ObjectStreamConstants (Java Platform SE 8 )

All Known Implementing Classes:

ObjectInputStream, ObjectOutputStream
```
public interface ObjectStreamConstants
```
Constants written into the Object Serialization Stream.

Since:

JDK 1.1

Field Summary

Fields
Modifier and Type	Field and Description
`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 ObjectStreamClass flag.
`static byte`	`SC_ENUM` Bit mask for ObjectStreamClass 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_ENUM` new Enum constant.
`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
```
static final short STREAM_MAGIC
```
    Magic number that is written to the stream header.
    
    See Also:
    
    Constant Field Values
  - STREAM_VERSION
```
static final short STREAM_VERSION
```
    Version number that is written to the stream header.
    
    See Also:
    
    Constant Field Values
  - TC_BASE
```
static final byte TC_BASE
```
    First tag value.
    
    See Also:
    
    Constant Field Values
  - TC_NULL
```
static final byte TC_NULL
```
    Null object reference.
    
    See Also:
    
    Constant Field Values
  - TC_REFERENCE
```
static final byte TC_REFERENCE
```
    Reference to an object already written into the stream.
    
    See Also:
    
    Constant Field Values
  - TC_CLASSDESC
```
static final byte TC_CLASSDESC
```
    new Class Descriptor.
    
    See Also:
    
    Constant Field Values
  - TC_OBJECT
```
static final byte TC_OBJECT
```
    new Object.
    
    See Also:
    
    Constant Field Values
  - TC_STRING
```
static final byte TC_STRING
```
    new String.
    
    See Also:
    
    Constant Field Values
  - TC_ARRAY
```
static final byte TC_ARRAY
```
    new Array.
    
    See Also:
    
    Constant Field Values
  - TC_CLASS
```
static final byte TC_CLASS
```
    Reference to Class.
    
    See Also:
    
    Constant Field Values
  - TC_BLOCKDATA
```
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
```
static final byte TC_ENDBLOCKDATA
```
    End of optional block data blocks for an object.
    
    See Also:
    
    Constant Field Values
  - TC_RESET
```
static final byte TC_RESET
```
    Reset stream context. All handles written into stream are reset.
    
    See Also:
    
    Constant Field Values
  - TC_BLOCKDATALONG
```
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
```
static final byte TC_EXCEPTION
```
    Exception during write.
    
    See Also:
    
    Constant Field Values
  - TC_LONGSTRING
```
static final byte TC_LONGSTRING
```
    Long string.
    
    See Also:
    
    Constant Field Values
  - TC_PROXYCLASSDESC
```
static final byte TC_PROXYCLASSDESC
```
    new Proxy Class Descriptor.
    
    See Also:
    
    Constant Field Values
  - TC_ENUM
```
static final byte TC_ENUM
```
    new Enum constant.
    
    Since:
    
    1.5
    
    See Also:
    
    Constant Field Values
  - TC_MAX
```
static final byte TC_MAX
```
    Last tag value.
    
    See Also:
    
    Constant Field Values
  - baseWireHandle
```
static final int baseWireHandle
```
    First wire handle to be assigned.
    
    See Also:
    
    Constant Field Values
  - SC_WRITE_METHOD
```
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
```
static final byte SC_BLOCK_DATA
```
    Bit mask for ObjectStreamClass 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
```
static final byte SC_SERIALIZABLE
```
    Bit mask for ObjectStreamClass flag. Indicates class is Serializable.
    
    See Also:
    
    Constant Field Values
  - SC_EXTERNALIZABLE
```
static final byte SC_EXTERNALIZABLE
```
    Bit mask for ObjectStreamClass flag. Indicates class is Externalizable.
    
    See Also:
    
    Constant Field Values
  - SC_ENUM
```
static final byte SC_ENUM
```
    Bit mask for ObjectStreamClass flag. Indicates class is an enum type.
    
    Since:
    
    1.5
    
    See Also:
    
    Constant Field Values
  - SUBSTITUTION_PERMISSION
```
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
```
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
```
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
```
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 class descriptor 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

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2024, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.

Interface ObjectStreamConstants

Field Summary

Field Detail

STREAM_MAGIC

STREAM_VERSION

TC_BASE

TC_NULL

TC_REFERENCE

TC_CLASSDESC

TC_OBJECT

TC_STRING

TC_ARRAY

TC_CLASS

TC_BLOCKDATA

TC_ENDBLOCKDATA

TC_RESET

TC_BLOCKDATALONG

TC_EXCEPTION

TC_LONGSTRING

TC_PROXYCLASSDESC

TC_ENUM

TC_MAX

baseWireHandle

SC_WRITE_METHOD

SC_BLOCK_DATA

SC_SERIALIZABLE

SC_EXTERNALIZABLE

SC_ENUM

SUBSTITUTION_PERMISSION

SUBCLASS_IMPLEMENTATION_PERMISSION

PROTOCOL_VERSION_1

PROTOCOL_VERSION_2