/**@class java.io.ObjectOutputStream
implements java.io.ObjectOutput
implements java.io.ObjectStreamConstants
@extends java.io.OutputStream
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="https://docs.oracle.com/javase/8/docs/platform/serialization/spec/output.html">Object Serialization Specification, Section 2, Object Output Classes</a>
@since JDK1.1
*/
var ObjectOutputStream = {
/**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 {Number} 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
*/
useProtocolVersion : function( ) {},
/**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.
*/
writeObject : function( ) {},
/**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 {Object {Object}} 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
*/
writeUnshared : function( ) {},
/**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>
*/
defaultWriteObject : function( ) {},
/**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 {Object {java.io.ObjectOutputStream.PutField}} an instance of the class Putfield that holds the serializable
fields
@throws IOException if I/O errors occur
@since 1.2
*/
putFields : function( ) {},
/**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
*/
writeFields : function( ) {},
/**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.
*/
reset : function( ) {},
/**Writes a byte. This method will block until the byte is actually
written.
@param {Number} val the byte to be written to the stream
@throws IOException If an I/O error has occurred.
*/
write : function( ) {},
/**Writes an array of bytes. This method will block until the bytes are
actually written.
@param {Object {byte[]}} buf the data to be written
@throws IOException If an I/O error has occurred.
*/
write : function( ) {},
/**Writes a sub array of bytes.
@param {Object {byte[]}} buf the data to be written
@param {Number} off the start offset in the data
@param {Number} len the number of bytes that are written
@throws IOException If an I/O error has occurred.
*/
write : function( ) {},
/**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.
*/
flush : function( ) {},
/**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.
*/
close : function( ) {},
/**Writes a boolean.
@param {Boolean} val the boolean to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeBoolean : function( ) {},
/**Writes an 8 bit byte.
@param {Number} val the byte value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeByte : function( ) {},
/**Writes a 16 bit short.
@param {Number} val the short value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeShort : function( ) {},
/**Writes a 16 bit char.
@param {Number} val the char value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeChar : function( ) {},
/**Writes a 32 bit int.
@param {Number} val the integer value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeInt : function( ) {},
/**Writes a 64 bit long.
@param {Number} val the long value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeLong : function( ) {},
/**Writes a 32 bit float.
@param {Number} val the float value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeFloat : function( ) {},
/**Writes a 64 bit double.
@param {Number} val the double value to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeDouble : function( ) {},
/**Writes a String as a sequence of bytes.
@param {String} str the String of bytes to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeBytes : function( ) {},
/**Writes a String as a sequence of chars.
@param {String} str the String of chars to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeChars : function( ) {},
/**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 {String} str the String to be written
@throws IOException if I/O errors occur while writing to the underlying
stream
*/
writeUTF : function( ) {},
};