObject("Today"); 77 * oos.writeObject(new Date()); 78 * 79 * oos.close(); 80 * </pre> 81 * 82 * <p>Serializable classes that require special handling during the 83 * serialization and deserialization process should implement methods 84 * with the following signatures: 85 * 86 * <br> 87 * <pre> 88 * private void readObject(java.io.ObjectInputStream stream) 89 * throws IOException, ClassNotFoundException; 90 * private void writeObject(java.io.ObjectOutputStream stream) 91 * throws IOException 92 * private void readObjectNoData() 93 * throws ObjectStreamException; 94 * </pre> 95 * 96 * <p>The method name, modifiers, return type, and number and type of 97 * parameters must match exactly for the method to be used by 98 * serialization or deserialization. The methods should only be 99 * declared to throw checked exceptions consistent with these 100 * signatures. 101 * 102 * <p>The writeObject method is responsible for writing the state of the object 103 * for its particular class so that the corresponding readObject method can 104 * restore it. The method does not need to concern itself with the state 105 * belonging to the object's superclasses or subclasses. State is saved by 106 * writing the individual fields to the ObjectOutputStream using the 107 * writeObject method or by using the methods for primitive data types 108 * supported by DataOutput. 109 * 110 * <p>Serialization does not write out the fields of any object that does not 111 * implement the java.io.Serializable interface. Subclasses of Objects that 112 * are not serializable can be serializable. In this case the non-serializable 113 * class must have a no-arg constructor to allow its fields to be initialized. 114 * In this case it is the responsibility of the subclass to save and restore 115 * the state of the non-serializable class. It is frequently the case that the 116 * fields of that class are accessible (public, package, or protected) or that 117 * there are get and set methods that can be used to restore the state. 118 * 119 * <p>Serialization of an object can be prevented by implementing writeObject 120 * and readObject methods that throw the NotSerializableException. The 121 * exception will be caught by the ObjectOutputStream and abort the 122 * serialization process. 123 * 124 * <p>Implementing the Externalizable interface allows the object to assume 125 * complete control over the contents and format of the object's serialized 126 * form. The methods of the Externalizable interface, writeExternal and 127 * readExternal, are called to save and restore the objects state. When 128 * implemented by a class they can write and read their own state using all of 129 * the methods of ObjectOutput and ObjectInput. It is the responsibility of 130 * the objects to handle any versioning that occurs. 131 * 132 * <p>Enum constants are serialized differently than ordinary serializable or 133 * externalizable objects. The serialized form of an enum constant consists 134 * solely of its name; field values of the constant are not transmitted. To 135 * serialize an enum constant, ObjectOutputStream writes the string returned by 136 * the constant's name method. Like other serializable or externalizable 137 * objects, enum constants can function as the targets of back references 138 * appearing subsequently in the serialization stream. The process by which 139 * enum constants are serialized cannot be customized; any class-specific 140 * writeObject and writeReplace methods defined by enum types are ignored 141 * during serialization. Similarly, any serialPersistentFields or 142 * serialVersionUID field declarations are also ignored--all enum types have a 143 * fixed serialVersionUID of 0L. 144 * 145 * <p>Primitive data, excluding serializable fields and externalizable data, is 146 * written to the ObjectOutputStream in block-data records. A block data record 147 * is composed of a header and data. The block data header consists of a marker 148 * and the number of bytes to follow the header. Consecutive primitive data 149 * writes are merged into one block-data record. The blocking factor used for 150 * a block-data record will be 1024 bytes. Each block-data record will be 151 * filled up to 1024 bytes, or be written whenever there is a termination of 152 * block-data mode. Calls to the ObjectOutputStream methods writeObject, 153 * defaultWriteObject and writeFields initially terminate any existing 154 * block-data record. 155 * 156 * <p>Records are serialized differently than ordinary serializable or externalizable 157 * objects, see <a href="ObjectInputStream.html#record-serialization">record serialization</a>. 158 * 159 * @author Mike Warres 160 * @author Roger Riggs 161 * @see java.io.DataOutput 162 * @see java.io.ObjectInputStream 163 * @see java.io.Serializable 164 * @see java.io.Externalizable 165 * @see <a href="{@docRoot}/../specs/serialization/output.html"> 166 * <cite>Java Object Serialization Specification,</cite> Section 2, "Object Output Classes"</a> 167 * @since 1.1 168 */ 169 public class ObjectOutputStream 170 extends OutputStream implements ObjectOutput, ObjectStreamConstants 171 { 172 173 private static class Caches { 174 /** cache of subclass security audit results */ 175 static final ClassValue<Boolean> subclassAudits = 176 new ClassValue<>() { 177 @Override 178 protected Boolean computeValue(Class<?> type) { 179 return auditSubclass(type); 180 } 181 }; 182 } 183 184 /** filter stream for handling block data conversion */ 185 private final BlockDataOutputStream bout; 186 /** obj -> wire handle map */ 187 private final HandleTable handles; 188 /** obj -> replacement obj map */ 189 private final ReplaceTable subs; 190 /** stream protocol version */ 191 private int protocol = PROTOCOL_VERSION_2; 192 /** recursion depth */ 193 private int depth; 194 195 /** buffer for writing primitive field values */ 196 private byte[] primVals; 197 198 /** if true, invoke writeObjectOverride() instead of writeObject() */ 199 private final boolean enableOverride; 200 /** if true, invoke replaceObject() */ 201 private boolean enableReplace; 202 203 // values below valid only during upcalls to writeObject()/writeExternal() 204 /** 205 * Context during upcalls to class-defined writeObject methods; holds 206 * object currently being serialized and descriptor for current class. 207 * Null when not during writeObject upcall. 208 */ 209 private SerialCallbackContext curContext; 210 /** current PutField object */ 211 private PutFieldImpl curPut; 212 213 /** custom storage for debug trace info */ 214 private final DebugTraceInfoStack debugInfoStack; 215 216 /** 217 * value of "sun.io.serialization.extendedDebugInfo" property, 218 * as true or false for extended information about exception's place 219 */ 220 @SuppressWarnings("removal") 221 private static final boolean extendedDebugInfo = 222 java.security.AccessController.doPrivileged( 223 new sun.security.action.GetBooleanAction( 224 "sun.io.serialization.extendedDebugInfo")).booleanValue(); 225 226 /** 227 * Creates an ObjectOutputStream that writes to the specified OutputStream. 228 * This constructor writes the serialization stream header to the 229 * underlying stream; callers may wish to flush the stream immediately to 230 * ensure that constructors for receiving ObjectInputStreams will not block 231 * when reading the header. 232 * 233 * <p>If a security manager is installed, this constructor will check for 234 * the "enableSubclassImplementation" SerializablePermission when invoked 235 * directly or indirectly by the constructor of a subclass which overrides 236 * the ObjectOutputStream.putFields or ObjectOutputStream.writeUnshared 237 * methods. 238 * 239 * @param out output stream to write to 240 * @throws IOException if an I/O error occurs while writing stream header 241 * @throws SecurityException if untrusted subclass illegally overrides 242 * security-sensitive methods 243 * @throws NullPointerException if {@code out} is {@code null} 244 * @since 1.4 245 * @see ObjectOutputStream#ObjectOutputStream() 246 * @see ObjectOutputStream#putFields() 247 * @see ObjectInputStream#ObjectInputStream(InputStream) 248 */ 249 public ObjectOutputStream(OutputStream out) throws IOException { 250 verifySubclass(); 251 bout = new BlockDataOutputStream(out); 252 handles = new HandleTable(10, (float) 3.00); 253 subs = new ReplaceTable(10, (float) 3.00); 254 enableOverride = false; 255 writeStreamHeader(); 256 bout.setBlockDataMode(true); 257 if (extendedDebugInfo) { 258 debugInfoStack = new DebugTraceInfoStack(); 259 } else { 260 debugInfoStack = null; 261 } 262 } 263 264 /** 265 * Provide a way for subclasses that are completely reimplementing 266 * ObjectOutputStream to not have to allocate private data just used by 267 * this implementation of ObjectOutputStream. 268 * 269 * <p>If there is a security manager installed, this method first calls the 270 * security manager's {@code checkPermission} method with a 271 * {@code SerializablePermission("enableSubclassImplementation")} 272 * permission to ensure it's ok to enable subclassing. 273 * 274 * @throws SecurityException if a security manager exists and its 275 * {@code checkPermission} method denies enabling 276 * subclassing. 277 * @throws IOException if an I/O error occurs while creating this stream 278 * @see SecurityManager#checkPermission 279 * @see java.io.SerializablePermission 280 */ 281 protected ObjectOutputStream() throws IOException, SecurityException { 282 @SuppressWarnings("removal") 283 SecurityManager sm = System.getSecurityManager(); 284 if (sm != null) { 285 sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION); 286 } 287 bout = null; 288 handles = null; 289 subs = null; 290 enableOverride = true; 291 debugInfoStack = null; 292 } 293 294 /** 295 * Specify stream protocol version to use when writing the stream. 296 * 297 * <p>This routine provides a hook to enable the current version of 298 * Serialization to write in a format that is backwards compatible to a 299 * previous version of the stream format. 300 * 301 * <p>Every effort will be made to avoid introducing additional 302 * backwards incompatibilities; however, sometimes there is no 303 * other alternative. 304 * 305 * @param version use ProtocolVersion from java.io.ObjectStreamConstants. 306 * @throws IllegalStateException if called after any objects 307 * have been serialized. 308 * @throws IllegalArgumentException if invalid version is passed in. 309 * @throws IOException if I/O errors occur 310 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_1 311 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_2 312 * @since 1.2 313 */ 314 public void useProtocolVersion(int version) throws IOException { 315 if (handles.size() != 0) { 316 // REMIND: implement better check for pristine stream? 317 throw new IllegalStateException("stream non-empty"); 318 } 319 switch (version) { 320 case PROTOCOL_VERSION_1: 321 case PROTOCOL_VERSION_2: 322 protocol = version; 323 break; 324 325 default: 326 throw new IllegalArgumentException( 327 "unknown version: " + version); 328 } 329 } 330 331 /** 332 * Write the specified object to the ObjectOutputStream. The class of the 333 * object, the signature of the class, and the values of the non-transient 334 * and non-static fields of the class and all of its supertypes are 335 * written. Default serialization for a class can be overridden using the 336 * writeObject and the readObject methods. Objects referenced by this 337 * object are written transitively so that a complete equivalent graph of 338 * objects can be reconstructed by an ObjectInputStream. 339 * 340 * <p>Exceptions are thrown for problems with the OutputStream and for 341 * classes that should not be serialized. All exceptions are fatal to the 342 * OutputStream, which is left in an indeterminate state, and it is up to 343 * the caller to ignore or recover the stream state. 344 * 345 * @throws InvalidClassException Something is wrong with a class used by 346 * serialization. 347 * @throws NotSerializableException Some object to be serialized does not 348 * implement the java.io.Serializable interface. 349 * @throws IOException Any exception thrown by the underlying 350 * OutputStream. 351 */ 352 public final void writeObject(Object obj) throws IOException { 353 if (enableOverride) { 354 writeObjectOverride(obj); 355 return; 356 } 357 try { 358 writeObject0(obj, false); 359 } catch (IOException ex) { 360 if (depth == 0) { 361 writeFatalException(ex); 362 } 363 throw ex; 364 } 365 } 366 367 /** 368 * Method used by subclasses to override the default writeObject method. 369 * This method is called by trusted subclasses of ObjectOutputStream that 370 * constructed ObjectOutputStream using the protected no-arg constructor. 371 * The subclass is expected to provide an override method with the modifier 372 * "final". 373 * 374 * @param obj object to be written to the underlying stream 375 * @throws IOException if there are I/O errors while writing to the 376 * underlying stream 377 * @see #ObjectOutputStream() 378 * @see #writeObject(Object) 379 * @since 1.2 380 */ 381 protected void writeObjectOverride(Object obj) throws IOException { 382 } 383 384 /** 385 * Writes an "unshared" object to the ObjectOutputStream. This method is 386 * identical to writeObject, except that it always writes the given object 387 * as a new, unique object in the stream (as opposed to a back-reference 388 * pointing to a previously serialized instance). Specifically: 389 * <ul> 390 * <li>An object written via writeUnshared is always serialized in the 391 * same manner as a newly appearing object (an object that has not 392 * been written to the stream yet), regardless of whether or not the 393 * object has been written previously. 394 * 395 * <li>If writeObject is used to write an object that has been previously 396 * written with writeUnshared, the previous writeUnshared operation 397 * is treated as if it were a write of a separate object. In other 398 * words, ObjectOutputStream will never generate back-references to 399 * object data written by calls to writeUnshared. 400 * </ul> 401 * While writing an object via writeUnshared does not in itself guarantee a 402 * unique reference to the object when it is deserialized, it allows a 403 * single object to be defined multiple times in a stream, so that multiple 404 * calls to readUnshared by the receiver will not conflict. Note that the 405 * rules described above only apply to the base-level object written with 406 * writeUnshared, and not to any transitively referenced sub-objects in the 407 * object graph to be serialized. 408 * 409 * <p>ObjectOutputStream subclasses which override this method can only be 410 * constructed in security contexts possessing the 411 * "enableSubclassImplementation" SerializablePermission; any attempt to 412 * instantiate such a subclass without this permission will cause a 413 * SecurityException to be thrown. 414 * 415 * @param obj object to write to stream 416 * @throws NotSerializableException if an object in the graph to be 417 * serialized does not implement the Serializable interface 418 * @throws InvalidClassException if a problem exists with the class of an 419 * object to be serialized 420 * @throws IOException if an I/O error occurs during serialization 421 * @since 1.4 422 */ 423 public void writeUnshared(Object obj) throws IOException { 424 try { 425 writeObject0(obj, true); 426 } catch (IOException ex) { 427 if (depth == 0) { 428 writeFatalException(ex); 429 } 430 throw ex; 431 } 432 } 433 434 /** 435 * Write the non-static and non-transient fields of the current class to 436 * this stream. This may only be called from the writeObject method of the 437 * class being serialized. It will throw the NotActiveException if it is 438 * called otherwise. 439 * 440 * @throws IOException if I/O errors occur while writing to the underlying 441 * {@code OutputStream} 442 */ 443 public void defaultWriteObject() throws IOException { 444 SerialCallbackContext ctx = curContext; 445 if (ctx == null) { 446 throw new NotActiveException("not in call to writeObject"); 447 } 448 Object curObj = ctx.getObj(); 449 ObjectStreamClass curDesc = ctx.getDesc(); 450 bout.setBlockDataMode(false); 451 defaultWriteFields(curObj, curDesc); 452 bout.setBlockDataMode(true); 453 } 454 455 /** 456 * Retrieve the object used to buffer persistent fields to be written to 457 * the stream. The fields will be written to the stream when writeFields 458 * method is called. 459 * 460 * @return an instance of the class Putfield that holds the serializable 461 * fields 462 * @throws IOException if I/O errors occur 463 * @since 1.2 464 */ 465 public ObjectOutputStream.PutField putFields() throws IOException { 466 if (curPut == null) { 467 SerialCallbackContext ctx = curContext; 468 if (ctx == null) { 469 throw new NotActiveException("not in call to writeObject"); 470 } 471 ctx.checkAndSetUsed(); 472 ObjectStreamClass curDesc = ctx.getDesc(); 473 curPut = new PutFieldImpl(curDesc); 474 } 475 return curPut; 476 } 477 478 /** 479 * Write the buffered fields to the stream. 480 * 481 * @throws IOException if I/O errors occur while writing to the underlying 482 * stream 483 * @throws NotActiveException Called when a classes writeObject method was 484 * not called to write the state of the object. 485 * @since 1.2 486 */ 487 public void writeFields() throws IOException { 488 if (curPut == null) { 489 throw new NotActiveException("no current PutField object"); 490 } 491 bout.setBlockDataMode(false); 492 curPut.writeFields(); 493 bout.setBlockDataMode(true); 494 } 495 496 /** 497 * Reset will disregard the state of any objects already written to the 498 * stream. The state is reset to be the same as a new ObjectOutputStream. 499 * The current point in the stream is marked as reset so the corresponding 500 * ObjectInputStream will be reset at the same point. Objects previously 501 * written to the stream will not be referred to as already being in the 502 * stream. They will be written to the stream again. 503 * 504 * @throws IOException if reset() is invoked while serializing an object. 505 */ 506 public void reset() throws IOException { 507 if (depth != 0) { 508 throw new IOException("stream active"); 509 } 510 bout.setBlockDataMode(false); 511 bout.writeByte(TC_RESET); 512 clear(); 513 bout.setBlockDataMode(true); 514 } 515 516 /** 517 * Subclasses may implement this method to allow class data to be stored in 518 * the stream. By default this method does nothing. The corresponding 519 * method in ObjectInputStream is resolveClass. This method is called 520 * exactly once for each unique class in the stream. The class name and 521 * signature will have already been written to the stream. This method may 522 * make free use of the ObjectOutputStream to save any representation of 523 * the class it deems suitable (for example, the bytes of the class file). 524 * The resolveClass method in the corresponding subclass of 525 * ObjectInputStream must read and use any data or objects written by 526 * annotateClass. 527 * 528 * @param cl the class to annotate custom data for 529 * @throws IOException Any exception thrown by the underlying 530 * OutputStream. 531 */ 532 protected void annotateClass(Class<?> cl) throws IOException { 533 } 534 535 /** 536 * Subclasses may implement this method to store custom data in the stream 537 * along with descriptors for dynamic proxy classes. 538 * 539 * <p>This method is called exactly once for each unique proxy class 540 * descriptor in the stream. The default implementation of this method in 541 * {@code ObjectOutputStream} does nothing. 542 * 543 * <p>The corresponding method in {@code ObjectInputStream} is 544 * {@code resolveProxyClass}. For a given subclass of 545 * {@code ObjectOutputStream} that overrides this method, the 546 * {@code resolveProxyClass} method in the corresponding subclass of 547 * {@code ObjectInputStream} must read any data or objects written by 548 * {@code annotateProxyClass}. 549 * 550 * @param cl the proxy class to annotate custom data for 551 * @throws IOException any exception thrown by the underlying 552 * {@code OutputStream} 553 * @see ObjectInputStream#resolveProxyClass(String[]) 554 * @since 1.3 555 */ 556 protected void annotateProxyClass(Class<?> cl) throws IOException { 557 } 558 559 /** 560 * This method will allow trusted subclasses of ObjectOutputStream to 561 * substitute one object for another during serialization. Replacing 562 * objects is disabled until enableReplaceObject is called. The 563 * enableReplaceObject method checks that the stream requesting to do 564 * replacement can be trusted. The first occurrence of each object written 565 * into the serialization stream is passed to replaceObject. Subsequent 566 * references to the object are replaced by the object returned by the 567 * original call to replaceObject. To ensure that the private state of 568 * objects is not unintentionally exposed, only trusted streams may use 569 * replaceObject. 570 * 571 * <p>The ObjectOutputStream.writeObject method takes a parameter of type 572 * Object (as opposed to type Serializable) to allow for cases where 573 * non-serializable objects are replaced by serializable ones. 574 * 575 * <p>When a subclass is replacing objects it must ensure that either a 576 * complementary substitution must be made during deserialization or that 577 * the substituted object is compatible with every field where the 578 * reference will be stored. Objects whose type is not a subclass of the 579 * type of the field or array element abort the serialization by raising an 580 * exception and the object is not be stored. 581 * 582 * <p>This method is called only once when each object is first 583 * encountered. All subsequent references to the object will be redirected 584 * to the new object. This method should return the object to be 585 * substituted or the original object. 586 * 587 * <p>Null can be returned as the object to be substituted, but may cause 588 * NullReferenceException in classes that contain references to the 589 * original object since they may be expecting an object instead of 590 * null. 591 * 592 * @param obj the object to be replaced 593 * @return the alternate object that replaced the specified one 594 * @throws IOException Any exception thrown by the underlying 595 * OutputStream. 596 */ 597 protected Object replaceObject(Object obj) throws IOException { 598 return obj; 599 } 600 601 /** 602 * Enables the stream to do replacement of objects written to the stream. When 603 * enabled, the {@link #replaceObject} method is called for every object being 604 * serialized. 605 * 606 * <p>If object replacement is currently not enabled, and 607 * {@code enable} is true, and there is a security manager installed, 608 * this method first calls the security manager's 609 * {@code checkPermission} method with the 610 * {@code SerializablePermission("enableSubstitution")} permission to 611 * ensure that the caller is permitted to enable the stream to do replacement 612 * of objects written to the stream. 613 * 614 * @param enable true for enabling use of {@code replaceObject} for 615 * every object being serialized 616 * @return the previous setting before this method was invoked 617 * @throws SecurityException if a security manager exists and its 618 * {@code checkPermission} method denies enabling the stream 619 * to do replacement of objects written to the stream. 620 * @see SecurityManager#checkPermission 621 * @see java.io.SerializablePermission 622 */ 623 protected boolean enableReplaceObject(boolean enable) 624 throws SecurityException 625 { 626 if (enable == enableReplace) { 627 return enable; 628 } 629 if (enable) { 630 @SuppressWarnings("removal") 631 SecurityManager sm = System.getSecurityManager(); 632 if (sm != null) { 633 sm.checkPermission(SUBSTITUTION_PERMISSION); 634 } 635 } 636 enableReplace = enable; 637 return !enableReplace; 638 } 639 640 /** 641 * The writeStreamHeader method is provided so subclasses can append or 642 * prepend their own header to the stream. It writes the magic number and 643 * version to the stream. 644 * 645 * @throws IOException if I/O errors occur while writing to the underlying 646 * stream 647 */ 648 protected void writeStreamHeader() throws IOException { 649 bout.writeShort(STREAM_MAGIC); 650 bout.writeShort(STREAM_VERSION); 651 } 652 653 /** 654 * Write the specified class descriptor to the ObjectOutputStream. Class 655 * descriptors are used to identify the classes of objects written to the 656 * stream. Subclasses of ObjectOutputStream may override this method to 657 * customize the way in which class descriptors are written to the 658 * serialization stream. The corresponding method in ObjectInputStream, 659 * {@link ObjectInputStream#readClassDescriptor readClassDescriptor}, should then be overridden to 660 * reconstitute the class descriptor from its custom stream representation. 661 * By default, this method writes class descriptors according to the format 662 * defined in the <a href="{@docRoot}/../specs/serialization/index.html"> 663 * <cite>Java Object Serialization Specification</cite></a>. 664 * 665 * <p>Note that this method will only be called if the ObjectOutputStream 666 * is not using the old serialization stream format (set by calling 667 * ObjectOutputStream's {@code useProtocolVersion} method). If this 668 * serialization stream is using the old format 669 * ({@code PROTOCOL_VERSION_1}), the class descriptor will be written 670 * internally in a manner that cannot be overridden or customized. 671 * 672 * @param desc class descriptor to write to the stream 673 * @throws IOException If an I/O error has occurred. 674 * @see java.io.ObjectInputStream#readClassDescriptor() 675 * @see #useProtocolVersion(int) 676 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_1 677 * @since 1.3 678 */ 679 protected void writeClassDescriptor(ObjectStreamClass desc) 680 throws IOException 681 { 682 desc.writeNonProxy(this); 683 } 684 685 /** 686 * Writes a byte. This method will block until the byte is actually 687 * written. 688 * 689 * @param val the byte to be written to the stream 690 * @throws IOException If an I/O error has occurred. 691 */ 692 public void write(int val) throws IOException { 693 bout.write(val); 694 } 695 696 /** 697 * Writes an array of bytes. This method will block until the bytes are 698 * actually written. 699 * 700 * @param buf the data to be written 701 * @throws IOException If an I/O error has occurred. 702 */ 703 public void write(byte[] buf) throws IOException { 704 bout.write(buf, 0, buf.length, false); 705 } 706 707 /** 708 * Writes a sub array of bytes. 709 * 710 * @param buf the data to be written 711 * @param off the start offset in the data 712 * @param len the number of bytes that are written 713 * @throws IOException If an I/O error has occurred. 714 */ 715 public void write(byte[] buf, int off, int len) throws IOException { 716 if (buf == null) { 717 throw new NullPointerException(); 718 } 719 Objects.checkFromIndexSize(off, len, buf.length); 720 bout.write(buf, off, len, false); 721 } 722 723 /** 724 * Flushes the stream. This will write any buffered output bytes and flush 725 * through to the underlying stream. 726 * 727 * @throws IOException If an I/O error has occurred. 728 */ 729 public void flush() throws IOException { 730 bout.flush(); 731 } 732 733 /** 734 * Drain any buffered data in ObjectOutputStream. Similar to flush but 735 * does not propagate the flush to the underlying stream. 736 * 737 * @throws IOException if I/O errors occur while writing to the underlying 738 * stream 739 */ 740 protected void drain() throws IOException { 741 bout.drain(); 742 } 743 744 /** 745 * Closes the stream. This method must be called to release any resources 746 * associated with the stream. 747 * 748 * @throws IOException If an I/O error has occurred. 749 */ 750 public void close() throws IOException { 751 flush(); 752 clear(); 753 bout.close(); 754 } 755 756 /** 757 * Writes a boolean. 758 * 759 * @param val the boolean to be written 760 * @throws IOException if I/O errors occur while writing to the underlying 761 * stream 762 */ 763 public void writeBoolean(boolean val) throws IOException { 764 bout.writeBoolean(val); 765 } 766 767 /** 768 * Writes an 8 bit byte. 769 * 770 * @param val the byte value to be written 771 * @throws IOException if I/O errors occur while writing to the underlying 772 * stream 773 */ 774 public void writeByte(int val) throws IOException { 775 bout.writeByte(val); 776 } 777 778 /** 779 * Writes a 16 bit short. 780 * 781 * @param val the short value to be written 782 * @throws IOException if I/O errors occur while writing to the underlying 783 * stream 784 */ 785 public void writeShort(int val) throws IOException { 786 bout.writeShort(val); 787 } 788 789 /** 790 * Writes a 16 bit char. 791 * 792 * @param val the char value to be written 793 * @throws IOException if I/O errors occur while writing to the underlying 794 * stream 795 */ 796 public void writeChar(int val) throws IOException { 797 bout.writeChar(val); 798 } 799 800 /** 801 * Writes a 32 bit int. 802 * 803 * @param val the integer value to be written 804 * @throws IOException if I/O errors occur while writing to the underlying 805 * stream 806 */ 807 public void writeInt(int val) throws IOException { 808 bout.writeInt(val); 809 } 810 811 /** 812 * Writes a 64 bit long. 813 * 814 * @param val the long value to be written 815 * @throws IOException if I/O errors occur while writing to the underlying 816 * stream 817 */ 818 public void writeLong(long val) throws IOException { 819 bout.writeLong(val); 820 } 821 822 /** 823 * Writes a 32 bit float. 824 * 825 * @param val the float value to be written 826 * @throws IOException if I/O errors occur while writing to the underlying 827 * stream 828 */ 829 public void writeFloat(float val) throws IOException { 830 bout.writeFloat(val); 831 } 832 833 /** 834 * Writes a 64 bit double. 835 * 836 * @param val the double value to be written 837 * @throws IOException if I/O errors occur while writing to the underlying 838 * stream 839 */ 840 public void writeDouble(double val) throws IOException { 841 bout.writeDouble(val); 842 } 843 844 /** 845 * Writes a String as a sequence of bytes. 846 * 847 * @param str the String of bytes to be written 848 * @throws IOException if I/O errors occur while writing to the underlying 849 * stream 850 */ 851 public void writeBytes(String str) throws IOException { 852 bout.writeBytes(str); 853 } 854 855 /** 856 * Writes a String as a sequence of chars. 857 * 858 * @param str the String of chars to be written 859 * @throws IOException if I/O errors occur while writing to the underlying 860 * stream 861 */ 862 public void writeChars(String str) throws IOException { 863 bout.writeChars(str); 864 } 865 866 /** 867 * Primitive data write of this String in 868 * <a href="DataInput.html#modified-utf-8">modified UTF-8</a> 869 * format. Note that there is a 870 * significant difference between writing a String into the stream as 871 * primitive data or as an Object. A String instance written by writeObject 872 * is written into the stream as a String initially. Future writeObject() 873 * calls write references to the string into the stream. 874 * 875 * @param str the String to be written 876 * @throws IOException if I/O errors occur while writing to the underlying 877 * stream 878 */ 879 public void writeUTF(String str) throws IOException { 880 bout.writeUTF(str); 881 } 882 883 /** 884 * Provide programmatic access to the persistent fields to be written 885 * to ObjectOutput. 886 * 887 * @since 1.2 888 */ 889 public abstract static class PutField { 890 /** 891 * Constructor for subclasses to call. 892 */ 893 public PutField() {} 894 895 /** 896 * Put the value of the named boolean field into the persistent field. 897 * 898 * @param name the name of the serializable field 899 * @param val the value to assign to the field 900 * @throws IllegalArgumentException if {@code name} does not 901 * match the name of a serializable field for the class whose fields 902 * are being written, or if the type of the named field is not 903 * {@code boolean} 904 */ 905 public abstract void put(String name, boolean val); 906 907 /** 908 * Put the value of the named byte field into the persistent field. 909 * 910 * @param name the name of the serializable field 911 * @param val the value to assign to the field 912 * @throws IllegalArgumentException if {@code name} does not 913 * match the name of a serializable field for the class whose fields 914 * are being written, or if the type of the named field is not 915 * {@code byte} 916 */ 917 public abstract void put(String name, byte val); 918 919 /** 920 * Put the value of the named char field into the persistent field. 921 * 922 * @param name the name of the serializable field 923 * @param val the value to assign to the field 924 * @throws IllegalArgumentException if {@code name} does not 925 * match the name of a serializable field for the class whose fields 926 * are being written, or if the type of the named field is not 927 * {@code char} 928 */ 929 public abstract void put(String name, char val); 930 931 /** 932 * Put the value of the named short field into the persistent field. 933 * 934 * @param name the name of the serializable field 935 * @param val the value to assign to the field 936 * @throws IllegalArgumentException if {@code name} does not 937 * match the name of a serializable field for the class whose fields 938 * are being written, or if the type of the named field is not 939 * {@code short} 940 */ 941 public abstract void put(String name, short val); 942 943 /** 944 * Put the value of the named int field into the persistent field. 945 * 946 * @param name the name of the serializable field 947 * @param val the value to assign to the field 948 * @throws IllegalArgumentException if {@code name} does not 949 * match the name of a serializable field for the class whose fields 950 * are being written, or if the type of the named field is not 951 * {@code int} 952 */ 953 public abstract void put(String name, int val); 954 955 /** 956 * Put the value of the named long field into the persistent field. 957 * 958 * @param name the name of the serializable field 959 * @param val the value to assign to the field 960 * @throws IllegalArgumentException if {@code name} does not 961 * match the name of a serializable field for the class whose fields 962 * are being written, or if the type of the named field is not 963 * {@code long} 964 */ 965 public abstract void put(String name, long val); 966 967 /** 968 * Put the value of the named float field into the persistent field. 969 * 970 * @param name the name of the serializable field 971 * @param val the value to assign to the field 972 * @throws IllegalArgumentException if {@code name} does not 973 * match the name of a serializable field for the class whose fields 974 * are being written, or if the type of the named field is not 975 * {@code float} 976 */ 977 public abstract void put(String name, float val); 978 979 /** 980 * Put the value of the named double field into the persistent field. 981 * 982 * @param name the name of the serializable field 983 * @param val the value to assign to the field 984 * @throws IllegalArgumentException if {@code name} does not 985 * match the name of a serializable field for the class whose fields 986 * are being written, or if the type of the named field is not 987 * {@code double} 988 */ 989 public abstract void put(String name, double val); 990 991 /** 992 * Put the value of the named Object field into the persistent field. 993 * 994 * @param name the name of the serializable field 995 * @param val the value to assign to the field 996 * (which may be {@code null}) 997 * @throws IllegalArgumentException if {@code name} does not 998 * match the name of a serializable field for the class whose fields 999 * are being written, or if the type of the named field is not a 1000 * reference type 1001 */ 1002 public abstract void put(String name, Object val); 1003 1004 /** 1005 * Write the data and fields to the specified ObjectOutput stream, 1006 * which must be the same stream that produced this 1007 * {@code PutField} object. 1008 * 1009 * @param out the stream to write the data and fields to 1010 * @throws IOException if I/O errors occur while writing to the 1011 * underlying stream 1012 * @throws IllegalArgumentException if the specified stream is not 1013 * the same stream that produced this {@code PutField} 1014 * object 1015 * @deprecated This method does not write the values contained by this 1016 * {@code PutField} object in a proper format, and may 1017 * result in corruption of the serialization stream. The 1018 * correct way to write {@code PutField} data is by 1019 * calling the {@link java.io.ObjectOutputStream#writeFields()} 1020 * method. 1021 */ 1022 @Deprecated 1023 public abstract void write(ObjectOutput out) throws IOException; 1024 } 1025 1026 1027 /** 1028 * Returns protocol version in use. 1029 */ 1030 int getProtocolVersion() { 1031 return protocol; 1032 } 1033 1034 /** 1035 * Writes string without allowing it to be replaced in stream. Used by 1036 * ObjectStreamClass to write class descriptor type strings. 1037 */ 1038 void writeTypeString(String str) throws IOException { 1039 int handle; 1040 if (str == null) { 1041 writeNull(); 1042 } else if ((handle = handles.lookup(str)) != -1) { 1043 writeHandle(handle); 1044 } else { 1045 writeString(str, false); 1046 } 1047 } 1048 1049 /** 1050 * Verifies that this (possibly subclass) instance can be constructed 1051 * without violating security constraints: the subclass must not override 1052 * security-sensitive non-final methods, or else the 1053 * "enableSubclassImplementation" SerializablePermission is checked. 1054 */ 1055 private void verifySubclass() { 1056 Class<?> cl = getClass(); 1057 if (cl == ObjectOutputStream.class) { 1058 return; 1059 } 1060 @SuppressWarnings("removal") 1061 SecurityManager sm = System.getSecurityManager(); 1062 if (sm == null) { 1063 return; 1064 } 1065 boolean result = Caches.subclassAudits.get(cl); 1066 if (!result) { 1067 sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION); 1068 } 1069 } 1070 1071 /** 1072 * Performs reflective checks on given subclass to verify that it doesn't 1073 * override security-sensitive non-final methods. Returns TRUE if subclass 1074 * is "safe", FALSE otherwise. 1075 */ 1076 @SuppressWarnings("removal") 1077 private static Boolean auditSubclass(Class<?> subcl) { 1078 return AccessController.doPrivileged( 1079 new PrivilegedAction<>() { 1080 public Boolean run() { 1081 for (Class<?> cl = subcl; 1082 cl != ObjectOutputStream.class; 1083 cl = cl.getSuperclass()) 1084 { 1085 try { 1086 cl.getDeclaredMethod( 1087 "writeUnshared", new Class<?>[] { Object.class }); 1088 return Boolean.FALSE; 1089 } catch (NoSuchMethodException ex) { 1090 } 1091 try { 1092 cl.getDeclaredMethod("putFields", (Class<?>[]) null); 1093 return Boolean.FALSE; 1094 } catch (NoSuchMethodException ex) { 1095 } 1096 } 1097 return Boolean.TRUE; 1098 } 1099 } 1100 ); 1101 } 1102 1103 /** 1104 * Clears internal data structures. 1105 */ 1106 private void clear() { 1107 subs.clear(); 1108 handles.clear(); 1109 } 1110 1111 /** 1112 * Underlying writeObject/writeUnshared implementation. 1113 */ 1114 private void writeObject0(Object obj, boolean unshared) 1115 throws IOException 1116 { 1117 boolean oldMode = bout.setBlockDataMode(false); 1118 depth++; 1119 try { 1120 // handle previously written and non-replaceable objects 1121 int h; 1122 if ((obj = subs.lookup(obj)) == null) { 1123 writeNull(); 1124 return; 1125 } else if (!unshared && (h = handles.lookup(obj)) != -1) { 1126 writeHandle(h); 1127 return; 1128 } else if (obj instanceof Class) { 1129 writeClass((Class) obj, unshared); 1130 return; 1131 } else if (obj instanceof ObjectStreamClass) { 1132 writeClassDesc((ObjectStreamClass) obj, unshared); 1133 return; 1134 } 1135 1136 // check for replacement object 1137 Object orig = obj; 1138 Class<?> cl = obj.getClass(); 1139 ObjectStreamClass desc; 1140 for (;;) { 1141 // REMIND: skip this check for strings/arrays? 1142 Class<?> repCl; 1143 desc = ObjectStreamClass.lookup(cl, true); 1144 if (!desc.hasWriteReplaceMethod() || 1145 (obj = desc.invokeWriteReplace(obj)) == null || 1146 (repCl = obj.getClass()) == cl) 1147 { 1148 break; 1149 } 1150 cl = repCl; 1151 } 1152 if (enableReplace) { 1153 Object rep = replaceObject(obj); 1154 if (rep != obj && rep != null) { 1155 cl = rep.getClass(); 1156 desc = ObjectStreamClass.lookup(cl, true); 1157 } 1158 obj = rep; 1159 } 1160 1161 // if object replaced, run through original checks a second time 1162 if (obj != orig) { 1163 subs.assign(orig, obj); 1164 if (obj == null) { 1165 writeNull(); 1166 return; 1167 } else if (!unshared && (h = handles.lookup(obj)) != -1) { 1168 writeHandle(h); 1169 return; 1170 } else if (obj instanceof Class) { 1171 writeClass((Class) obj, unshared); 1172 return; 1173 } else if (obj instanceof ObjectStreamClass) { 1174 writeClassDesc((ObjectStreamClass) obj, unshared); 1175 return; 1176 } 1177 } 1178 1179 // remaining cases 1180 if (obj instanceof String) { 1181 writeString((String) obj, unshared); 1182 } else if (cl.isArray()) { 1183 writeArray(obj, desc, unshared); 1184 } else if (obj instanceof Enum) { 1185 writeEnum((Enum<?>) obj, desc, unshared); 1186 } else if (obj instanceof Serializable) { 1187 writeOrdinaryObject(obj, desc, unshared); 1188 } else { 1189 if (extendedDebugInfo) { 1190 throw new NotSerializableException( 1191 cl.getName() + "\n" + debugInfoStack.toString()); 1192 } else { 1193 throw new NotSerializableException(cl.getName()); 1194 } 1195 } 1196 } finally { 1197 depth--; 1198 bout.setBlockDataMode(oldMode); 1199 } 1200 } 1201 1202 /** 1203 * Writes null code to stream. 1204 */ 1205 private void writeNull() throws IOException { 1206 bout.writeByte(TC_NULL); 1207 } 1208 1209 /** 1210 * Writes given object handle to stream. 1211 */ 1212 private void writeHandle(int handle) throws IOException { 1213 bout.writeByte(TC_REFERENCE); 1214 bout.writeInt(baseWireHandle + handle); 1215 } 1216 1217 /** 1218 * Writes representation of given class to stream. 1219 */ 1220 private void writeClass(Class<?> cl, boolean unshared) throws IOException { 1221 bout.writeByte(TC_CLASS); 1222 writeClassDesc(ObjectStreamClass.lookup(cl, true), false); 1223 handles.assign(unshared ? null : cl); 1224 } 1225 1226 /** 1227 * Writes representation of given class descriptor to stream. 1228 */ 1229 private void writeClassDesc(ObjectStreamClass desc, boolean unshared) 1230 throws IOException 1231 { 1232 int handle; 1233 if (desc == null) { 1234 writeNull(); 1235 } else if (!unshared && (handle = handles.lookup(desc)) != -1) { 1236 writeHandle(handle); 1237 } else if (desc.isProxy()) { 1238 writeProxyDesc(desc, unshared); 1239 } else { 1240 writeNonProxyDesc(desc, unshared); 1241 } 1242 } 1243 1244 private boolean isCustomSubclass() { 1245 // Return true if this class is a custom subclass of ObjectOutputStream 1246 return getClass().getClassLoader() 1247 != ObjectOutputStream.class.getClassLoader(); 1248 } 1249 1250 /** 1251 * Writes class descriptor representing a dynamic proxy class to stream. 1252 */ 1253 private void writeProxyDesc(ObjectStreamClass desc, boolean unshared) 1254 throws IOException 1255 { 1256 bout.writeByte(TC_PROXYCLASSDESC); 1257 handles.assign(unshared ? null : desc); 1258 1259 Class<?> cl = desc.forClass(); 1260 Class<?>[] ifaces = cl.getInterfaces(); 1261 bout.writeInt(ifaces.length); 1262 for (int i = 0; i < ifaces.length; i++) { 1263 bout.writeUTF(ifaces[i].getName()); 1264 } 1265 1266 bout.setBlockDataMode(true); 1267 if (cl != null && isCustomSubclass()) { 1268 ReflectUtil.checkPackageAccess(cl); 1269 } 1270 annotateProxyClass(cl); 1271 bout.setBlockDataMode(false); 1272 bout.writeByte(TC_ENDBLOCKDATA); 1273 1274 writeClassDesc(desc.getSuperDesc(), false); 1275 } 1276 1277 /** 1278 * Writes class descriptor representing a standard (i.e., not a dynamic 1279 * proxy) class to stream. 1280 */ 1281 private void writeNonProxyDesc(ObjectStreamClass desc, boolean unshared) 1282 throws IOException 1283 { 1284 bout.writeByte(TC_CLASSDESC); 1285 handles.assign(unshared ? null : desc); 1286 1287 if (protocol == PROTOCOL_VERSION_1) { 1288 // do not invoke class descriptor write hook with old protocol 1289 desc.writeNonProxy(this); 1290 } else { 1291 writeClassDescriptor(desc); 1292 } 1293 1294 Class<?> cl = desc.forClass(); 1295 bout.setBlockDataMode(true); 1296 if (cl != null && isCustomSubclass()) { 1297 ReflectUtil.checkPackageAccess(cl); 1298 } 1299 annotateClass(cl); 1300 bout.setBlockDataMode(false); 1301 bout.writeByte(TC_ENDBLOCKDATA); 1302 1303 writeClassDesc(desc.getSuperDesc(), false); 1304 } 1305 1306 /** 1307 * Writes given string to stream, using standard or long UTF format 1308 * depending on string length. 1309 */ 1310 private void writeString(String str, boolean unshared) throws IOException { 1311 handles.assign(unshared ? null : str); 1312 long utflen = bout.getUTFLength(str); 1313 if (utflen <= 0xFFFF) { 1314 bout.writeByte(TC_STRING); 1315 bout.writeUTF(str, utflen); 1316 } else { 1317 bout.writeByte(TC_LONGSTRING); 1318 bout.writeLongUTF(str, utflen); 1319 } 1320 } 1321 1322 /** 1323 * Writes given array object to stream. 1324 */ 1325 private void writeArray(Object array, 1326 ObjectStreamClass desc, 1327 boolean unshared) 1328 throws IOException 1329 { 1330 bout.writeByte(TC_ARRAY); 1331 writeClassDesc(desc, false); 1332 handles.assign(unshared ? null : array); 1333 1334 Class<?> ccl = desc.forClass().getComponentType(); 1335 if (ccl.isPrimitive()) { 1336 if (ccl == Integer.TYPE) { 1337 int[] ia = (int[]) array; 1338 bout.writeInt(ia.length); 1339 bout.writeInts(ia, 0, ia.length); 1340 } else if (ccl == Byte.TYPE) { 1341 byte[] ba = (byte[]) array; 1342 bout.writeInt(ba.length); 1343 bout.write(ba, 0, ba.length, true); 1344 } else if (ccl == Long.TYPE) { 1345 long[] ja = (long[]) array; 1346 bout.writeInt(ja.length); 1347 bout.writeLongs(ja, 0, ja.length); 1348 } else if (ccl == Float.TYPE) { 1349 float[] fa = (float[]) array; 1350 bout.writeInt(fa.length); 1351 bout.writeFloats(fa, 0, fa.length); 1352 } else if (ccl == Double.TYPE) { 1353 double[] da = (double[]) array; 1354 bout.writeInt(da.length); 1355 bout.writeDoubles(da, 0, da.length); 1356 } else if (ccl == Short.TYPE) { 1357 short[] sa = (short[]) array; 1358 bout.writeInt(sa.length); 1359 bout.writeShorts(sa, 0, sa.length); 1360 } else if (ccl == Character.TYPE) { 1361 char[] ca = (char[]) array; 1362 bout.writeInt(ca.length); 1363 bout.writeChars(ca, 0, ca.length); 1364 } else if (ccl == Boolean.TYPE) { 1365 boolean[] za = (boolean[]) array; 1366 bout.writeInt(za.length); 1367 bout.writeBooleans(za, 0, za.length); 1368 } else { 1369 throw new InternalError(); 1370 } 1371 } else { 1372 Object[] objs = (Object[]) array; 1373 int len = objs.length; 1374 bout.writeInt(len); 1375 if (extendedDebugInfo) { 1376 debugInfoStack.push( 1377 "array (class \"" + array.getClass().getName() + 1378 "\", size: " + len + ")"); 1379 } 1380 try { 1381 for (int i = 0; i < len; i++) { 1382 if (extendedDebugInfo) { 1383 debugInfoStack.push( 1384 "element of array (index: " + i + ")"); 1385 } 1386 try { 1387 writeObject0(objs[i], false); 1388 } finally { 1389 if (extendedDebugInfo) { 1390 debugInfoStack.pop(); 1391 } 1392 } 1393 } 1394 } finally { 1395 if (extendedDebugInfo) { 1396 debugInfoStack.pop(); 1397 } 1398 } 1399 } 1400 } 1401 1402 /** 1403 * Writes given enum constant to stream. 1404 */ 1405 private void writeEnum(Enum<?> en, 1406 ObjectStreamClass desc, 1407 boolean unshared) 1408 throws IOException 1409 { 1410 bout.writeByte(TC_ENUM); 1411 ObjectStreamClass sdesc = desc.getSuperDesc(); 1412 writeClassDesc((sdesc.forClass() == Enum.class) ? desc : sdesc, false); 1413 handles.assign(unshared ? null : en); 1414 writeString(en.name(), false); 1415 } 1416 1417 /** 1418 * Writes representation of an "ordinary" (i.e., not a String, Class, 1419 * ObjectStreamClass, array, or enum constant) serializable object to the 1420 * stream. 1421 */ 1422 private void writeOrdinaryObject(Object obj, 1423 ObjectStreamClass desc, 1424 boolean unshared) 1425 throws IOException 1426 { 1427 if (extendedDebugInfo) { 1428 debugInfoStack.push( 1429 (depth == 1 ? "root " : "") + "object (class \"" + 1430 obj.getClass().getName() + "\", " + obj.toString() + ")"); 1431 } 1432 try { 1433 desc.checkSerialize(); 1434 1435 bout.writeByte(TC_OBJECT); 1436 writeClassDesc(desc, false); 1437 handles.assign(unshared ? null : obj); 1438 1439 if (desc.isRecord()) { 1440 writeRecordData(obj, desc); 1441 } else if (desc.isExternalizable() && !desc.isProxy()) { 1442 writeExternalData((Externalizable) obj); 1443 } else { 1444 writeSerialData(obj, desc); 1445 } 1446 } finally { 1447 if (extendedDebugInfo) { 1448 debugInfoStack.pop(); 1449 } 1450 } 1451 } 1452 1453 /** 1454 * Writes externalizable data of given object by invoking its 1455 * writeExternal() method. 1456 */ 1457 private void writeExternalData(Externalizable obj) throws IOException { 1458 PutFieldImpl oldPut = curPut; 1459 curPut = null; 1460 1461 if (extendedDebugInfo) { 1462 debugInfoStack.push("writeExternal data"); 1463 } 1464 SerialCallbackContext oldContext = curContext; 1465 try { 1466 curContext = null; 1467 if (protocol == PROTOCOL_VERSION_1) { 1468 obj.writeExternal(this); 1469 } else { 1470 bout.setBlockDataMode(true); 1471 obj.writeExternal(this); 1472 bout.setBlockDataMode(false); 1473 bout.writeByte(TC_ENDBLOCKDATA); 1474 } 1475 } finally { 1476 curContext = oldContext; 1477 if (extendedDebugInfo) { 1478 debugInfoStack.pop(); 1479 } 1480 } 1481 1482 curPut = oldPut; 1483 } 1484 1485 /** Writes the record component values for the given record object. */ 1486 private void writeRecordData(Object obj, ObjectStreamClass desc) 1487 throws IOException 1488 { 1489 assert obj.getClass().isRecord(); 1490 ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout(); 1491 if (slots.length != 1) { 1492 throw new InvalidClassException( 1493 "expected a single record slot length, but found: " + slots.length); 1494 } 1495 1496 defaultWriteFields(obj, desc); // #### seems unnecessary to use the accessors 1497 } 1498 1499 /** 1500 * Writes instance data for each serializable class of given object, from 1501 * superclass to subclass. 1502 */ 1503 private void writeSerialData(Object obj, ObjectStreamClass desc) 1504 throws IOException 1505 { 1506 ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout(); 1507 for (int i = 0; i < slots.length; i++) { 1508 ObjectStreamClass slotDesc = slots[i].desc; 1509 if (slotDesc.hasWriteObjectMethod()) { 1510 PutFieldImpl oldPut = curPut; 1511 curPut = null; 1512 SerialCallbackContext oldContext = curContext; 1513 1514 if (extendedDebugInfo) { 1515 debugInfoStack.push( 1516 "custom writeObject data (class \"" + 1517 slotDesc.getName() + "\")"); 1518 } 1519 try { 1520 curContext = new SerialCallbackContext(obj, slotDesc); 1521 bout.setBlockDataMode(true); 1522 slotDesc.invokeWriteObject(obj, this); 1523 bout.setBlockDataMode(false); 1524 bout.writeByte(TC_ENDBLOCKDATA); 1525 } finally { 1526 curContext.setUsed(); 1527 curContext = oldContext; 1528 if (extendedDebugInfo) { 1529 debugInfoStack.pop(); 1530 } 1531 } 1532 1533 curPut = oldPut; 1534 } else { 1535 defaultWriteFields(obj, slotDesc); 1536 } 1537 } 1538 } 1539 1540 /** 1541 * Fetches and writes values of serializable fields of given object to 1542 * stream. The given class descriptor specifies which field values to 1543 * write, and in which order they should be written. 1544 */ 1545 private void defaultWriteFields(Object obj, ObjectStreamClass desc) 1546 throws IOException 1547 { 1548 Class<?> cl = desc.forClass(); 1549 if (cl != null && obj != null && !cl.isInstance(obj)) { 1550 throw new ClassCastException(); 1551 } 1552 1553 desc.checkDefaultSerialize(); 1554 1555 int primDataSize = desc.getPrimDataSize(); 1556 if (primDataSize > 0) { 1557 if (primVals == null || primVals.length < primDataSize) { 1558 primVals = new byte[primDataSize]; 1559 } 1560 desc.getPrimFieldValues(obj, primVals); 1561 bout.write(primVals, 0, primDataSize, false); 1562 } 1563 1564 int numObjFields = desc.getNumObjFields(); 1565 if (numObjFields > 0) { 1566 ObjectStreamField[] fields = desc.getFields(false); 1567 Object[] objVals = new Object[numObjFields]; 1568 int numPrimFields = fields.length - objVals.length; 1569 desc.getObjFieldValues(obj, objVals); 1570 for (int i = 0; i < objVals.length; i++) { 1571 if (extendedDebugInfo) { 1572 debugInfoStack.push( 1573 "field (class \"" + desc.getName() + "\", name: \"" + 1574 fields[numPrimFields + i].getName() + "\", type: \"" + 1575 fields[numPrimFields + i].getType() + "\")"); 1576 } 1577 try { 1578 writeObject0(objVals[i], 1579 fields[numPrimFields + i].isUnshared()); 1580 } finally { 1581 if (extendedDebugInfo) { 1582 debugInfoStack.pop(); 1583 } 1584 } 1585 } 1586 } 1587 } 1588 1589 /** 1590 * Attempts to write to stream fatal IOException that has caused 1591 * serialization to abort. 1592 */ 1593 private void writeFatalException(IOException ex) throws IOException { 1594 /* 1595 * Note: the serialization specification states that if a second 1596 * IOException occurs while attempting to serialize the original fatal 1597 * exception to the stream, then a StreamCorruptedException should be 1598 * thrown (section 2.1). However, due to a bug in previous 1599 * implementations of serialization, StreamCorruptedExceptions were 1600 * rarely (if ever) actually thrown--the "root" exceptions from 1601 * underlying streams were thrown instead. This historical behavior is 1602 * followed here for consistency. 1603 */ 1604 clear(); 1605 boolean oldMode = bout.setBlockDataMode(false); 1606 try { 1607 bout.writeByte(TC_EXCEPTION); 1608 writeObject0(ex, false); 1609 clear(); 1610 } finally { 1611 bout.setBlockDataMode(oldMode); 1612 } 1613 } 1614 1615 /** 1616 * Default PutField implementation. 1617 */ 1618 private class PutFieldImpl extends PutField { 1619 1620 /** class descriptor describing serializable fields */ 1621 private final ObjectStreamClass desc; 1622 /** primitive field values */ 1623 private final byte[] primVals; 1624 /** object field values */ 1625 private final Object[] objVals; 1626 1627 /** 1628 * Creates PutFieldImpl object for writing fields defined in given 1629 * class descriptor. 1630 */ 1631 PutFieldImpl(ObjectStreamClass desc) { 1632 this.desc = desc; 1633 primVals = new byte[desc.getPrimDataSize()]; 1634 objVals = new Object[desc.getNumObjFields()]; 1635 } 1636 1637 public void put(String name, boolean val) { 1638 Bits.putBoolean(primVals, getFieldOffset(name, Boolean.TYPE), val); 1639 } 1640 1641 public void put(String name, byte val) { 1642 primVals[getFieldOffset(name, Byte.TYPE)] = val; 1643 } 1644 1645 public void put(String name, char val) { 1646 Bits.putChar(primVals, getFieldOffset(name, Character.TYPE), val); 1647 } 1648 1649 public void put(String name, short val) { 1650 Bits.putShort(primVals, getFieldOffset(name, Short.TYPE), val); 1651 } 1652 1653 public void put(String name, int val) { 1654 Bits.putInt(primVals, getFieldOffset(name, Integer.TYPE), val); 1655 } 1656 1657 public void put(String name, float val) { 1658 Bits.putFloat(primVals, getFieldOffset(name, Float.TYPE), val); 1659 } 1660 1661 public void put(String name, long val) { 1662 Bits.putLong(primVals, getFieldOffset(name, Long.TYPE), val); 1663 } 1664 1665 public void put(String name, double val) { 1666 Bits.putDouble(primVals, getFieldOffset(name, Double.TYPE), val); 1667 } 1668 1669 public void put(String name, Object val) { 1670 objVals[getFieldOffset(name, Object.class)] = val; 1671 } 1672 1673 // deprecated in ObjectOutputStream.PutField 1674 public void write(ObjectOutput out) throws IOException { 1675 /* 1676 * Applications should *not* use this method to write PutField 1677 * data, as it will lead to stream corruption if the PutField 1678 * object writes any primitive data (since block data mode is not 1679 * unset/set properly, as is done in OOS.writeFields()). This 1680 * broken implementation is being retained solely for behavioral 1681 * compatibility, in order to support applications which use 1682 * OOS.PutField.write() for writing only non-primitive data. 1683 * 1684 * Serialization of unshared objects is not implemented here since 1685 * it is not necessary for backwards compatibility; also, unshared 1686 * semantics may not be supported by the given ObjectOutput 1687 * instance. Applications which write unshared objects using the 1688 * PutField API must use OOS.writeFields(). 1689 */ 1690 if (ObjectOutputStream.this != out) { 1691 throw new IllegalArgumentException("wrong stream"); 1692 } 1693 out.write(primVals, 0, primVals.length); 1694 1695 ObjectStreamField[] fields = desc.getFields(false); 1696 int numPrimFields = fields.length - objVals.length; 1697 // REMIND: warn if numPrimFields > 0? 1698 for (int i = 0; i < objVals.length; i++) { 1699 if (fields[numPrimFields + i].isUnshared()) { 1700 throw new IOException("cannot write unshared object"); 1701 } 1702 out.writeObject(objVals[i]); 1703 } 1704 } 1705 1706 /** 1707 * Writes buffered primitive data and object fields to stream. 1708 */ 1709 void writeFields() throws IOException { 1710 bout.write(primVals, 0, primVals.length, false); 1711 1712 ObjectStreamField[] fields = desc.getFields(false); 1713 int numPrimFields = fields.length - objVals.length; 1714 for (int i = 0; i < objVals.length; i++) { 1715 if (extendedDebugInfo) { 1716 debugInfoStack.push( 1717 "field (class \"" + desc.getName() + "\", name: \"" + 1718 fields[numPrimFields + i].getName() + "\", type: \"" + 1719 fields[numPrimFields + i].getType() + "\")"); 1720 } 1721 try { 1722 writeObject0(objVals[i], 1723 fields[numPrimFields + i].isUnshared()); 1724 } finally { 1725 if (extendedDebugInfo) { 1726 debugInfoStack.pop(); 1727 } 1728 } 1729 } 1730 } 1731 1732 /** 1733 * Returns offset of field with given name and type. A specified type 1734 * of null matches all types, Object.class matches all non-primitive 1735 * types, and any other non-null type matches assignable types only. 1736 * Throws IllegalArgumentException if no matching field found. 1737 */ 1738 private int getFieldOffset(String name, Class<?> type) { 1739 ObjectStreamField field = desc.getField(name, type); 1740 if (field == null) { 1741 throw new IllegalArgumentException("no such field " + name + 1742 " with type " + type); 1743 } 1744 return field.getOffset(); 1745 } 1746 } 1747 1748 /** 1749 * Buffered output stream with two modes: in default mode, outputs data in 1750 * same format as DataOutputStream; in "block data" mode, outputs data 1751 * bracketed by block data markers (see object serialization specification 1752 * for details). 1753 */ 1754 private static class BlockDataOutputStream 1755 extends OutputStream implements DataOutput 1756 { 1757 /** maximum data block length */ 1758 private static final int MAX_BLOCK_SIZE = 1024; 1759 /** maximum data block header length */ 1760 private static final int MAX_HEADER_SIZE = 5; 1761 /** (tunable) length of char buffer (for writing strings) */ 1762 private static final int CHAR_BUF_SIZE = 256; 1763 1764 /** buffer for writing general/block data */ 1765 private final byte[] buf = new byte[MAX_BLOCK_SIZE]; 1766 /** buffer for writing block data headers */ 1767 private final byte[] hbuf = new byte[MAX_HEADER_SIZE]; 1768 /** char buffer for fast string writes */ 1769 private final char[] cbuf = new char[CHAR_BUF_SIZE]; 1770 1771 /** block data mode */ 1772 private boolean blkmode = false; 1773 /** current offset into buf */ 1774 private int pos = 0; 1775 1776 /** underlying output stream */ 1777 private final OutputStream out; 1778 /** loopback stream (for data writes that span data blocks) */ 1779 private final DataOutputStream dout; 1780 1781 /** 1782 * Creates new BlockDataOutputStream on top of given underlying stream. 1783 * Block data mode is turned off by default. 1784 */ 1785 BlockDataOutputStream(OutputStream out) { 1786 this.out = out; 1787 dout = new DataOutputStream(this); 1788 } 1789 1790 /** 1791 * Sets block data mode to the given mode (true == on, false == off) 1792 * and returns the previous mode value. If the new mode is the same as 1793 * the old mode, no action is taken. If the new mode differs from the 1794 * old mode, any buffered data is flushed before switching to the new 1795 * mode. 1796 */ 1797 boolean setBlockDataMode(boolean mode) throws IOException { 1798 if (blkmode == mode) { 1799 return blkmode; 1800 } 1801 drain(); 1802 blkmode = mode; 1803 return !blkmode; 1804 } 1805 1806 /** 1807 * Returns true if the stream is currently in block data mode, false 1808 * otherwise. 1809 */ 1810 boolean getBlockDataMode() { 1811 return blkmode; 1812 } 1813 1814 /* ----------------- generic output stream methods ----------------- */ 1815 /* 1816 * The following methods are equivalent to their counterparts in 1817 * OutputStream, except that they partition written data into data 1818 * blocks when in block data mode. 1819 */ 1820 1821 public void write(int b) throws IOException { 1822 if (pos >= MAX_BLOCK_SIZE) { 1823 drain(); 1824 } 1825 buf[pos++] = (byte) b; 1826 } 1827 1828 public void write(byte[] b) throws IOException { 1829 write(b, 0, b.length, false); 1830 } 1831 1832 public void write(byte[] b, int off, int len) throws IOException { 1833 write(b, off, len, false); 1834 } 1835 1836 public void flush() throws IOException { 1837 drain(); 1838 out.flush(); 1839 } 1840 1841 public void close() throws IOException { 1842 flush(); 1843 out.close(); 1844 } 1845 1846 /** 1847 * Writes specified span of byte values from given array. If copy is 1848 * true, copies the values to an intermediate buffer before writing 1849 * them to underlying stream (to avoid exposing a reference to the 1850 * original byte array). 1851 */ 1852 void write(byte[] b, int off, int len, boolean copy) 1853 throws IOException 1854 { 1855 if (!(copy || blkmode)) { // write directly 1856 drain(); 1857 out.write(b, off, len); 1858 return; 1859 } 1860 1861 while (len > 0) { 1862 if (pos >= MAX_BLOCK_SIZE) { 1863 drain(); 1864 } 1865 if (len >= MAX_BLOCK_SIZE && !copy && pos == 0) { 1866 // avoid unnecessary copy 1867 writeBlockHeader(MAX_BLOCK_SIZE); 1868 out.write(b, off, MAX_BLOCK_SIZE); 1869 off += MAX_BLOCK_SIZE; 1870 len -= MAX_BLOCK_SIZE; 1871 } else { 1872 int wlen = Math.min(len, MAX_BLOCK_SIZE - pos); 1873 System.arraycopy(b, off, buf, pos, wlen); 1874 pos += wlen; 1875 off += wlen; 1876 len -= wlen; 1877 } 1878 } 1879 } 1880 1881 /** 1882 * Writes all buffered data from this stream to the underlying stream, 1883 * but does not flush underlying stream. 1884 */ 1885 void drain() throws IOException { 1886 if (pos == 0) { 1887 return; 1888 } 1889 if (blkmode) { 1890 writeBlockHeader(pos); 1891 } 1892 out.write(buf, 0, pos); 1893 pos = 0; 1894 } 1895 1896 /** 1897 * Writes block data header. Data blocks shorter than 256 bytes are 1898 * prefixed with a 2-byte header; all others start with a 5-byte 1899 * header. 1900 */ 1901 private void writeBlockHeader(int len) throws IOException { 1902 if (len <= 0xFF) { 1903 hbuf[0] = TC_BLOCKDATA; 1904 hbuf[1] = (byte) len; 1905 out.write(hbuf, 0, 2); 1906 } else { 1907 hbuf[0] = TC_BLOCKDATALONG; 1908 Bits.putInt(hbuf, 1, len); 1909 out.write(hbuf, 0, 5); 1910 } 1911 } 1912 1913 1914 /* ----------------- primitive data output methods ----------------- */ 1915 /* 1916 * The following methods are equivalent to their counterparts in 1917 * DataOutputStream, except that they partition written data into data 1918 * blocks when in block data mode. 1919 */ 1920 1921 public void writeBoolean(boolean v) throws IOException { 1922 if (pos >= MAX_BLOCK_SIZE) { 1923 drain(); 1924 } 1925 Bits.putBoolean(buf, pos++, v); 1926 } 1927 1928 public void writeByte(int v) throws IOException { 1929 if (pos >= MAX_BLOCK_SIZE) { 1930 drain(); 1931 } 1932 buf[pos++] = (byte) v; 1933 } 1934 1935 public void writeChar(int v) throws IOException { 1936 if (pos + 2 <= MAX_BLOCK_SIZE) { 1937 Bits.putChar(buf, pos, (char) v); 1938 pos += 2; 1939 } else { 1940 dout.writeChar(v); 1941 } 1942 } 1943 1944 public void writeShort(int v) throws IOException { 1945 if (pos + 2 <= MAX_BLOCK_SIZE) { 1946 Bits.putShort(buf, pos, (short) v); 1947 pos += 2; 1948 } else { 1949 dout.writeShort(v); 1950 } 1951 } 1952 1953 public void writeInt(int v) throws IOException { 1954 if (pos + 4 <= MAX_BLOCK_SIZE) { 1955 Bits.putInt(buf, pos, v); 1956 pos += 4; 1957 } else { 1958 dout.writeInt(v); 1959 } 1960 } 1961 1962 public void writeFloat(float v) throws IOException { 1963 if (pos + 4 <= MAX_BLOCK_SIZE) { 1964 Bits.putFloat(buf, pos, v); 1965 pos += 4; 1966 } else { 1967 dout.writeFloat(v); 1968 } 1969 } 1970 1971 public void writeLong(long v) throws IOException { 1972 if (pos + 8 <= MAX_BLOCK_SIZE) { 1973 Bits.putLong(buf, pos, v); 1974 pos += 8; 1975 } else { 1976 dout.writeLong(v); 1977 } 1978 } 1979 1980 public void writeDouble(double v) throws IOException { 1981 if (pos + 8 <= MAX_BLOCK_SIZE) { 1982 Bits.putDouble(buf, pos, v); 1983 pos += 8; 1984 } else { 1985 dout.writeDouble(v); 1986 } 1987 } 1988 1989 public void writeBytes(String s) throws IOException { 1990 int endoff = s.length(); 1991 int cpos = 0; 1992 int csize = 0; 1993 for (int off = 0; off < endoff; ) { 1994 if (cpos >= csize) { 1995 cpos = 0; 1996 csize = Math.min(endoff - off, CHAR_BUF_SIZE); 1997 s.getChars(off, off + csize, cbuf, 0); 1998 } 1999 if (pos >= MAX_BLOCK_SIZE) { 2000 drain(); 2001 } 2002 int n = Math.min(csize - cpos, MAX_BLOCK_SIZE - pos); 2003 int stop = pos + n; 2004 while (pos < stop) { 2005 buf[pos++] = (byte) cbuf[cpos++]; 2006 } 2007 off += n; 2008 } 2009 } 2010 2011 public void writeChars(String s) throws IOException { 2012 int endoff = s.length(); 2013 for (int off = 0; off < endoff; ) { 2014 int csize = Math.min(endoff - off, CHAR_BUF_SIZE); 2015 s.getChars(off, off + csize, cbuf, 0); 2016 writeChars(cbuf, 0, csize); 2017 off += csize; 2018 } 2019 } 2020 2021 public void writeUTF(String s) throws IOException { 2022 writeUTF(s, getUTFLength(s)); 2023 } 2024 2025 2026 /* -------------- primitive data array output methods -------------- */ 2027 /* 2028 * The following methods write out spans of primitive data values. 2029 * Though equivalent to calling the corresponding primitive write 2030 * methods repeatedly, these methods are optimized for writing groups 2031 * of primitive data values more efficiently. 2032 */ 2033 2034 void writeBooleans(boolean[] v, int off, int len) throws IOException { 2035 int endoff = off + len; 2036 while (off < endoff) { 2037 if (pos >= MAX_BLOCK_SIZE) { 2038 drain(); 2039 } 2040 int stop = Math.min(endoff, off + (MAX_BLOCK_SIZE - pos)); 2041 while (off < stop) { 2042 Bits.putBoolean(buf, pos++, v[off++]); 2043 } 2044 } 2045 } 2046 2047 void writeChars(char[] v, int off, int len) throws IOException { 2048 int limit = MAX_BLOCK_SIZE - 2; 2049 int endoff = off + len; 2050 while (off < endoff) { 2051 if (pos <= limit) { 2052 int avail = (MAX_BLOCK_SIZE - pos) >> 1; 2053 int stop = Math.min(endoff, off + avail); 2054 while (off < stop) { 2055 Bits.putChar(buf, pos, v[off++]); 2056 pos += 2; 2057 } 2058 } else { 2059 dout.writeChar(v[off++]); 2060 } 2061 } 2062 } 2063 2064 void writeShorts(short[] v, int off, int len) throws IOException { 2065 int limit = MAX_BLOCK_SIZE - 2; 2066 int endoff = off + len; 2067 while (off < endoff) { 2068 if (pos <= limit) { 2069 int avail = (MAX_BLOCK_SIZE - pos) >> 1; 2070 int stop = Math.min(endoff, off + avail); 2071 while (off < stop) { 2072 Bits.putShort(buf, pos, v[off++]); 2073 pos += 2; 2074 } 2075 } else { 2076 dout.writeShort(v[off++]); 2077 } 2078 } 2079 } 2080 2081 void writeInts(int[] v, int off, int len) throws IOException { 2082 int limit = MAX_BLOCK_SIZE - 4; 2083 int endoff = off + len; 2084 while (off < endoff) { 2085 if (pos <= limit) { 2086 int avail = (MAX_BLOCK_SIZE - pos) >> 2; 2087 int stop = Math.min(endoff, off + avail); 2088 while (off < stop) { 2089 Bits.putInt(buf, pos, v[off++]); 2090 pos += 4; 2091 } 2092 } else { 2093 dout.writeInt(v[off++]); 2094 } 2095 } 2096 } 2097 2098 void writeFloats(float[] v, int off, int len) throws IOException { 2099 int limit = MAX_BLOCK_SIZE - 4; 2100 int endoff = off + len; 2101 while (off < endoff) { 2102 if (pos <= limit) { 2103 int avail = (MAX_BLOCK_SIZE - pos) >> 2; 2104 int stop = Math.min(endoff, off + avail); 2105 while (off < stop) { 2106 Bits.putFloat(buf, pos, v[off++]); 2107 pos += 4; 2108 } 2109 } else { 2110 dout.writeFloat(v[off++]); 2111 } 2112 } 2113 } 2114 2115 void writeLongs(long[] v, int off, int len) throws IOException { 2116 int limit = MAX_BLOCK_SIZE - 8; 2117 int endoff = off + len; 2118 while (off < endoff) { 2119 if (pos <= limit) { 2120 int avail = (MAX_BLOCK_SIZE - pos) >> 3; 2121 int stop = Math.min(endoff, off + avail); 2122 while (off < stop) { 2123 Bits.putLong(buf, pos, v[off++]); 2124 pos += 8; 2125 } 2126 } else { 2127 dout.writeLong(v[off++]); 2128 } 2129 } 2130 } 2131 2132 void writeDoubles(double[] v, int off, int len) throws IOException { 2133 int limit = MAX_BLOCK_SIZE - 8; 2134 int endoff = off + len; 2135 while (off < endoff) { 2136 if (pos <= limit) { 2137 int avail = (MAX_BLOCK_SIZE - pos) >> 3; 2138 int stop = Math.min(endoff, off + avail); 2139 while (off < stop) { 2140 Bits.putDouble(buf, pos, v[off++]); 2141 pos += 8; 2142 } 2143 } else { 2144 dout.writeDouble(v[off++]); 2145 } 2146 } 2147 } 2148 2149 /** 2150 * Returns the length in bytes of the UTF encoding of the given string. 2151 */ 2152 long getUTFLength(String s) { 2153 int len = s.length(); 2154 long utflen = 0; 2155 for (int off = 0; off < len; ) { 2156 int csize = Math.min(len - off, CHAR_BUF_SIZE); 2157 s.getChars(off, off + csize, cbuf, 0); 2158 for (int cpos = 0; cpos < csize; cpos++) { 2159 char c = cbuf[cpos]; 2160 if (c >= 0x0001 && c <= 0x007F) { 2161 utflen++; 2162 } else if (c > 0x07FF) { 2163 utflen += 3; 2164 } else { 2165 utflen += 2; 2166 } 2167 } 2168 off += csize; 2169 } 2170 return utflen; 2171 } 2172 2173 /** 2174 * Writes the given string in UTF format. This method is used in 2175 * situations where the UTF encoding length of the string is already 2176 * known; specifying it explicitly avoids a prescan of the string to 2177 * determine its UTF length. 2178 */ 2179 void writeUTF(String s, long utflen) throws IOException { 2180 if (utflen > 0xFFFFL) { 2181 throw new UTFDataFormatException(); 2182 } 2183 writeShort((int) utflen); 2184 if (utflen == (long) s.length()) { 2185 writeBytes(s); 2186 } else { 2187 writeUTFBody(s); 2188 } 2189 } 2190 2191 /** 2192 * Writes given string in "long" UTF format. "Long" UTF format is 2193 * identical to standard UTF, except that it uses an 8 byte header 2194 * (instead of the standard 2 bytes) to convey the UTF encoding length. 2195 */ 2196 void writeLongUTF(String s) throws IOException { 2197 writeLongUTF(s, getUTFLength(s)); 2198 } 2199 2200 /** 2201 * Writes given string in "long" UTF format, where the UTF encoding 2202 * length of the string is already known. 2203 */ 2204 void writeLongUTF(String s, long utflen) throws IOException { 2205 writeLong(utflen); 2206 if (utflen == (long) s.length()) { 2207 writeBytes(s); 2208 } else { 2209 writeUTFBody(s); 2210 } 2211 } 2212 2213 /** 2214 * Writes the "body" (i.e., the UTF representation minus the 2-byte or 2215 * 8-byte length header) of the UTF encoding for the given string. 2216 */ 2217 private void writeUTFBody(String s) throws IOException { 2218 int limit = MAX_BLOCK_SIZE - 3; 2219 int len = s.length(); 2220 for (int off = 0; off < len; ) { 2221 int csize = Math.min(len - off, CHAR_BUF_SIZE); 2222 s.getChars(off, off + csize, cbuf, 0); 2223 for (int cpos = 0; cpos < csize; cpos++) { 2224 char c = cbuf[cpos]; 2225 if (pos <= limit) { 2226 if (c <= 0x007F && c != 0) { 2227 buf[pos++] = (byte) c; 2228 } else if (c > 0x07FF) { 2229 buf[pos + 2] = (byte) (0x80 | ((c >> 0) & 0x3F)); 2230 buf[pos + 1] = (byte) (0x80 | ((c >> 6) & 0x3F)); 2231 buf[pos + 0] = (byte) (0xE0 | ((c >> 12) & 0x0F)); 2232 pos += 3; 2233 } else { 2234 buf[pos + 1] = (byte) (0x80 | ((c >> 0) & 0x3F)); 2235 buf[pos + 0] = (byte) (0xC0 | ((c >> 6) & 0x1F)); 2236 pos += 2; 2237 } 2238 } else { // write one byte at a time to normalize block 2239 if (c <= 0x007F && c != 0) { 2240 write(c); 2241 } else if (c > 0x07FF) { 2242 write(0xE0 | ((c >> 12) & 0x0F)); 2243 write(0x80 | ((c >> 6) & 0x3F)); 2244 write(0x80 | ((c >> 0) & 0x3F)); 2245 } else { 2246 write(0xC0 | ((c >> 6) & 0x1F)); 2247 write(0x80 | ((c >> 0) & 0x3F)); 2248 } 2249 } 2250 } 2251 off += csize; 2252 } 2253 } 2254 } 2255 2256 /** 2257 * Lightweight identity hash table which maps objects to integer handles, 2258 * assigned in ascending order. 2259 */ 2260 private static class HandleTable { 2261 2262 /* number of mappings in table/next available handle */ 2263 private int size; 2264 /* size threshold determining when to expand hash spine */ 2265 private int threshold; 2266 /* factor for computing size threshold */ 2267 private final float loadFactor; 2268 /* maps hash value -> candidate handle value */ 2269 private int[] spine; 2270 /* maps handle value -> next candidate handle value */ 2271 private int[] next; 2272 /* maps handle value -> associated object */ 2273 private Object[] objs; 2274 2275 /** 2276 * Creates new HandleTable with given capacity and load factor. 2277 */ 2278 HandleTable(int initialCapacity, float loadFactor) { 2279 this.loadFactor = loadFactor; 2280 spine = new int[initialCapacity]; 2281 next = new int[initialCapacity]; 2282 objs = new Object[initialCapacity]; 2283 threshold = (int) (initialCapacity * loadFactor); 2284 clear(); 2285 } 2286 2287 /** 2288 * Assigns next available handle to given object, and returns handle 2289 * value. Handles are assigned in ascending order starting at 0. 2290 */ 2291 int assign(Object obj) { 2292 if (size >= next.length) { 2293 growEntries(); 2294 } 2295 if (size >= threshold) { 2296 growSpine(); 2297 } 2298 insert(obj, size); 2299 return size++; 2300 } 2301 2302 /** 2303 * Looks up and returns handle associated with given object, or -1 if 2304 * no mapping found. 2305 */ 2306 int lookup(Object obj) { 2307 if (size == 0) { 2308 return -1; 2309 } 2310 int index = hash(obj) % spine.length; 2311 for (int i = spine[index]; i >= 0; i = next[i]) { 2312 if (objs[i] == obj) { 2313 return i; 2314 } 2315 } 2316 return -1; 2317 } 2318 2319 /** 2320 * Resets table to its initial (empty) state. 2321 */ 2322 void clear() { 2323 Arrays.fill(spine, -1); 2324 Arrays.fill(objs, 0, size, null); 2325 size = 0; 2326 } 2327 2328 /** 2329 * Returns the number of mappings currently in table. 2330 */ 2331 int size() { 2332 return size; 2333 } 2334 2335 /** 2336 * Inserts mapping object -> handle mapping into table. Assumes table 2337 * is large enough to accommodate new mapping. 2338 */ 2339 private void insert(Object obj, int handle) { 2340 int index = hash(obj) % spine.length; 2341 objs[handle] = obj; 2342 next[handle] = spine[index]; 2343 spine[index] = handle; 2344 } 2345 2346 /** 2347 * Expands the hash "spine" -- equivalent to increasing the number of 2348 * buckets in a conventional hash table. 2349 */ 2350 private void growSpine() { 2351 spine = new int[(spine.length << 1) + 1]; 2352 threshold = (int) (spine.length * loadFactor); 2353 Arrays.fill(spine, -1); 2354 for (int i = 0; i < size; i++) { 2355 insert(objs[i], i); 2356 } 2357 } 2358 2359 /** 2360 * Increases hash table capacity by lengthening entry arrays. 2361 */ 2362 private void growEntries() { 2363 int newLength = (next.length << 1) + 1; 2364 int[] newNext = new int[newLength]; 2365 System.arraycopy(next, 0, newNext, 0, size); 2366 next = newNext; 2367 2368 Object[] newObjs = new Object[newLength]; 2369 System.arraycopy(objs, 0, newObjs, 0, size); 2370 objs = newObjs; 2371 } 2372 2373 /** 2374 * Returns hash value for given object. 2375 */ 2376 private int hash(Object obj) { 2377 return System.identityHashCode(obj) & 0x7FFFFFFF; 2378 } 2379 } 2380 2381 /** 2382 * Lightweight identity hash table which maps objects to replacement 2383 * objects. 2384 */ 2385 private static class ReplaceTable { 2386 2387 /* maps object -> index */ 2388 private final HandleTable htab; 2389 /* maps index -> replacement object */ 2390 private Object[] reps; 2391 2392 /** 2393 * Creates new ReplaceTable with given capacity and load factor. 2394 */ 2395 ReplaceTable(int initialCapacity, float loadFactor) { 2396 htab = new HandleTable(initialCapacity, loadFactor); 2397 reps = new Object[initialCapacity]; 2398 } 2399 2400 /** 2401 * Enters mapping from object to replacement object. 2402 */ 2403 void assign(Object obj, Object rep) { 2404 int index = htab.assign(obj); 2405 while (index >= reps.length) { 2406 grow(); 2407 } 2408 reps[index] = rep; 2409 } 2410 2411 /** 2412 * Looks up and returns replacement for given object. If no 2413 * replacement is found, returns the lookup object itself. 2414 */ 2415 Object lookup(Object obj) { 2416 int index = htab.lookup(obj); 2417 return (index >= 0) ? reps[index] : obj; 2418 } 2419 2420 /** 2421 * Resets table to its initial (empty) state. 2422 */ 2423 void clear() { 2424 Arrays.fill(reps, 0, htab.size(), null); 2425 htab.clear(); 2426 } 2427 2428 /** 2429 * Returns the number of mappings currently in table. 2430 */ 2431 int size() { 2432 return htab.size(); 2433 } 2434 2435 /** 2436 * Increases table capacity. 2437 */ 2438 private void grow() { 2439 Object[] newReps = new Object[(reps.length << 1) + 1]; 2440 System.arraycopy(reps, 0, newReps, 0, reps.length); 2441 reps = newReps; 2442 } 2443 } 2444 2445 /** 2446 * Stack to keep debug information about the state of the 2447 * serialization process, for embedding in exception messages. 2448 */ 2449 private static class DebugTraceInfoStack { 2450 private final List<String> stack; 2451 2452 DebugTraceInfoStack() { 2453 stack = new ArrayList<>(); 2454 } 2455 2456 /** 2457 * Removes all of the elements from enclosed list. 2458 */ 2459 void clear() { 2460 stack.clear(); 2461 } 2462 2463 /** 2464 * Removes the object at the top of enclosed list. 2465 */ 2466 void pop() { 2467 stack.remove(stack.size()-1); 2468 } 2469 2470 /** 2471 * Pushes a String onto the top of enclosed list. 2472 */ 2473 void push(String entry) { 2474 stack.add("\t- " + entry); 2475 } 2476 2477 /** 2478 * Returns a string representation of this object 2479 */ 2480 public String toString() { 2481 StringJoiner sj = new StringJoiner("\n"); 2482 for (int i = stack.size() - 1; i >= 0; i--) { 2483 sj.add(stack.get(i)); 2484 } 2485 return sj.toString(); 2486 } 2487 } 2488 2489 }