--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/io/ObjectOutputStream.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,2478 @@
+/*
+ * Copyright (c) 1996, 2017, 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
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package java.io;
+
+import java.io.ObjectStreamClass.WeakClassKey;
+import java.lang.ref.ReferenceQueue;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.StringJoiner;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import static java.io.ObjectStreamClass.processQueue;
+import sun.reflect.misc.ReflectUtil;
+
+/**
+ * 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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>For example to write an object that can be read by the example in
+ * ObjectInputStream:
+ * <br>
+ * <pre>
+ * FileOutputStream fos = new FileOutputStream("t.tmp");
+ * ObjectOutputStream oos = new ObjectOutputStream(fos);
+ *
+ * oos.writeInt(12345);
+ * oos.writeObject("Today");
+ * oos.writeObject(new Date());
+ *
+ * oos.close();
+ * </pre>
+ *
+ * <p>Classes that require special handling during the serialization and
+ * deserialization process must implement special methods with these exact
+ * signatures:
+ * <br>
+ * <pre>
+ * private void readObject(java.io.ObjectInputStream stream)
+ * throws IOException, ClassNotFoundException;
+ * private void writeObject(java.io.ObjectOutputStream stream)
+ * throws IOException
+ * private void readObjectNoData()
+ * throws ObjectStreamException;
+ * </pre>
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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 <a href="{@docRoot}/../specs/serialization/output.html">
+ * Object Serialization Specification, Section 2, Object Output Classes</a>
+ * @since 1.1
+ */
+public class ObjectOutputStream
+ extends OutputStream implements ObjectOutput, ObjectStreamConstants
+{
+
+ private static class Caches {
+ /** cache of subclass security audit results */
+ static final ConcurrentMap<WeakClassKey,Boolean> subclassAudits =
+ new ConcurrentHashMap<>();
+
+ /** queue for WeakReferences to audited subclasses */
+ static final ReferenceQueue<Class<?>> subclassAuditsQueue =
+ new ReferenceQueue<>();
+ }
+
+ /** 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 SerialCallbackContext 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 =
+ java.security.AccessController.doPrivileged(
+ new sun.security.action.GetBooleanAction(
+ "sun.io.serialization.extendedDebugInfo")).booleanValue();
+
+ /**
+ * 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.
+ *
+ * <p>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 <code>out</code> is <code>null</code>
+ * @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.
+ *
+ * <p>If there is a security manager installed, this method first calls the
+ * security manager's <code>checkPermission</code> method with a
+ * <code>SerializablePermission("enableSubclassImplementation")</code>
+ * permission to ensure it's ok to enable subclassing.
+ *
+ * @throws SecurityException if a security manager exists and its
+ * <code>checkPermission</code> method denies enabling
+ * subclassing.
+ * @throws IOException if an I/O error occurs while creating this stream
+ * @see SecurityManager#checkPermission
+ * @see java.io.SerializablePermission
+ */
+ protected ObjectOutputStream() throws IOException, SecurityException {
+ SecurityManager sm = System.getSecurityManager();
+ if (sm != null) {
+ sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION);
+ }
+ bout = null;
+ handles = null;
+ subs = null;
+ enableOverride = true;
+ debugInfoStack = null;
+ }
+
+ /**
+ * Specify stream protocol version to use when writing the stream.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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:
+ * <ul>
+ * <li>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.
+ *
+ * <li>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.
+ * </ul>
+ * 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.
+ *
+ * <p>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
+ * <code>OutputStream</code>
+ */
+ public void defaultWriteObject() throws IOException {
+ SerialCallbackContext ctx = curContext;
+ if (ctx == null) {
+ throw new NotActiveException("not in call to writeObject");
+ }
+ Object curObj = ctx.getObj();
+ ObjectStreamClass curDesc = ctx.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) {
+ SerialCallbackContext ctx = curContext;
+ if (ctx == null) {
+ throw new NotActiveException("not in call to writeObject");
+ }
+ ctx.checkAndSetUsed();
+ ObjectStreamClass curDesc = ctx.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 referred 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.
+ *
+ * <p>This method is called exactly once for each unique proxy class
+ * descriptor in the stream. The default implementation of this method in
+ * <code>ObjectOutputStream</code> does nothing.
+ *
+ * <p>The corresponding method in <code>ObjectInputStream</code> is
+ * <code>resolveProxyClass</code>. For a given subclass of
+ * <code>ObjectOutputStream</code> that overrides this method, the
+ * <code>resolveProxyClass</code> method in the corresponding subclass of
+ * <code>ObjectInputStream</code> must read any data or objects written by
+ * <code>annotateProxyClass</code>.
+ *
+ * @param cl the proxy class to annotate custom data for
+ * @throws IOException any exception thrown by the underlying
+ * <code>OutputStream</code>
+ * @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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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.
+ *
+ * <p>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;
+ }
+
+ /**
+ * Enables the stream to do replacement of objects written to the stream. When
+ * enabled, the {@link #replaceObject} method is called for every object being
+ * serialized.
+ *
+ * <p>If object replacement is currently not enabled, and
+ * {@code enable} is true, and there is a security manager installed,
+ * this method first calls the security manager's
+ * {@code checkPermission} method with the
+ * {@code SerializablePermission("enableSubstitution")} permission to
+ * ensure that the caller is permitted to enable the stream to do replacement
+ * of objects written to the stream.
+ *
+ * @param enable true for enabling use of {@code replaceObject} for
+ * every object being serialized
+ * @return the previous setting before this method was invoked
+ * @throws SecurityException if a security manager exists and its
+ * {@code checkPermission} method denies enabling the stream
+ * to do replacement of objects written to the stream.
+ * @see SecurityManager#checkPermission
+ * @see java.io.SerializablePermission
+ */
+ protected boolean enableReplaceObject(boolean enable)
+ throws SecurityException
+ {
+ if (enable == enableReplace) {
+ return enable;
+ }
+ if (enable) {
+ SecurityManager sm = System.getSecurityManager();
+ if (sm != null) {
+ sm.checkPermission(SUBSTITUTION_PERMISSION);
+ }
+ }
+ enableReplace = enable;
+ return !enableReplace;
+ }
+
+ /**
+ * 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,
+ * <code>readClassDescriptor</code>, 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.
+ *
+ * <p>Note that this method will only be called if the ObjectOutputStream
+ * is not using the old serialization stream format (set by calling
+ * ObjectOutputStream's <code>useProtocolVersion</code> method). If this
+ * serialization stream is using the old format
+ * (<code>PROTOCOL_VERSION_1</code>), 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
+ * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
+ * 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 abstract static 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 <code>name</code> 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
+ * <code>boolean</code>
+ */
+ 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 <code>name</code> 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
+ * <code>byte</code>
+ */
+ 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 <code>name</code> 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
+ * <code>char</code>
+ */
+ 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 <code>name</code> 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
+ * <code>short</code>
+ */
+ 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 <code>name</code> 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
+ * <code>int</code>
+ */
+ 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 <code>name</code> 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
+ * <code>long</code>
+ */
+ 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 <code>name</code> 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
+ * <code>float</code>
+ */
+ 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 <code>name</code> 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
+ * <code>double</code>
+ */
+ 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 <code>null</code>)
+ * @throws IllegalArgumentException if <code>name</code> 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
+ * <code>PutField</code> 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 <code>PutField</code>
+ * object
+ * @deprecated This method does not write the values contained by this
+ * <code>PutField</code> object in a proper format, and may
+ * result in corruption of the serialization stream. The
+ * correct way to write <code>PutField</code> 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;
+ }
+ SecurityManager sm = System.getSecurityManager();
+ if (sm == null) {
+ return;
+ }
+ processQueue(Caches.subclassAuditsQueue, Caches.subclassAudits);
+ WeakClassKey key = new WeakClassKey(cl, Caches.subclassAuditsQueue);
+ Boolean result = Caches.subclassAudits.get(key);
+ if (result == null) {
+ result = auditSubclass(cl);
+ Caches.subclassAudits.putIfAbsent(key, result);
+ }
+ if (!result) {
+ sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION);
+ }
+ }
+
+ /**
+ * Performs reflective checks on given subclass to verify that it doesn't
+ * override security-sensitive non-final methods. Returns TRUE if subclass
+ * is "safe", FALSE otherwise.
+ */
+ private static Boolean auditSubclass(Class<?> subcl) {
+ return AccessController.doPrivileged(
+ new PrivilegedAction<>() {
+ public Boolean run() {
+ for (Class<?> cl = subcl;
+ cl != ObjectOutputStream.class;
+ cl = cl.getSuperclass())
+ {
+ try {
+ cl.getDeclaredMethod(
+ "writeUnshared", new Class<?>[] { Object.class });
+ return Boolean.FALSE;
+ } catch (NoSuchMethodException ex) {
+ }
+ try {
+ cl.getDeclaredMethod("putFields", (Class<?>[]) null);
+ return Boolean.FALSE;
+ } catch (NoSuchMethodException ex) {
+ }
+ }
+ return Boolean.TRUE;
+ }
+ }
+ );
+ }
+
+ /**
+ * 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);
+ }
+ }
+
+ private boolean isCustomSubclass() {
+ // Return true if this class is a custom subclass of ObjectOutputStream
+ return getClass().getClassLoader()
+ != ObjectOutputStream.class.getClassLoader();
+ }
+
+ /**
+ * 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);
+ if (cl != null && isCustomSubclass()) {
+ ReflectUtil.checkPackageAccess(cl);
+ }
+ 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);
+ if (cl != null && isCustomSubclass()) {
+ ReflectUtil.checkPackageAccess(cl);
+ }
+ 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");
+ }
+ SerialCallbackContext 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;
+ SerialCallbackContext oldContext = curContext;
+
+ if (extendedDebugInfo) {
+ debugInfoStack.push(
+ "custom writeObject data (class \"" +
+ slotDesc.getName() + "\")");
+ }
+ try {
+ curContext = 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
+ {
+ Class<?> cl = desc.forClass();
+ if (cl != null && obj != null && !cl.isInstance(obj)) {
+ throw new ClassCastException();
+ }
+
+ desc.checkDefaultSerialize();
+
+ int primDataSize = desc.getPrimDataSize();
+ if (primDataSize > 0) {
+ if (primVals == null || primVals.length < primDataSize) {
+ primVals = new byte[primDataSize];
+ }
+ desc.getPrimFieldValues(obj, primVals);
+ bout.write(primVals, 0, primDataSize, false);
+ }
+
+ int numObjFields = desc.getNumObjFields();
+ if (numObjFields > 0) {
+ ObjectStreamField[] fields = desc.getFields(false);
+ Object[] objVals = new Object[numObjFields];
+ 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<String> 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() {
+ StringJoiner sj = new StringJoiner("\n");
+ for (int i = stack.size() - 1; i >= 0; i--) {
+ sj.add(stack.get(i));
+ }
+ return sj.toString();
+ }
+ }
+
+}