JavaTM 2 Platform
Std. Ed. v1.4.2

java.io
Interface ObjectStreamConstants

All Known Implementing Classes:
ObjectInputStream, ObjectOutputStream

public interface ObjectStreamConstants

Constants written into the Object Serialization Stream.

Since:
JDK 1.1

Field Summary
static int baseWireHandle
          First wire handle to be assigned.
static int PROTOCOL_VERSION_1
          A Stream Protocol Version.
static int PROTOCOL_VERSION_2
          A Stream Protocol Version.
static byte SC_BLOCK_DATA
          Bit mask for ObejctStreamClass flag.
static byte SC_EXTERNALIZABLE
          Bit mask for ObjectStreamClass flag.
static byte SC_SERIALIZABLE
          Bit mask for ObjectStreamClass flag.
static byte SC_WRITE_METHOD
          Bit mask for ObjectStreamClass flag.
static short STREAM_MAGIC
          Magic number that is written to the stream header.
static short STREAM_VERSION
          Version number that is written to the stream header.
static SerializablePermission SUBCLASS_IMPLEMENTATION_PERMISSION
          Enable overriding of readObject and writeObject.
static SerializablePermission SUBSTITUTION_PERMISSION
          Enable substitution of one object for another during serialization/deserialization.
static byte TC_ARRAY
          new Array.
static byte TC_BASE
          First tag value.
static byte TC_BLOCKDATA
          Block of optional data.
static byte TC_BLOCKDATALONG
          long Block data.
static byte TC_CLASS
          Reference to Class.
static byte TC_CLASSDESC
          new Class Descriptor.
static byte TC_ENDBLOCKDATA
          End of optional block data blocks for an object.
static byte TC_EXCEPTION
          Exception during write.
static byte TC_LONGSTRING
          Long string.
static byte TC_MAX
          Last tag value.
static byte TC_NULL
          Null object reference.
static byte TC_OBJECT
          new Object.
static byte TC_PROXYCLASSDESC
          new Proxy Class Descriptor.
static byte TC_REFERENCE
          Reference to an object already written into the stream.
static byte TC_RESET
          Reset stream context.
static byte TC_STRING
          new String.
 

Field Detail

STREAM_MAGIC

public static final short STREAM_MAGIC
Magic number that is written to the stream header.

See Also:
Constant Field Values

STREAM_VERSION

public static final short STREAM_VERSION
Version number that is written to the stream header.

See Also:
Constant Field Values

TC_BASE

public static final byte TC_BASE
First tag value.

See Also:
Constant Field Values

TC_NULL

public static final byte TC_NULL
Null object reference.

See Also:
Constant Field Values

TC_REFERENCE

public static final byte TC_REFERENCE
Reference to an object already written into the stream.

See Also:
Constant Field Values

TC_CLASSDESC

public static final byte TC_CLASSDESC
new Class Descriptor.

See Also:
Constant Field Values

TC_OBJECT

public static final byte TC_OBJECT
new Object.

See Also:
Constant Field Values

TC_STRING

public static final byte TC_STRING
new String.

See Also:
Constant Field Values

TC_ARRAY

public static final byte TC_ARRAY
new Array.

See Also:
Constant Field Values

TC_CLASS

public static final byte TC_CLASS
Reference to Class.

See Also:
Constant Field Values

TC_BLOCKDATA

public static final byte TC_BLOCKDATA
Block of optional data. Byte following tag indicates number of bytes in this block data.

See Also:
Constant Field Values

TC_ENDBLOCKDATA

public static final byte TC_ENDBLOCKDATA
End of optional block data blocks for an object.

See Also:
Constant Field Values

TC_RESET

public static final byte TC_RESET
Reset stream context. All handles written into stream are reset.

See Also:
Constant Field Values

TC_BLOCKDATALONG

public static final byte TC_BLOCKDATALONG
long Block data. The long following the tag indicates the number of bytes in this block data.

See Also:
Constant Field Values

TC_EXCEPTION

public static final byte TC_EXCEPTION
Exception during write.

See Also:
Constant Field Values

TC_LONGSTRING

public static final byte TC_LONGSTRING
Long string.

See Also:
Constant Field Values

TC_PROXYCLASSDESC

public static final byte TC_PROXYCLASSDESC
new Proxy Class Descriptor.

See Also:
Constant Field Values

TC_MAX

public static final byte TC_MAX
Last tag value.

See Also:
Constant Field Values

baseWireHandle

public static final int baseWireHandle
First wire handle to be assigned.

See Also:
Constant Field Values

SC_WRITE_METHOD

public static final byte SC_WRITE_METHOD
Bit mask for ObjectStreamClass flag. Indicates a Serializable class defines its own writeObject method.

See Also:
Constant Field Values

SC_BLOCK_DATA

public static final byte SC_BLOCK_DATA
Bit mask for ObejctStreamClass flag. Indicates Externalizable data written in Block Data mode. Added for PROTOCOL_VERSION_2.

Since:
1.2
See Also:
PROTOCOL_VERSION_2, Constant Field Values

SC_SERIALIZABLE

public static final byte SC_SERIALIZABLE
Bit mask for ObjectStreamClass flag. Indicates class is Serializable.

See Also:
Constant Field Values

SC_EXTERNALIZABLE

public static final byte SC_EXTERNALIZABLE
Bit mask for ObjectStreamClass flag. Indicates class is Externalizable.

See Also:
Constant Field Values

SUBSTITUTION_PERMISSION

public static final SerializablePermission SUBSTITUTION_PERMISSION
Enable substitution of one object for another during serialization/deserialization.

Since:
1.2
See Also:
ObjectOutputStream.enableReplaceObject(boolean), ObjectInputStream.enableResolveObject(boolean)

SUBCLASS_IMPLEMENTATION_PERMISSION

public static final SerializablePermission SUBCLASS_IMPLEMENTATION_PERMISSION
Enable overriding of readObject and writeObject.

Since:
1.2
See Also:
ObjectOutputStream.writeObjectOverride(Object), ObjectInputStream.readObjectOverride()

PROTOCOL_VERSION_1

public static final int PROTOCOL_VERSION_1
A Stream Protocol Version.

All externalizable data is written in JDK 1.1 external data format after calling this method. This version is needed to write streams containing Externalizable data that can be read by pre-JDK 1.1.6 JVMs.

Since:
1.2
See Also:
ObjectOutputStream.useProtocolVersion(int), Constant Field Values

PROTOCOL_VERSION_2

public static final int PROTOCOL_VERSION_2
A Stream Protocol Version.

This protocol is written by JVM 1.2. Externalizable data is written in block data mode and is terminated with TC_ENDBLOCKDATA. Externalizable classdescriptor flags has SC_BLOCK_DATA enabled. JVM 1.1.6 and greater can read this format change. Enables writing a nonSerializable class descriptor into the stream. The serialVersionUID of a nonSerializable class is set to 0L.

Since:
1.2
See Also:
ObjectOutputStream.useProtocolVersion(int), SC_BLOCK_DATA, Constant Field Values

JavaTM 2 Platform
Std. Ed. v1.4.2

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For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

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