File	Doc	Category	Size	Date	Package
ObjectOutputStream.java	API Doc	Java SE 5 API	70928	Fri Aug 26 14:57:00 BST 2005	java.io

ObjectOutputStream

• java.lang.Object
  • java.io.OutputStream

FileOutputStream fos = new FileOutputStream("t.tmp");
ObjectOutputStream oos = new ObjectOutputStream(fos);

oos.writeInt(12345);
oos.writeObject("Today");
oos.writeObject(new Date());

oos.close();

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

Fields Summary
private static final sun.misc.SoftCache	subclassAudits cache of subclass security audit results
private final BlockDataOutputStream	bout filter stream for handling block data conversion
private final HandleTable	handles obj -> wire handle map
private final ReplaceTable	subs obj -> replacement obj map
private int	protocol stream protocol version
private int	depth recursion depth
private byte[]	primVals buffer for writing primitive field values
private final boolean	enableOverride if true, invoke writeObjectOverride() instead of writeObject()
private boolean	enableReplace if true, invoke replaceObject()
private Object	curObj object currently being serialized
private ObjectStreamClass	curDesc descriptor for current class (null if in writeExternal())
private PutFieldImpl	curPut current PutField object

Constructors Summary
public ObjectOutputStream(OutputStream out) 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 see ObjectOutputStream#ObjectOutputStream() see ObjectOutputStream#putFields() see ObjectInputStream#ObjectInputStream(InputStream) 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);
protected ObjectOutputStream() 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 SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION); } bout = null; handles = null; subs = null; enableOverride = true;

Methods Summary
protected void	annotateClass(java.lang.Class cl) 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	annotateProxyClass(java.lang.Class cl) 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
private static boolean	auditSubclass(java.lang.Class subcl) 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. Boolean result = (Boolean) AccessController.doPrivileged( new PrivilegedAction() { public Object 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", new Class[0]); return Boolean.FALSE; } catch (NoSuchMethodException ex) { } } return Boolean.TRUE; } } ); return result.booleanValue();
private void	clear() Clears internal data structures. subs.clear(); handles.clear();
public void	close() 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. flush(); clear(); bout.close();
private void	defaultWriteFields(java.lang.Object obj, java.io.ObjectStreamClass desc) 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. // 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++) { writeObject0(objVals[i], fields[numPrimFields + i].isUnshared()); }
public void	defaultWriteObject() 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 if (curObj == null || curDesc == null) { throw new NotActiveException("not in call to writeObject"); } bout.setBlockDataMode(false); defaultWriteFields(curObj, curDesc); bout.setBlockDataMode(true);
private static native void	doublesToBytes(double[] src, int srcpos, byte[] dst, int dstpos, int ndoubles) Converts specified span of double values into byte values.
protected void	drain() 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 bout.drain();
protected boolean	enableReplaceObject(boolean enable) 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 if (enable == enableReplace) { return enable; } if (enable) { SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(SUBSTITUTION_PERMISSION); } } enableReplace = enable; return !enableReplace;
private static native void	floatsToBytes(float[] src, int srcpos, byte[] dst, int dstpos, int nfloats) Converts specified span of float values into byte values.
public void	flush() 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. bout.flush();
int	getProtocolVersion() Returns protocol version in use. return protocol;
public java.io.ObjectOutputStream$PutField	putFields() 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 if (curPut == null) { if (curObj == null || curDesc == null) { throw new NotActiveException("not in call to writeObject"); } curPut = new PutFieldImpl(curDesc); } return curPut;
protected java.lang.Object	replaceObject(java.lang.Object obj) 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. return obj;
public void	reset() 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. if (depth != 0) { throw new IOException("stream active"); } bout.setBlockDataMode(false); bout.writeByte(TC_RESET); clear(); bout.setBlockDataMode(true);
public void	useProtocolVersion(int version) 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 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); }
private void	verifySubclass() 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. Class cl = getClass(); synchronized (subclassAudits) { Boolean result = (Boolean) subclassAudits.get(cl); if (result == null) { /* * Note: only new Boolean instances (i.e., not Boolean.TRUE or * Boolean.FALSE) must be used as cache values, otherwise cache * entry will pin associated class. */ result = new Boolean(auditSubclass(cl)); subclassAudits.put(cl, result); } if (result.booleanValue()) { return; } } SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION); }
public void	write(int val) 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. bout.write(val);
public void	write(byte[] buf) 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. bout.write(buf, 0, buf.length, false);
public void	write(byte[] buf, int off, int len) 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. 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);
private void	writeArray(java.lang.Object array, java.io.ObjectStreamClass desc, boolean unshared) Writes given array object to stream. 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); for (int i = 0; i < len; i++) { writeObject0(objs[i], false); } }
public void	writeBoolean(boolean val) Writes a boolean. param val the boolean to be written throws IOException if I/O errors occur while writing to the underlying stream bout.writeBoolean(val);
public void	writeByte(int 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 bout.writeByte(val);
public void	writeBytes(java.lang.String str) 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 bout.writeBytes(str);
public void	writeChar(int 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 bout.writeChar(val);
public void	writeChars(java.lang.String 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 bout.writeChars(str);
private void	writeClass(java.lang.Class cl, boolean unshared) Writes representation of given class to stream. bout.writeByte(TC_CLASS); writeClassDesc(ObjectStreamClass.lookup(cl, true), false); handles.assign(unshared ? null : cl);
private void	writeClassDesc(java.io.ObjectStreamClass desc, boolean unshared) Writes representation of given class descriptor to stream. 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); }
protected void	writeClassDescriptor(java.io.ObjectStreamClass desc) 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 desc.writeNonProxy(this);
public void	writeDouble(double 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 bout.writeDouble(val);
private void	writeEnum(java.lang.Enum en, java.io.ObjectStreamClass desc, boolean unshared) Writes given enum constant to stream. 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);
private void	writeExternalData(java.io.Externalizable obj) Writes externalizable data of given object by invoking its writeExternal() method. Object oldObj = curObj; ObjectStreamClass oldDesc = curDesc; PutFieldImpl oldPut = curPut; curObj = obj; curDesc = null; curPut = null; if (protocol == PROTOCOL_VERSION_1) { obj.writeExternal(this); } else { bout.setBlockDataMode(true); obj.writeExternal(this); bout.setBlockDataMode(false); bout.writeByte(TC_ENDBLOCKDATA); } curObj = oldObj; curDesc = oldDesc; curPut = oldPut;
private void	writeFatalException(java.io.IOException ex) Attempts to write to stream fatal IOException that has caused serialization to abort. /* * 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); }
public void	writeFields() 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 if (curPut == null) { throw new NotActiveException("no current PutField object"); } bout.setBlockDataMode(false); curPut.writeFields(); bout.setBlockDataMode(true);
public void	writeFloat(float 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 bout.writeFloat(val);
private void	writeHandle(int handle) Writes given object handle to stream. bout.writeByte(TC_REFERENCE); bout.writeInt(baseWireHandle + handle);
public void	writeInt(int 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 bout.writeInt(val);
public void	writeLong(long 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 bout.writeLong(val);
private void	writeNonProxyDesc(java.io.ObjectStreamClass desc, boolean unshared) Writes class descriptor representing a standard (i.e., not a dynamic proxy) class to stream. 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);
private void	writeNull() Writes null code to stream. bout.writeByte(TC_NULL);
public final void	writeObject(java.lang.Object obj) 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. if (enableOverride) { writeObjectOverride(obj); return; } try { writeObject0(obj, false); } catch (IOException ex) { if (depth == 0) { writeFatalException(ex); } throw ex; }
private void	writeObject0(java.lang.Object obj, boolean unshared) Underlying writeObject/writeUnshared implementation. 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 { throw new NotSerializableException(cl.getName()); } } finally { depth--; bout.setBlockDataMode(oldMode); }
protected void	writeObjectOverride(java.lang.Object obj) 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
private void	writeOrdinaryObject(java.lang.Object obj, java.io.ObjectStreamClass desc, boolean unshared) Writes representation of a "ordinary" (i.e., not a String, Class, ObjectStreamClass, array, or enum constant) serializable object to the stream. 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); }
private void	writeProxyDesc(java.io.ObjectStreamClass desc, boolean unshared) Writes class descriptor representing a dynamic proxy class to stream. 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);
private void	writeSerialData(java.lang.Object obj, java.io.ObjectStreamClass desc) Writes instance data for each serializable class of given object, from superclass to subclass. ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout(); for (int i = 0; i < slots.length; i++) { ObjectStreamClass slotDesc = slots[i].desc; if (slotDesc.hasWriteObjectMethod()) { Object oldObj = curObj; ObjectStreamClass oldDesc = curDesc; PutFieldImpl oldPut = curPut; curObj = obj; curDesc = slotDesc; curPut = null; bout.setBlockDataMode(true); slotDesc.invokeWriteObject(obj, this); bout.setBlockDataMode(false); bout.writeByte(TC_ENDBLOCKDATA); curObj = oldObj; curDesc = oldDesc; curPut = oldPut; } else { defaultWriteFields(obj, slotDesc); } }
public void	writeShort(int 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 bout.writeShort(val);
protected void	writeStreamHeader() 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 bout.writeShort(STREAM_MAGIC); bout.writeShort(STREAM_VERSION);
private void	writeString(java.lang.String str, boolean unshared) Writes given string to stream, using standard or long UTF format depending on string length. 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); }
void	writeTypeString(java.lang.String str) Writes string without allowing it to be replaced in stream. Used by ObjectStreamClass to write class descriptor type strings. int handle; if (str == null) { writeNull(); } else if ((handle = handles.lookup(str)) != -1) { writeHandle(handle); } else { writeString(str, false); }
public void	writeUTF(java.lang.String 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 bout.writeUTF(str);
public void	writeUnshared(java.lang.Object obj) 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 try { writeObject0(obj, true); } catch (IOException ex) { if (depth == 0) { writeFatalException(ex); } throw ex; }