/*
 * Copyright (c) 2004, 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 com.sun.corba.se.impl.ior.iiop;

import org.omg.CORBA_2_3.portable.OutputStream;

import com.sun.corba.se.impl.orbutil.ORBConstants;
import com.sun.corba.se.impl.orbutil.ORBUtility;
import com.sun.corba.se.impl.protocol.giopmsgheaders.Message;

import com.sun.corba.se.spi.orb.ORB;
import com.sun.corba.se.spi.ior.TaggedComponentBase;

/**
 * Tagged component that contains a value that indicates the Java 
 * serialization version supported by the ORB.
 *
 * ORB Java serialization uses IIOP as the transport protocol, but uses
 * Java serialization mechanism and its accompanying encodings, instead
 * of IIOP CDR serialization mechanism. Java serialization is generally
 * observed to be faster than CDR.
 */ 
public class JavaSerializationComponent extends TaggedComponentBase {

    private byte version;

    private static JavaSerializationComponent singleton;

    public static JavaSerializationComponent singleton() {
	if (singleton == null) {
	    synchronized (JavaSerializationComponent.class) {
		singleton = 
		    new JavaSerializationComponent(Message.JAVA_ENC_VERSION);
	    }
	}
	return singleton;
    }

    public JavaSerializationComponent(byte version) {
        this.version = version;
    }

    public byte javaSerializationVersion() {
	return this.version;
    }

    public void writeContents(OutputStream os) {
        os.write_octet(version);
    }
    
    public int getId() {
	return ORBConstants.TAG_JAVA_SERIALIZATION_ID;
    }

    public boolean equals(Object obj) {
	if (!(obj instanceof JavaSerializationComponent)) {
	    return false;
	}
	JavaSerializationComponent other = (JavaSerializationComponent) obj;
	return this.version == other.version;
    }

    public int hashCode() {
	return this.version;
    }
}