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/*
 * Copyright (c) 1996, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
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package java.io;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.apidesign.bck2brwsr.emul.lang.System;

/**
 * An ObjectOutputStream writes primitive data types and graphs of Java objects
 * to an OutputStream.  The objects can be read (reconstituted) using an
 * ObjectInputStream.  Persistent storage of objects can be accomplished by
 * using a file for the stream.  If the stream is a network socket stream, the
 * objects can be reconstituted on another host or in another process.
 *
 * 

Only objects that support the java.io.Serializable interface can be * written to streams. The class of each serializable object is encoded * including the class name and signature of the class, the values of the * object's fields and arrays, and the closure of any other objects referenced * from the initial objects. * *

The method writeObject is used to write an object to the stream. Any * object, including Strings and arrays, is written with writeObject. Multiple * objects or primitives can be written to the stream. The objects must be * read back from the corresponding ObjectInputstream with the same types and * in the same order as they were written. * *

Primitive data types can also be written to the stream using the * appropriate methods from DataOutput. Strings can also be written using the * writeUTF method. * *

The default serialization mechanism for an object writes the class of the * object, the class signature, and the values of all non-transient and * non-static fields. References to other objects (except in transient or * static fields) cause those objects to be written also. Multiple references * to a single object are encoded using a reference sharing mechanism so that * graphs of objects can be restored to the same shape as when the original was * written. * *

For example to write an object that can be read by the example in * ObjectInputStream: *
*

 *      FileOutputStream fos = new FileOutputStream("t.tmp");
 *      ObjectOutputStream oos = new ObjectOutputStream(fos);
 *
 *      oos.writeInt(12345);
 *      oos.writeObject("Today");
 *      oos.writeObject(new Date());
 *
 *      oos.close();
 * 
* *

Classes that require special handling during the serialization and * deserialization process must implement special methods with these exact * signatures: *
*

 * private void readObject(java.io.ObjectInputStream stream)
 *     throws IOException, ClassNotFoundException;
 * private void writeObject(java.io.ObjectOutputStream stream)
 *     throws IOException
 * private void readObjectNoData()
 *     throws ObjectStreamException;
 * 
* *

The writeObject method is responsible for writing the state of the object * for its particular class so that the corresponding readObject method can * restore it. The method does not need to concern itself with the state * belonging to the object's superclasses or subclasses. State is saved by * writing the individual fields to the ObjectOutputStream using the * writeObject method or by using the methods for primitive data types * supported by DataOutput. * *

Serialization does not write out the fields of any object that does not * implement the java.io.Serializable interface. Subclasses of Objects that * are not serializable can be serializable. In this case the non-serializable * class must have a no-arg constructor to allow its fields to be initialized. * In this case it is the responsibility of the subclass to save and restore * the state of the non-serializable class. It is frequently the case that the * fields of that class are accessible (public, package, or protected) or that * there are get and set methods that can be used to restore the state. * *

Serialization of an object can be prevented by implementing writeObject * and readObject methods that throw the NotSerializableException. The * exception will be caught by the ObjectOutputStream and abort the * serialization process. * *

Implementing the Externalizable interface allows the object to assume * complete control over the contents and format of the object's serialized * form. The methods of the Externalizable interface, writeExternal and * readExternal, are called to save and restore the objects state. When * implemented by a class they can write and read their own state using all of * the methods of ObjectOutput and ObjectInput. It is the responsibility of * the objects to handle any versioning that occurs. * *

Enum constants are serialized differently than ordinary serializable or * externalizable objects. The serialized form of an enum constant consists * solely of its name; field values of the constant are not transmitted. To * serialize an enum constant, ObjectOutputStream writes the string returned by * the constant's name method. Like other serializable or externalizable * objects, enum constants can function as the targets of back references * appearing subsequently in the serialization stream. The process by which * enum constants are serialized cannot be customized; any class-specific * writeObject and writeReplace methods defined by enum types are ignored * during serialization. Similarly, any serialPersistentFields or * serialVersionUID field declarations are also ignored--all enum types have a * fixed serialVersionUID of 0L. * *

Primitive data, excluding serializable fields and externalizable data, is * written to the ObjectOutputStream in block-data records. A block data record * is composed of a header and data. The block data header consists of a marker * and the number of bytes to follow the header. Consecutive primitive data * writes are merged into one block-data record. The blocking factor used for * a block-data record will be 1024 bytes. Each block-data record will be * filled up to 1024 bytes, or be written whenever there is a termination of * block-data mode. Calls to the ObjectOutputStream methods writeObject, * defaultWriteObject and writeFields initially terminate any existing * block-data record. * * @author Mike Warres * @author Roger Riggs * @see java.io.DataOutput * @see java.io.ObjectInputStream * @see java.io.Serializable * @see java.io.Externalizable * @see Object Serialization Specification, Section 2, Object Output Classes * @since JDK1.1 */ public class ObjectOutputStream extends OutputStream implements ObjectOutput, ObjectStreamConstants { /** filter stream for handling block data conversion */ private final BlockDataOutputStream bout; /** obj -> wire handle map */ private final HandleTable handles; /** obj -> replacement obj map */ private final ReplaceTable subs; /** stream protocol version */ private int protocol = PROTOCOL_VERSION_2; /** recursion depth */ private int depth; /** buffer for writing primitive field values */ private byte[] primVals; /** if true, invoke writeObjectOverride() instead of writeObject() */ private final boolean enableOverride; /** if true, invoke replaceObject() */ private boolean enableReplace; // values below valid only during upcalls to writeObject()/writeExternal() /** * Context during upcalls to class-defined writeObject methods; holds * object currently being serialized and descriptor for current class. * Null when not during writeObject upcall. */ private Object curContext; /** current PutField object */ private PutFieldImpl curPut; /** custom storage for debug trace info */ private final DebugTraceInfoStack debugInfoStack; /** * value of "sun.io.serialization.extendedDebugInfo" property, * as true or false for extended information about exception's place */ private static final boolean extendedDebugInfo = false; /** * Creates an ObjectOutputStream that writes to the specified OutputStream. * This constructor writes the serialization stream header to the * underlying stream; callers may wish to flush the stream immediately to * ensure that constructors for receiving ObjectInputStreams will not block * when reading the header. * *

If a security manager is installed, this constructor will check for * the "enableSubclassImplementation" SerializablePermission when invoked * directly or indirectly by the constructor of a subclass which overrides * the ObjectOutputStream.putFields or ObjectOutputStream.writeUnshared * methods. * * @param out output stream to write to * @throws IOException if an I/O error occurs while writing stream header * @throws SecurityException if untrusted subclass illegally overrides * security-sensitive methods * @throws NullPointerException if out is null * @since 1.4 * @see ObjectOutputStream#ObjectOutputStream() * @see ObjectOutputStream#putFields() * @see ObjectInputStream#ObjectInputStream(InputStream) */ public ObjectOutputStream(OutputStream out) throws IOException { verifySubclass(); bout = new BlockDataOutputStream(out); handles = new HandleTable(10, (float) 3.00); subs = new ReplaceTable(10, (float) 3.00); enableOverride = false; writeStreamHeader(); bout.setBlockDataMode(true); if (extendedDebugInfo) { debugInfoStack = new DebugTraceInfoStack(); } else { debugInfoStack = null; } } /** * Provide a way for subclasses that are completely reimplementing * ObjectOutputStream to not have to allocate private data just used by * this implementation of ObjectOutputStream. * *

If there is a security manager installed, this method first calls the * security manager's checkPermission method with a * SerializablePermission("enableSubclassImplementation") * permission to ensure it's ok to enable subclassing. * * @throws SecurityException if a security manager exists and its * checkPermission method denies enabling * subclassing. * @see SecurityManager#checkPermission * @see java.io.SerializablePermission */ protected ObjectOutputStream() throws IOException, SecurityException { throw new SecurityException(); } /** * Specify stream protocol version to use when writing the stream. * *

This routine provides a hook to enable the current version of * Serialization to write in a format that is backwards compatible to a * previous version of the stream format. * *

Every effort will be made to avoid introducing additional * backwards incompatibilities; however, sometimes there is no * other alternative. * * @param version use ProtocolVersion from java.io.ObjectStreamConstants. * @throws IllegalStateException if called after any objects * have been serialized. * @throws IllegalArgumentException if invalid version is passed in. * @throws IOException if I/O errors occur * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_1 * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_2 * @since 1.2 */ public void useProtocolVersion(int version) throws IOException { if (handles.size() != 0) { // REMIND: implement better check for pristine stream? throw new IllegalStateException("stream non-empty"); } switch (version) { case PROTOCOL_VERSION_1: case PROTOCOL_VERSION_2: protocol = version; break; default: throw new IllegalArgumentException( "unknown version: " + version); } } /** * Write the specified object to the ObjectOutputStream. The class of the * object, the signature of the class, and the values of the non-transient * and non-static fields of the class and all of its supertypes are * written. Default serialization for a class can be overridden using the * writeObject and the readObject methods. Objects referenced by this * object are written transitively so that a complete equivalent graph of * objects can be reconstructed by an ObjectInputStream. * *

Exceptions are thrown for problems with the OutputStream and for * classes that should not be serialized. All exceptions are fatal to the * OutputStream, which is left in an indeterminate state, and it is up to * the caller to ignore or recover the stream state. * * @throws InvalidClassException Something is wrong with a class used by * serialization. * @throws NotSerializableException Some object to be serialized does not * implement the java.io.Serializable interface. * @throws IOException Any exception thrown by the underlying * OutputStream. */ public final void writeObject(Object obj) throws IOException { if (enableOverride) { writeObjectOverride(obj); return; } try { writeObject0(obj, false); } catch (IOException ex) { if (depth == 0) { writeFatalException(ex); } throw ex; } } /** * Method used by subclasses to override the default writeObject method. * This method is called by trusted subclasses of ObjectInputStream that * constructed ObjectInputStream using the protected no-arg constructor. * The subclass is expected to provide an override method with the modifier * "final". * * @param obj object to be written to the underlying stream * @throws IOException if there are I/O errors while writing to the * underlying stream * @see #ObjectOutputStream() * @see #writeObject(Object) * @since 1.2 */ protected void writeObjectOverride(Object obj) throws IOException { } /** * Writes an "unshared" object to the ObjectOutputStream. This method is * identical to writeObject, except that it always writes the given object * as a new, unique object in the stream (as opposed to a back-reference * pointing to a previously serialized instance). Specifically: *

    *
  • An object written via writeUnshared is always serialized in the * same manner as a newly appearing object (an object that has not * been written to the stream yet), regardless of whether or not the * object has been written previously. * *
  • If writeObject is used to write an object that has been previously * written with writeUnshared, the previous writeUnshared operation * is treated as if it were a write of a separate object. In other * words, ObjectOutputStream will never generate back-references to * object data written by calls to writeUnshared. *
* While writing an object via writeUnshared does not in itself guarantee a * unique reference to the object when it is deserialized, it allows a * single object to be defined multiple times in a stream, so that multiple * calls to readUnshared by the receiver will not conflict. Note that the * rules described above only apply to the base-level object written with * writeUnshared, and not to any transitively referenced sub-objects in the * object graph to be serialized. * *

ObjectOutputStream subclasses which override this method can only be * constructed in security contexts possessing the * "enableSubclassImplementation" SerializablePermission; any attempt to * instantiate such a subclass without this permission will cause a * SecurityException to be thrown. * * @param obj object to write to stream * @throws NotSerializableException if an object in the graph to be * serialized does not implement the Serializable interface * @throws InvalidClassException if a problem exists with the class of an * object to be serialized * @throws IOException if an I/O error occurs during serialization * @since 1.4 */ public void writeUnshared(Object obj) throws IOException { try { writeObject0(obj, true); } catch (IOException ex) { if (depth == 0) { writeFatalException(ex); } throw ex; } } /** * Write the non-static and non-transient fields of the current class to * this stream. This may only be called from the writeObject method of the * class being serialized. It will throw the NotActiveException if it is * called otherwise. * * @throws IOException if I/O errors occur while writing to the underlying * OutputStream */ public void defaultWriteObject() throws IOException { if ( curContext == null ) { throw new NotActiveException("not in call to writeObject"); } Object curObj = null; // curContext.getObj(); ObjectStreamClass curDesc = null; // curContext.getDesc(); bout.setBlockDataMode(false); defaultWriteFields(curObj, curDesc); bout.setBlockDataMode(true); } /** * Retrieve the object used to buffer persistent fields to be written to * the stream. The fields will be written to the stream when writeFields * method is called. * * @return an instance of the class Putfield that holds the serializable * fields * @throws IOException if I/O errors occur * @since 1.2 */ public ObjectOutputStream.PutField putFields() throws IOException { if (curPut == null) { if (curContext == null) { throw new NotActiveException("not in call to writeObject"); } Object curObj = null; // curContext.getObj(); ObjectStreamClass curDesc = null; // curContext.getDesc(); curPut = new PutFieldImpl(curDesc); } return curPut; } /** * Write the buffered fields to the stream. * * @throws IOException if I/O errors occur while writing to the underlying * stream * @throws NotActiveException Called when a classes writeObject method was * not called to write the state of the object. * @since 1.2 */ public void writeFields() throws IOException { if (curPut == null) { throw new NotActiveException("no current PutField object"); } bout.setBlockDataMode(false); curPut.writeFields(); bout.setBlockDataMode(true); } /** * Reset will disregard the state of any objects already written to the * stream. The state is reset to be the same as a new ObjectOutputStream. * The current point in the stream is marked as reset so the corresponding * ObjectInputStream will be reset at the same point. Objects previously * written to the stream will not be refered to as already being in the * stream. They will be written to the stream again. * * @throws IOException if reset() is invoked while serializing an object. */ public void reset() throws IOException { if (depth != 0) { throw new IOException("stream active"); } bout.setBlockDataMode(false); bout.writeByte(TC_RESET); clear(); bout.setBlockDataMode(true); } /** * Subclasses may implement this method to allow class data to be stored in * the stream. By default this method does nothing. The corresponding * method in ObjectInputStream is resolveClass. This method is called * exactly once for each unique class in the stream. The class name and * signature will have already been written to the stream. This method may * make free use of the ObjectOutputStream to save any representation of * the class it deems suitable (for example, the bytes of the class file). * The resolveClass method in the corresponding subclass of * ObjectInputStream must read and use any data or objects written by * annotateClass. * * @param cl the class to annotate custom data for * @throws IOException Any exception thrown by the underlying * OutputStream. */ protected void annotateClass(Class cl) throws IOException { } /** * Subclasses may implement this method to store custom data in the stream * along with descriptors for dynamic proxy classes. * *

This method is called exactly once for each unique proxy class * descriptor in the stream. The default implementation of this method in * ObjectOutputStream does nothing. * *

The corresponding method in ObjectInputStream is * resolveProxyClass. For a given subclass of * ObjectOutputStream that overrides this method, the * resolveProxyClass method in the corresponding subclass of * ObjectInputStream must read any data or objects written by * annotateProxyClass. * * @param cl the proxy class to annotate custom data for * @throws IOException any exception thrown by the underlying * OutputStream * @see ObjectInputStream#resolveProxyClass(String[]) * @since 1.3 */ protected void annotateProxyClass(Class cl) throws IOException { } /** * This method will allow trusted subclasses of ObjectOutputStream to * substitute one object for another during serialization. Replacing * objects is disabled until enableReplaceObject is called. The * enableReplaceObject method checks that the stream requesting to do * replacement can be trusted. The first occurrence of each object written * into the serialization stream is passed to replaceObject. Subsequent * references to the object are replaced by the object returned by the * original call to replaceObject. To ensure that the private state of * objects is not unintentionally exposed, only trusted streams may use * replaceObject. * *

The ObjectOutputStream.writeObject method takes a parameter of type * Object (as opposed to type Serializable) to allow for cases where * non-serializable objects are replaced by serializable ones. * *

When a subclass is replacing objects it must insure that either a * complementary substitution must be made during deserialization or that * the substituted object is compatible with every field where the * reference will be stored. Objects whose type is not a subclass of the * type of the field or array element abort the serialization by raising an * exception and the object is not be stored. * *

This method is called only once when each object is first * encountered. All subsequent references to the object will be redirected * to the new object. This method should return the object to be * substituted or the original object. * *

Null can be returned as the object to be substituted, but may cause * NullReferenceException in classes that contain references to the * original object since they may be expecting an object instead of * null. * * @param obj the object to be replaced * @return the alternate object that replaced the specified one * @throws IOException Any exception thrown by the underlying * OutputStream. */ protected Object replaceObject(Object obj) throws IOException { return obj; } /** * Enable the stream to do replacement of objects in the stream. When * enabled, the replaceObject method is called for every object being * serialized. * *

If enable is true, and there is a security manager * installed, this method first calls the security manager's * checkPermission method with a * SerializablePermission("enableSubstitution") permission to * ensure it's ok to enable the stream to do replacement of objects in the * stream. * * @param enable boolean parameter to enable replacement of objects * @return the previous setting before this method was invoked * @throws SecurityException if a security manager exists and its * checkPermission method denies enabling the stream * to do replacement of objects in the stream. * @see SecurityManager#checkPermission * @see java.io.SerializablePermission */ protected boolean enableReplaceObject(boolean enable) throws SecurityException { throw new SecurityException(); } /** * The writeStreamHeader method is provided so subclasses can append or * prepend their own header to the stream. It writes the magic number and * version to the stream. * * @throws IOException if I/O errors occur while writing to the underlying * stream */ protected void writeStreamHeader() throws IOException { bout.writeShort(STREAM_MAGIC); bout.writeShort(STREAM_VERSION); } /** * Write the specified class descriptor to the ObjectOutputStream. Class * descriptors are used to identify the classes of objects written to the * stream. Subclasses of ObjectOutputStream may override this method to * customize the way in which class descriptors are written to the * serialization stream. The corresponding method in ObjectInputStream, * readClassDescriptor, should then be overridden to * reconstitute the class descriptor from its custom stream representation. * By default, this method writes class descriptors according to the format * defined in the Object Serialization specification. * *

Note that this method will only be called if the ObjectOutputStream * is not using the old serialization stream format (set by calling * ObjectOutputStream's useProtocolVersion method). If this * serialization stream is using the old format * (PROTOCOL_VERSION_1), the class descriptor will be written * internally in a manner that cannot be overridden or customized. * * @param desc class descriptor to write to the stream * @throws IOException If an I/O error has occurred. * @see java.io.ObjectInputStream#readClassDescriptor() * @see #useProtocolVersion(int) * @see java.io.ObjectStreamConstants#PROTOCOL_VERSION_1 * @since 1.3 */ protected void writeClassDescriptor(ObjectStreamClass desc) throws IOException { desc.writeNonProxy(this); } /** * Writes a byte. This method will block until the byte is actually * written. * * @param val the byte to be written to the stream * @throws IOException If an I/O error has occurred. */ public void write(int val) throws IOException { bout.write(val); } /** * Writes an array of bytes. This method will block until the bytes are * actually written. * * @param buf the data to be written * @throws IOException If an I/O error has occurred. */ public void write(byte[] buf) throws IOException { bout.write(buf, 0, buf.length, false); } /** * Writes a sub array of bytes. * * @param buf the data to be written * @param off the start offset in the data * @param len the number of bytes that are written * @throws IOException If an I/O error has occurred. */ public void write(byte[] buf, int off, int len) throws IOException { if (buf == null) { throw new NullPointerException(); } int endoff = off + len; if (off < 0 || len < 0 || endoff > buf.length || endoff < 0) { throw new IndexOutOfBoundsException(); } bout.write(buf, off, len, false); } /** * Flushes the stream. This will write any buffered output bytes and flush * through to the underlying stream. * * @throws IOException If an I/O error has occurred. */ public void flush() throws IOException { bout.flush(); } /** * Drain any buffered data in ObjectOutputStream. Similar to flush but * does not propagate the flush to the underlying stream. * * @throws IOException if I/O errors occur while writing to the underlying * stream */ protected void drain() throws IOException { bout.drain(); } /** * Closes the stream. This method must be called to release any resources * associated with the stream. * * @throws IOException If an I/O error has occurred. */ public void close() throws IOException { flush(); clear(); bout.close(); } /** * Writes a boolean. * * @param val the boolean to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeBoolean(boolean val) throws IOException { bout.writeBoolean(val); } /** * Writes an 8 bit byte. * * @param val the byte value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeByte(int val) throws IOException { bout.writeByte(val); } /** * Writes a 16 bit short. * * @param val the short value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeShort(int val) throws IOException { bout.writeShort(val); } /** * Writes a 16 bit char. * * @param val the char value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeChar(int val) throws IOException { bout.writeChar(val); } /** * Writes a 32 bit int. * * @param val the integer value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeInt(int val) throws IOException { bout.writeInt(val); } /** * Writes a 64 bit long. * * @param val the long value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeLong(long val) throws IOException { bout.writeLong(val); } /** * Writes a 32 bit float. * * @param val the float value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeFloat(float val) throws IOException { bout.writeFloat(val); } /** * Writes a 64 bit double. * * @param val the double value to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeDouble(double val) throws IOException { bout.writeDouble(val); } /** * Writes a String as a sequence of bytes. * * @param str the String of bytes to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeBytes(String str) throws IOException { bout.writeBytes(str); } /** * Writes a String as a sequence of chars. * * @param str the String of chars to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeChars(String str) throws IOException { bout.writeChars(str); } /** * Primitive data write of this String in * modified UTF-8 * format. Note that there is a * significant difference between writing a String into the stream as * primitive data or as an Object. A String instance written by writeObject * is written into the stream as a String initially. Future writeObject() * calls write references to the string into the stream. * * @param str the String to be written * @throws IOException if I/O errors occur while writing to the underlying * stream */ public void writeUTF(String str) throws IOException { bout.writeUTF(str); } /** * Provide programmatic access to the persistent fields to be written * to ObjectOutput. * * @since 1.2 */ public static abstract class PutField { /** * Put the value of the named boolean field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * boolean */ public abstract void put(String name, boolean val); /** * Put the value of the named byte field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * byte */ public abstract void put(String name, byte val); /** * Put the value of the named char field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * char */ public abstract void put(String name, char val); /** * Put the value of the named short field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * short */ public abstract void put(String name, short val); /** * Put the value of the named int field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * int */ public abstract void put(String name, int val); /** * Put the value of the named long field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * long */ public abstract void put(String name, long val); /** * Put the value of the named float field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * float */ public abstract void put(String name, float val); /** * Put the value of the named double field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not * double */ public abstract void put(String name, double val); /** * Put the value of the named Object field into the persistent field. * * @param name the name of the serializable field * @param val the value to assign to the field * (which may be null) * @throws IllegalArgumentException if name does not * match the name of a serializable field for the class whose fields * are being written, or if the type of the named field is not a * reference type */ public abstract void put(String name, Object val); /** * Write the data and fields to the specified ObjectOutput stream, * which must be the same stream that produced this * PutField object. * * @param out the stream to write the data and fields to * @throws IOException if I/O errors occur while writing to the * underlying stream * @throws IllegalArgumentException if the specified stream is not * the same stream that produced this PutField * object * @deprecated This method does not write the values contained by this * PutField object in a proper format, and may * result in corruption of the serialization stream. The * correct way to write PutField data is by * calling the {@link java.io.ObjectOutputStream#writeFields()} * method. */ @Deprecated public abstract void write(ObjectOutput out) throws IOException; } /** * Returns protocol version in use. */ int getProtocolVersion() { return protocol; } /** * Writes string without allowing it to be replaced in stream. Used by * ObjectStreamClass to write class descriptor type strings. */ void writeTypeString(String str) throws IOException { int handle; if (str == null) { writeNull(); } else if ((handle = handles.lookup(str)) != -1) { writeHandle(handle); } else { writeString(str, false); } } /** * Verifies that this (possibly subclass) instance can be constructed * without violating security constraints: the subclass must not override * security-sensitive non-final methods, or else the * "enableSubclassImplementation" SerializablePermission is checked. */ private void verifySubclass() { Class cl = getClass(); if (cl == ObjectOutputStream.class) { return; } throw new SecurityException(); } /** * Clears internal data structures. */ private void clear() { subs.clear(); handles.clear(); } /** * Underlying writeObject/writeUnshared implementation. */ private void writeObject0(Object obj, boolean unshared) throws IOException { boolean oldMode = bout.setBlockDataMode(false); depth++; try { // handle previously written and non-replaceable objects int h; if ((obj = subs.lookup(obj)) == null) { writeNull(); return; } else if (!unshared && (h = handles.lookup(obj)) != -1) { writeHandle(h); return; } else if (obj instanceof Class) { writeClass((Class) obj, unshared); return; } else if (obj instanceof ObjectStreamClass) { writeClassDesc((ObjectStreamClass) obj, unshared); return; } // check for replacement object Object orig = obj; Class cl = obj.getClass(); ObjectStreamClass desc; for (;;) { // REMIND: skip this check for strings/arrays? Class repCl; desc = ObjectStreamClass.lookup(cl, true); if (!desc.hasWriteReplaceMethod() || (obj = desc.invokeWriteReplace(obj)) == null || (repCl = obj.getClass()) == cl) { break; } cl = repCl; } if (enableReplace) { Object rep = replaceObject(obj); if (rep != obj && rep != null) { cl = rep.getClass(); desc = ObjectStreamClass.lookup(cl, true); } obj = rep; } // if object replaced, run through original checks a second time if (obj != orig) { subs.assign(orig, obj); if (obj == null) { writeNull(); return; } else if (!unshared && (h = handles.lookup(obj)) != -1) { writeHandle(h); return; } else if (obj instanceof Class) { writeClass((Class) obj, unshared); return; } else if (obj instanceof ObjectStreamClass) { writeClassDesc((ObjectStreamClass) obj, unshared); return; } } // remaining cases if (obj instanceof String) { writeString((String) obj, unshared); } else if (cl.isArray()) { writeArray(obj, desc, unshared); } else if (obj instanceof Enum) { writeEnum((Enum) obj, desc, unshared); } else if (obj instanceof Serializable) { writeOrdinaryObject(obj, desc, unshared); } else { if (extendedDebugInfo) { throw new NotSerializableException( cl.getName() + "\n" + debugInfoStack.toString()); } else { throw new NotSerializableException(cl.getName()); } } } finally { depth--; bout.setBlockDataMode(oldMode); } } /** * Writes null code to stream. */ private void writeNull() throws IOException { bout.writeByte(TC_NULL); } /** * Writes given object handle to stream. */ private void writeHandle(int handle) throws IOException { bout.writeByte(TC_REFERENCE); bout.writeInt(baseWireHandle + handle); } /** * Writes representation of given class to stream. */ private void writeClass(Class cl, boolean unshared) throws IOException { bout.writeByte(TC_CLASS); writeClassDesc(ObjectStreamClass.lookup(cl, true), false); handles.assign(unshared ? null : cl); } /** * Writes representation of given class descriptor to stream. */ private void writeClassDesc(ObjectStreamClass desc, boolean unshared) throws IOException { int handle; if (desc == null) { writeNull(); } else if (!unshared && (handle = handles.lookup(desc)) != -1) { writeHandle(handle); } else if (desc.isProxy()) { writeProxyDesc(desc, unshared); } else { writeNonProxyDesc(desc, unshared); } } /** * Writes class descriptor representing a dynamic proxy class to stream. */ private void writeProxyDesc(ObjectStreamClass desc, boolean unshared) throws IOException { bout.writeByte(TC_PROXYCLASSDESC); handles.assign(unshared ? null : desc); Class cl = desc.forClass(); Class[] ifaces = cl.getInterfaces(); bout.writeInt(ifaces.length); for (int i = 0; i < ifaces.length; i++) { bout.writeUTF(ifaces[i].getName()); } bout.setBlockDataMode(true); annotateProxyClass(cl); bout.setBlockDataMode(false); bout.writeByte(TC_ENDBLOCKDATA); writeClassDesc(desc.getSuperDesc(), false); } /** * Writes class descriptor representing a standard (i.e., not a dynamic * proxy) class to stream. */ private void writeNonProxyDesc(ObjectStreamClass desc, boolean unshared) throws IOException { bout.writeByte(TC_CLASSDESC); handles.assign(unshared ? null : desc); if (protocol == PROTOCOL_VERSION_1) { // do not invoke class descriptor write hook with old protocol desc.writeNonProxy(this); } else { writeClassDescriptor(desc); } Class cl = desc.forClass(); bout.setBlockDataMode(true); annotateClass(cl); bout.setBlockDataMode(false); bout.writeByte(TC_ENDBLOCKDATA); writeClassDesc(desc.getSuperDesc(), false); } /** * Writes given string to stream, using standard or long UTF format * depending on string length. */ private void writeString(String str, boolean unshared) throws IOException { handles.assign(unshared ? null : str); long utflen = bout.getUTFLength(str); if (utflen <= 0xFFFF) { bout.writeByte(TC_STRING); bout.writeUTF(str, utflen); } else { bout.writeByte(TC_LONGSTRING); bout.writeLongUTF(str, utflen); } } /** * Writes given array object to stream. */ private void writeArray(Object array, ObjectStreamClass desc, boolean unshared) throws IOException { bout.writeByte(TC_ARRAY); writeClassDesc(desc, false); handles.assign(unshared ? null : array); Class ccl = desc.forClass().getComponentType(); if (ccl.isPrimitive()) { if (ccl == Integer.TYPE) { int[] ia = (int[]) array; bout.writeInt(ia.length); bout.writeInts(ia, 0, ia.length); } else if (ccl == Byte.TYPE) { byte[] ba = (byte[]) array; bout.writeInt(ba.length); bout.write(ba, 0, ba.length, true); } else if (ccl == Long.TYPE) { long[] ja = (long[]) array; bout.writeInt(ja.length); bout.writeLongs(ja, 0, ja.length); } else if (ccl == Float.TYPE) { float[] fa = (float[]) array; bout.writeInt(fa.length); bout.writeFloats(fa, 0, fa.length); } else if (ccl == Double.TYPE) { double[] da = (double[]) array; bout.writeInt(da.length); bout.writeDoubles(da, 0, da.length); } else if (ccl == Short.TYPE) { short[] sa = (short[]) array; bout.writeInt(sa.length); bout.writeShorts(sa, 0, sa.length); } else if (ccl == Character.TYPE) { char[] ca = (char[]) array; bout.writeInt(ca.length); bout.writeChars(ca, 0, ca.length); } else if (ccl == Boolean.TYPE) { boolean[] za = (boolean[]) array; bout.writeInt(za.length); bout.writeBooleans(za, 0, za.length); } else { throw new InternalError(); } } else { Object[] objs = (Object[]) array; int len = objs.length; bout.writeInt(len); if (extendedDebugInfo) { debugInfoStack.push( "array (class \"" + array.getClass().getName() + "\", size: " + len + ")"); } try { for (int i = 0; i < len; i++) { if (extendedDebugInfo) { debugInfoStack.push( "element of array (index: " + i + ")"); } try { writeObject0(objs[i], false); } finally { if (extendedDebugInfo) { debugInfoStack.pop(); } } } } finally { if (extendedDebugInfo) { debugInfoStack.pop(); } } } } /** * Writes given enum constant to stream. */ private void writeEnum(Enum en, ObjectStreamClass desc, boolean unshared) throws IOException { bout.writeByte(TC_ENUM); ObjectStreamClass sdesc = desc.getSuperDesc(); writeClassDesc((sdesc.forClass() == Enum.class) ? desc : sdesc, false); handles.assign(unshared ? null : en); writeString(en.name(), false); } /** * Writes representation of a "ordinary" (i.e., not a String, Class, * ObjectStreamClass, array, or enum constant) serializable object to the * stream. */ private void writeOrdinaryObject(Object obj, ObjectStreamClass desc, boolean unshared) throws IOException { if (extendedDebugInfo) { debugInfoStack.push( (depth == 1 ? "root " : "") + "object (class \"" + obj.getClass().getName() + "\", " + obj.toString() + ")"); } try { desc.checkSerialize(); bout.writeByte(TC_OBJECT); writeClassDesc(desc, false); handles.assign(unshared ? null : obj); if (desc.isExternalizable() && !desc.isProxy()) { writeExternalData((Externalizable) obj); } else { writeSerialData(obj, desc); } } finally { if (extendedDebugInfo) { debugInfoStack.pop(); } } } /** * Writes externalizable data of given object by invoking its * writeExternal() method. */ private void writeExternalData(Externalizable obj) throws IOException { PutFieldImpl oldPut = curPut; curPut = null; if (extendedDebugInfo) { debugInfoStack.push("writeExternal data"); } Object oldContext = curContext; try { curContext = null; if (protocol == PROTOCOL_VERSION_1) { obj.writeExternal(this); } else { bout.setBlockDataMode(true); obj.writeExternal(this); bout.setBlockDataMode(false); bout.writeByte(TC_ENDBLOCKDATA); } } finally { curContext = oldContext; if (extendedDebugInfo) { debugInfoStack.pop(); } } curPut = oldPut; } /** * Writes instance data for each serializable class of given object, from * superclass to subclass. */ private void writeSerialData(Object obj, ObjectStreamClass desc) throws IOException { ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout(); for (int i = 0; i < slots.length; i++) { ObjectStreamClass slotDesc = slots[i].desc; if (slotDesc.hasWriteObjectMethod()) { PutFieldImpl oldPut = curPut; curPut = null; Object oldContext = curContext; if (extendedDebugInfo) { debugInfoStack.push( "custom writeObject data (class \"" + slotDesc.getName() + "\")"); } try { curContext = new Object(); //new SerialCallbackContext(obj, slotDesc); bout.setBlockDataMode(true); slotDesc.invokeWriteObject(obj, this); bout.setBlockDataMode(false); bout.writeByte(TC_ENDBLOCKDATA); } finally { //curContext.setUsed(); curContext = oldContext; if (extendedDebugInfo) { debugInfoStack.pop(); } } curPut = oldPut; } else { defaultWriteFields(obj, slotDesc); } } } /** * Fetches and writes values of serializable fields of given object to * stream. The given class descriptor specifies which field values to * write, and in which order they should be written. */ private void defaultWriteFields(Object obj, ObjectStreamClass desc) throws IOException { // REMIND: perform conservative isInstance check here? desc.checkDefaultSerialize(); int primDataSize = desc.getPrimDataSize(); if (primVals == null || primVals.length < primDataSize) { primVals = new byte[primDataSize]; } desc.getPrimFieldValues(obj, primVals); bout.write(primVals, 0, primDataSize, false); ObjectStreamField[] fields = desc.getFields(false); Object[] objVals = new Object[desc.getNumObjFields()]; int numPrimFields = fields.length - objVals.length; desc.getObjFieldValues(obj, objVals); for (int i = 0; i < objVals.length; i++) { if (extendedDebugInfo) { debugInfoStack.push( "field (class \"" + desc.getName() + "\", name: \"" + fields[numPrimFields + i].getName() + "\", type: \"" + fields[numPrimFields + i].getType() + "\")"); } try { writeObject0(objVals[i], fields[numPrimFields + i].isUnshared()); } finally { if (extendedDebugInfo) { debugInfoStack.pop(); } } } } /** * Attempts to write to stream fatal IOException that has caused * serialization to abort. */ private void writeFatalException(IOException ex) throws IOException { /* * Note: the serialization specification states that if a second * IOException occurs while attempting to serialize the original fatal * exception to the stream, then a StreamCorruptedException should be * thrown (section 2.1). However, due to a bug in previous * implementations of serialization, StreamCorruptedExceptions were * rarely (if ever) actually thrown--the "root" exceptions from * underlying streams were thrown instead. This historical behavior is * followed here for consistency. */ clear(); boolean oldMode = bout.setBlockDataMode(false); try { bout.writeByte(TC_EXCEPTION); writeObject0(ex, false); clear(); } finally { bout.setBlockDataMode(oldMode); } } /** * Converts specified span of float values into byte values. */ // REMIND: remove once hotspot inlines Float.floatToIntBits private static native void floatsToBytes(float[] src, int srcpos, byte[] dst, int dstpos, int nfloats); /** * Converts specified span of double values into byte values. */ // REMIND: remove once hotspot inlines Double.doubleToLongBits private static native void doublesToBytes(double[] src, int srcpos, byte[] dst, int dstpos, int ndoubles); /** * Default PutField implementation. */ private class PutFieldImpl extends PutField { /** class descriptor describing serializable fields */ private final ObjectStreamClass desc; /** primitive field values */ private final byte[] primVals; /** object field values */ private final Object[] objVals; /** * Creates PutFieldImpl object for writing fields defined in given * class descriptor. */ PutFieldImpl(ObjectStreamClass desc) { this.desc = desc; primVals = new byte[desc.getPrimDataSize()]; objVals = new Object[desc.getNumObjFields()]; } public void put(String name, boolean val) { Bits.putBoolean(primVals, getFieldOffset(name, Boolean.TYPE), val); } public void put(String name, byte val) { primVals[getFieldOffset(name, Byte.TYPE)] = val; } public void put(String name, char val) { Bits.putChar(primVals, getFieldOffset(name, Character.TYPE), val); } public void put(String name, short val) { Bits.putShort(primVals, getFieldOffset(name, Short.TYPE), val); } public void put(String name, int val) { Bits.putInt(primVals, getFieldOffset(name, Integer.TYPE), val); } public void put(String name, float val) { Bits.putFloat(primVals, getFieldOffset(name, Float.TYPE), val); } public void put(String name, long val) { Bits.putLong(primVals, getFieldOffset(name, Long.TYPE), val); } public void put(String name, double val) { Bits.putDouble(primVals, getFieldOffset(name, Double.TYPE), val); } public void put(String name, Object val) { objVals[getFieldOffset(name, Object.class)] = val; } // deprecated in ObjectOutputStream.PutField public void write(ObjectOutput out) throws IOException { /* * Applications should *not* use this method to write PutField * data, as it will lead to stream corruption if the PutField * object writes any primitive data (since block data mode is not * unset/set properly, as is done in OOS.writeFields()). This * broken implementation is being retained solely for behavioral * compatibility, in order to support applications which use * OOS.PutField.write() for writing only non-primitive data. * * Serialization of unshared objects is not implemented here since * it is not necessary for backwards compatibility; also, unshared * semantics may not be supported by the given ObjectOutput * instance. Applications which write unshared objects using the * PutField API must use OOS.writeFields(). */ if (ObjectOutputStream.this != out) { throw new IllegalArgumentException("wrong stream"); } out.write(primVals, 0, primVals.length); ObjectStreamField[] fields = desc.getFields(false); int numPrimFields = fields.length - objVals.length; // REMIND: warn if numPrimFields > 0? for (int i = 0; i < objVals.length; i++) { if (fields[numPrimFields + i].isUnshared()) { throw new IOException("cannot write unshared object"); } out.writeObject(objVals[i]); } } /** * Writes buffered primitive data and object fields to stream. */ void writeFields() throws IOException { bout.write(primVals, 0, primVals.length, false); ObjectStreamField[] fields = desc.getFields(false); int numPrimFields = fields.length - objVals.length; for (int i = 0; i < objVals.length; i++) { if (extendedDebugInfo) { debugInfoStack.push( "field (class \"" + desc.getName() + "\", name: \"" + fields[numPrimFields + i].getName() + "\", type: \"" + fields[numPrimFields + i].getType() + "\")"); } try { writeObject0(objVals[i], fields[numPrimFields + i].isUnshared()); } finally { if (extendedDebugInfo) { debugInfoStack.pop(); } } } } /** * Returns offset of field with given name and type. A specified type * of null matches all types, Object.class matches all non-primitive * types, and any other non-null type matches assignable types only. * Throws IllegalArgumentException if no matching field found. */ private int getFieldOffset(String name, Class type) { ObjectStreamField field = desc.getField(name, type); if (field == null) { throw new IllegalArgumentException("no such field " + name + " with type " + type); } return field.getOffset(); } } /** * Buffered output stream with two modes: in default mode, outputs data in * same format as DataOutputStream; in "block data" mode, outputs data * bracketed by block data markers (see object serialization specification * for details). */ private static class BlockDataOutputStream extends OutputStream implements DataOutput { /** maximum data block length */ private static final int MAX_BLOCK_SIZE = 1024; /** maximum data block header length */ private static final int MAX_HEADER_SIZE = 5; /** (tunable) length of char buffer (for writing strings) */ private static final int CHAR_BUF_SIZE = 256; /** buffer for writing general/block data */ private final byte[] buf = new byte[MAX_BLOCK_SIZE]; /** buffer for writing block data headers */ private final byte[] hbuf = new byte[MAX_HEADER_SIZE]; /** char buffer for fast string writes */ private final char[] cbuf = new char[CHAR_BUF_SIZE]; /** block data mode */ private boolean blkmode = false; /** current offset into buf */ private int pos = 0; /** underlying output stream */ private final OutputStream out; /** loopback stream (for data writes that span data blocks) */ private final DataOutputStream dout; /** * Creates new BlockDataOutputStream on top of given underlying stream. * Block data mode is turned off by default. */ BlockDataOutputStream(OutputStream out) { this.out = out; dout = new DataOutputStream(this); } /** * Sets block data mode to the given mode (true == on, false == off) * and returns the previous mode value. If the new mode is the same as * the old mode, no action is taken. If the new mode differs from the * old mode, any buffered data is flushed before switching to the new * mode. */ boolean setBlockDataMode(boolean mode) throws IOException { if (blkmode == mode) { return blkmode; } drain(); blkmode = mode; return !blkmode; } /** * Returns true if the stream is currently in block data mode, false * otherwise. */ boolean getBlockDataMode() { return blkmode; } /* ----------------- generic output stream methods ----------------- */ /* * The following methods are equivalent to their counterparts in * OutputStream, except that they partition written data into data * blocks when in block data mode. */ public void write(int b) throws IOException { if (pos >= MAX_BLOCK_SIZE) { drain(); } buf[pos++] = (byte) b; } public void write(byte[] b) throws IOException { write(b, 0, b.length, false); } public void write(byte[] b, int off, int len) throws IOException { write(b, off, len, false); } public void flush() throws IOException { drain(); out.flush(); } public void close() throws IOException { flush(); out.close(); } /** * Writes specified span of byte values from given array. If copy is * true, copies the values to an intermediate buffer before writing * them to underlying stream (to avoid exposing a reference to the * original byte array). */ void write(byte[] b, int off, int len, boolean copy) throws IOException { if (!(copy || blkmode)) { // write directly drain(); out.write(b, off, len); return; } while (len > 0) { if (pos >= MAX_BLOCK_SIZE) { drain(); } if (len >= MAX_BLOCK_SIZE && !copy && pos == 0) { // avoid unnecessary copy writeBlockHeader(MAX_BLOCK_SIZE); out.write(b, off, MAX_BLOCK_SIZE); off += MAX_BLOCK_SIZE; len -= MAX_BLOCK_SIZE; } else { int wlen = Math.min(len, MAX_BLOCK_SIZE - pos); System.arraycopy(b, off, buf, pos, wlen); pos += wlen; off += wlen; len -= wlen; } } } /** * Writes all buffered data from this stream to the underlying stream, * but does not flush underlying stream. */ void drain() throws IOException { if (pos == 0) { return; } if (blkmode) { writeBlockHeader(pos); } out.write(buf, 0, pos); pos = 0; } /** * Writes block data header. Data blocks shorter than 256 bytes are * prefixed with a 2-byte header; all others start with a 5-byte * header. */ private void writeBlockHeader(int len) throws IOException { if (len <= 0xFF) { hbuf[0] = TC_BLOCKDATA; hbuf[1] = (byte) len; out.write(hbuf, 0, 2); } else { hbuf[0] = TC_BLOCKDATALONG; Bits.putInt(hbuf, 1, len); out.write(hbuf, 0, 5); } } /* ----------------- primitive data output methods ----------------- */ /* * The following methods are equivalent to their counterparts in * DataOutputStream, except that they partition written data into data * blocks when in block data mode. */ public void writeBoolean(boolean v) throws IOException { if (pos >= MAX_BLOCK_SIZE) { drain(); } Bits.putBoolean(buf, pos++, v); } public void writeByte(int v) throws IOException { if (pos >= MAX_BLOCK_SIZE) { drain(); } buf[pos++] = (byte) v; } public void writeChar(int v) throws IOException { if (pos + 2 <= MAX_BLOCK_SIZE) { Bits.putChar(buf, pos, (char) v); pos += 2; } else { dout.writeChar(v); } } public void writeShort(int v) throws IOException { if (pos + 2 <= MAX_BLOCK_SIZE) { Bits.putShort(buf, pos, (short) v); pos += 2; } else { dout.writeShort(v); } } public void writeInt(int v) throws IOException { if (pos + 4 <= MAX_BLOCK_SIZE) { Bits.putInt(buf, pos, v); pos += 4; } else { dout.writeInt(v); } } public void writeFloat(float v) throws IOException { if (pos + 4 <= MAX_BLOCK_SIZE) { Bits.putFloat(buf, pos, v); pos += 4; } else { dout.writeFloat(v); } } public void writeLong(long v) throws IOException { if (pos + 8 <= MAX_BLOCK_SIZE) { Bits.putLong(buf, pos, v); pos += 8; } else { dout.writeLong(v); } } public void writeDouble(double v) throws IOException { if (pos + 8 <= MAX_BLOCK_SIZE) { Bits.putDouble(buf, pos, v); pos += 8; } else { dout.writeDouble(v); } } public void writeBytes(String s) throws IOException { int endoff = s.length(); int cpos = 0; int csize = 0; for (int off = 0; off < endoff; ) { if (cpos >= csize) { cpos = 0; csize = Math.min(endoff - off, CHAR_BUF_SIZE); s.getChars(off, off + csize, cbuf, 0); } if (pos >= MAX_BLOCK_SIZE) { drain(); } int n = Math.min(csize - cpos, MAX_BLOCK_SIZE - pos); int stop = pos + n; while (pos < stop) { buf[pos++] = (byte) cbuf[cpos++]; } off += n; } } public void writeChars(String s) throws IOException { int endoff = s.length(); for (int off = 0; off < endoff; ) { int csize = Math.min(endoff - off, CHAR_BUF_SIZE); s.getChars(off, off + csize, cbuf, 0); writeChars(cbuf, 0, csize); off += csize; } } public void writeUTF(String s) throws IOException { writeUTF(s, getUTFLength(s)); } /* -------------- primitive data array output methods -------------- */ /* * The following methods write out spans of primitive data values. * Though equivalent to calling the corresponding primitive write * methods repeatedly, these methods are optimized for writing groups * of primitive data values more efficiently. */ void writeBooleans(boolean[] v, int off, int len) throws IOException { int endoff = off + len; while (off < endoff) { if (pos >= MAX_BLOCK_SIZE) { drain(); } int stop = Math.min(endoff, off + (MAX_BLOCK_SIZE - pos)); while (off < stop) { Bits.putBoolean(buf, pos++, v[off++]); } } } void writeChars(char[] v, int off, int len) throws IOException { int limit = MAX_BLOCK_SIZE - 2; int endoff = off + len; while (off < endoff) { if (pos <= limit) { int avail = (MAX_BLOCK_SIZE - pos) >> 1; int stop = Math.min(endoff, off + avail); while (off < stop) { Bits.putChar(buf, pos, v[off++]); pos += 2; } } else { dout.writeChar(v[off++]); } } } void writeShorts(short[] v, int off, int len) throws IOException { int limit = MAX_BLOCK_SIZE - 2; int endoff = off + len; while (off < endoff) { if (pos <= limit) { int avail = (MAX_BLOCK_SIZE - pos) >> 1; int stop = Math.min(endoff, off + avail); while (off < stop) { Bits.putShort(buf, pos, v[off++]); pos += 2; } } else { dout.writeShort(v[off++]); } } } void writeInts(int[] v, int off, int len) throws IOException { int limit = MAX_BLOCK_SIZE - 4; int endoff = off + len; while (off < endoff) { if (pos <= limit) { int avail = (MAX_BLOCK_SIZE - pos) >> 2; int stop = Math.min(endoff, off + avail); while (off < stop) { Bits.putInt(buf, pos, v[off++]); pos += 4; } } else { dout.writeInt(v[off++]); } } } void writeFloats(float[] v, int off, int len) throws IOException { int limit = MAX_BLOCK_SIZE - 4; int endoff = off + len; while (off < endoff) { if (pos <= limit) { int avail = (MAX_BLOCK_SIZE - pos) >> 2; int chunklen = Math.min(endoff - off, avail); floatsToBytes(v, off, buf, pos, chunklen); off += chunklen; pos += chunklen << 2; } else { dout.writeFloat(v[off++]); } } } void writeLongs(long[] v, int off, int len) throws IOException { int limit = MAX_BLOCK_SIZE - 8; int endoff = off + len; while (off < endoff) { if (pos <= limit) { int avail = (MAX_BLOCK_SIZE - pos) >> 3; int stop = Math.min(endoff, off + avail); while (off < stop) { Bits.putLong(buf, pos, v[off++]); pos += 8; } } else { dout.writeLong(v[off++]); } } } void writeDoubles(double[] v, int off, int len) throws IOException { int limit = MAX_BLOCK_SIZE - 8; int endoff = off + len; while (off < endoff) { if (pos <= limit) { int avail = (MAX_BLOCK_SIZE - pos) >> 3; int chunklen = Math.min(endoff - off, avail); doublesToBytes(v, off, buf, pos, chunklen); off += chunklen; pos += chunklen << 3; } else { dout.writeDouble(v[off++]); } } } /** * Returns the length in bytes of the UTF encoding of the given string. */ long getUTFLength(String s) { int len = s.length(); long utflen = 0; for (int off = 0; off < len; ) { int csize = Math.min(len - off, CHAR_BUF_SIZE); s.getChars(off, off + csize, cbuf, 0); for (int cpos = 0; cpos < csize; cpos++) { char c = cbuf[cpos]; if (c >= 0x0001 && c <= 0x007F) { utflen++; } else if (c > 0x07FF) { utflen += 3; } else { utflen += 2; } } off += csize; } return utflen; } /** * Writes the given string in UTF format. This method is used in * situations where the UTF encoding length of the string is already * known; specifying it explicitly avoids a prescan of the string to * determine its UTF length. */ void writeUTF(String s, long utflen) throws IOException { if (utflen > 0xFFFFL) { throw new UTFDataFormatException(); } writeShort((int) utflen); if (utflen == (long) s.length()) { writeBytes(s); } else { writeUTFBody(s); } } /** * Writes given string in "long" UTF format. "Long" UTF format is * identical to standard UTF, except that it uses an 8 byte header * (instead of the standard 2 bytes) to convey the UTF encoding length. */ void writeLongUTF(String s) throws IOException { writeLongUTF(s, getUTFLength(s)); } /** * Writes given string in "long" UTF format, where the UTF encoding * length of the string is already known. */ void writeLongUTF(String s, long utflen) throws IOException { writeLong(utflen); if (utflen == (long) s.length()) { writeBytes(s); } else { writeUTFBody(s); } } /** * Writes the "body" (i.e., the UTF representation minus the 2-byte or * 8-byte length header) of the UTF encoding for the given string. */ private void writeUTFBody(String s) throws IOException { int limit = MAX_BLOCK_SIZE - 3; int len = s.length(); for (int off = 0; off < len; ) { int csize = Math.min(len - off, CHAR_BUF_SIZE); s.getChars(off, off + csize, cbuf, 0); for (int cpos = 0; cpos < csize; cpos++) { char c = cbuf[cpos]; if (pos <= limit) { if (c <= 0x007F && c != 0) { buf[pos++] = (byte) c; } else if (c > 0x07FF) { buf[pos + 2] = (byte) (0x80 | ((c >> 0) & 0x3F)); buf[pos + 1] = (byte) (0x80 | ((c >> 6) & 0x3F)); buf[pos + 0] = (byte) (0xE0 | ((c >> 12) & 0x0F)); pos += 3; } else { buf[pos + 1] = (byte) (0x80 | ((c >> 0) & 0x3F)); buf[pos + 0] = (byte) (0xC0 | ((c >> 6) & 0x1F)); pos += 2; } } else { // write one byte at a time to normalize block if (c <= 0x007F && c != 0) { write(c); } else if (c > 0x07FF) { write(0xE0 | ((c >> 12) & 0x0F)); write(0x80 | ((c >> 6) & 0x3F)); write(0x80 | ((c >> 0) & 0x3F)); } else { write(0xC0 | ((c >> 6) & 0x1F)); write(0x80 | ((c >> 0) & 0x3F)); } } } off += csize; } } } /** * Lightweight identity hash table which maps objects to integer handles, * assigned in ascending order. */ private static class HandleTable { /* number of mappings in table/next available handle */ private int size; /* size threshold determining when to expand hash spine */ private int threshold; /* factor for computing size threshold */ private final float loadFactor; /* maps hash value -> candidate handle value */ private int[] spine; /* maps handle value -> next candidate handle value */ private int[] next; /* maps handle value -> associated object */ private Object[] objs; /** * Creates new HandleTable with given capacity and load factor. */ HandleTable(int initialCapacity, float loadFactor) { this.loadFactor = loadFactor; spine = new int[initialCapacity]; next = new int[initialCapacity]; objs = new Object[initialCapacity]; threshold = (int) (initialCapacity * loadFactor); clear(); } /** * Assigns next available handle to given object, and returns handle * value. Handles are assigned in ascending order starting at 0. */ int assign(Object obj) { if (size >= next.length) { growEntries(); } if (size >= threshold) { growSpine(); } insert(obj, size); return size++; } /** * Looks up and returns handle associated with given object, or -1 if * no mapping found. */ int lookup(Object obj) { if (size == 0) { return -1; } int index = hash(obj) % spine.length; for (int i = spine[index]; i >= 0; i = next[i]) { if (objs[i] == obj) { return i; } } return -1; } /** * Resets table to its initial (empty) state. */ void clear() { Arrays.fill(spine, -1); Arrays.fill(objs, 0, size, null); size = 0; } /** * Returns the number of mappings currently in table. */ int size() { return size; } /** * Inserts mapping object -> handle mapping into table. Assumes table * is large enough to accommodate new mapping. */ private void insert(Object obj, int handle) { int index = hash(obj) % spine.length; objs[handle] = obj; next[handle] = spine[index]; spine[index] = handle; } /** * Expands the hash "spine" -- equivalent to increasing the number of * buckets in a conventional hash table. */ private void growSpine() { spine = new int[(spine.length << 1) + 1]; threshold = (int) (spine.length * loadFactor); Arrays.fill(spine, -1); for (int i = 0; i < size; i++) { insert(objs[i], i); } } /** * Increases hash table capacity by lengthening entry arrays. */ private void growEntries() { int newLength = (next.length << 1) + 1; int[] newNext = new int[newLength]; System.arraycopy(next, 0, newNext, 0, size); next = newNext; Object[] newObjs = new Object[newLength]; System.arraycopy(objs, 0, newObjs, 0, size); objs = newObjs; } /** * Returns hash value for given object. */ private int hash(Object obj) { return System.identityHashCode(obj) & 0x7FFFFFFF; } } /** * Lightweight identity hash table which maps objects to replacement * objects. */ private static class ReplaceTable { /* maps object -> index */ private final HandleTable htab; /* maps index -> replacement object */ private Object[] reps; /** * Creates new ReplaceTable with given capacity and load factor. */ ReplaceTable(int initialCapacity, float loadFactor) { htab = new HandleTable(initialCapacity, loadFactor); reps = new Object[initialCapacity]; } /** * Enters mapping from object to replacement object. */ void assign(Object obj, Object rep) { int index = htab.assign(obj); while (index >= reps.length) { grow(); } reps[index] = rep; } /** * Looks up and returns replacement for given object. If no * replacement is found, returns the lookup object itself. */ Object lookup(Object obj) { int index = htab.lookup(obj); return (index >= 0) ? reps[index] : obj; } /** * Resets table to its initial (empty) state. */ void clear() { Arrays.fill(reps, 0, htab.size(), null); htab.clear(); } /** * Returns the number of mappings currently in table. */ int size() { return htab.size(); } /** * Increases table capacity. */ private void grow() { Object[] newReps = new Object[(reps.length << 1) + 1]; System.arraycopy(reps, 0, newReps, 0, reps.length); reps = newReps; } } /** * Stack to keep debug information about the state of the * serialization process, for embedding in exception messages. */ private static class DebugTraceInfoStack { private final List stack; DebugTraceInfoStack() { stack = new ArrayList<>(); } /** * Removes all of the elements from enclosed list. */ void clear() { stack.clear(); } /** * Removes the object at the top of enclosed list. */ void pop() { stack.remove(stack.size()-1); } /** * Pushes a String onto the top of enclosed list. */ void push(String entry) { stack.add("\t- " + entry); } /** * Returns a string representation of this object */ public String toString() { StringBuilder buffer = new StringBuilder(); if (!stack.isEmpty()) { for(int i = stack.size(); i > 0; i-- ) { buffer.append(stack.get(i-1) + ((i != 1) ? "\n" : "")); } } return buffer.toString(); } } }





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