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	/*
	* Copyright (c) 1996, 2020, 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;

	/**
	* Constants written into the Object Serialization Stream.
	*
	* @since 1.1
	*/
	public interface ObjectStreamConstants {

	/**
	* Magic number that is written to the stream header.
	*/
	static final short STREAM_MAGIC = (short)0xaced;

	/**
	* Version number that is written to the stream header.
	*/
	static final short STREAM_VERSION = 5;

	/* Each item in the stream is preceded by a tag
	*/

	/**
	* First tag value.
	*/
	static final byte TC_BASE = 0x70;

	/**
	* Null object reference.
	*/
	static final byte TC_NULL = (byte)0x70;

	/**
	* Reference to an object already written into the stream.
	*/
	static final byte TC_REFERENCE = (byte)0x71;

	/**
	* new Class Descriptor.
	*/
	static final byte TC_CLASSDESC = (byte)0x72;

	/**
	* new Object.
	*/
	static final byte TC_OBJECT = (byte)0x73;

	/**
	* new String.
	*/
	static final byte TC_STRING = (byte)0x74;

	/**
	* new Array.
	*/
	static final byte TC_ARRAY = (byte)0x75;

	/**
	* Reference to Class.
	*/
	static final byte TC_CLASS = (byte)0x76;

	/**
	* Block of optional data. Byte following tag indicates number
	* of bytes in this block data.
	*/
	static final byte TC_BLOCKDATA = (byte)0x77;

	/**
	* End of optional block data blocks for an object.
	*/
	static final byte TC_ENDBLOCKDATA = (byte)0x78;

	/**
	* Reset stream context. All handles written into stream are reset.
	*/
	static final byte TC_RESET = (byte)0x79;

	/**
	* long Block data. The long following the tag indicates the
	* number of bytes in this block data.
	*/
	static final byte TC_BLOCKDATALONG= (byte)0x7A;

	/**
	* Exception during write.
	*/
	static final byte TC_EXCEPTION = (byte)0x7B;

	/**
	* Long string.
	*/
	static final byte TC_LONGSTRING = (byte)0x7C;

	/**
	* new Proxy Class Descriptor.
	*/
	static final byte TC_PROXYCLASSDESC = (byte)0x7D;

	/**
	* new Enum constant.
	* @since 1.5
	*/
	static final byte TC_ENUM = (byte)0x7E;

	/**
	* Last tag value.
	*/
	static final byte TC_MAX = (byte)0x7E;

	/**
	* First wire handle to be assigned.
	*/
	static final int baseWireHandle = 0x7e0000;


	/******************************************************/
	/* Bit masks for ObjectStreamClass flag.*/

	/**
	* Bit mask for ObjectStreamClass flag. Indicates a Serializable class
	* defines its own writeObject method.
	*/
	static final byte SC_WRITE_METHOD = 0x01;

	/**
	* Bit mask for ObjectStreamClass flag. Indicates Externalizable data
	* written in Block Data mode.
	* Added for PROTOCOL_VERSION_2.
	*
	* @see #PROTOCOL_VERSION_2
	* @since 1.2
	*/
	static final byte SC_BLOCK_DATA = 0x08;

	/**
	* Bit mask for ObjectStreamClass flag. Indicates class is Serializable.
	*/
	static final byte SC_SERIALIZABLE = 0x02;

	/**
	* Bit mask for ObjectStreamClass flag. Indicates class is Externalizable.
	*/
	static final byte SC_EXTERNALIZABLE = 0x04;

	/**
	* Bit mask for ObjectStreamClass flag. Indicates class is an enum type.
	* @since 1.5
	*/
	static final byte SC_ENUM = 0x10;


	/* *******************************************************************/
	/* Security permissions */

	/**
	* Enable substitution of one object for another during
	* serialization/deserialization.
	*
	* @see java.io.ObjectOutputStream#enableReplaceObject(boolean)
	* @see java.io.ObjectInputStream#enableResolveObject(boolean)
	* @since 1.2
	*/
	static final SerializablePermission SUBSTITUTION_PERMISSION =
	new SerializablePermission("enableSubstitution");

	/**
	* Enable overriding of readObject and writeObject.
	*
	* @see java.io.ObjectOutputStream#writeObjectOverride(Object)
	* @see java.io.ObjectInputStream#readObjectOverride()
	* @since 1.2
	*/
	static final SerializablePermission SUBCLASS_IMPLEMENTATION_PERMISSION =
	new SerializablePermission("enableSubclassImplementation");

	/**
	* Enable setting the system-wide serial filter.
	*
	* @see java.io.ObjectInputFilter.Config#setSerialFilter(ObjectInputFilter)
	* @since 9
	*/
	static final SerializablePermission SERIAL_FILTER_PERMISSION =
	new SerializablePermission("serialFilter");

	/**
	* A Stream Protocol Version. <p>
	*
	* 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.
	*
	* @see java.io.ObjectOutputStream#useProtocolVersion(int)
	* @since 1.2
	*/
	public static final int PROTOCOL_VERSION_1 = 1;


	/**
	* A Stream Protocol Version. <p>
	*
	* 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.
	*
	* @see java.io.ObjectOutputStream#useProtocolVersion(int)
	* @see #SC_BLOCK_DATA
	* @since 1.2
	*/
	public static final int PROTOCOL_VERSION_2 = 2;
	}

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