BaseEmptyOption.java

/*
 * Copyright 2009-2014 Jagornet Technologies, LLC.  All Rights Reserved.
 *
 * This software is the proprietary information of Jagornet Technologies, LLC. 
 * Use is subject to license terms.
 *
 */

/*
 *   This file BaseEmptyOption.java is part of Jagornet DHCP.
 *
 *   Jagornet DHCP is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   Jagornet DHCP 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 for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with Jagornet DHCP.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
package com.jagornet.dhcp.option.base;

import java.io.IOException;
import java.nio.ByteBuffer;

import com.jagornet.dhcp.option.DhcpComparableOption;
import com.jagornet.dhcp.util.Util;
import com.jagornet.dhcp.xml.OptionExpression;

/**
 * <p>Title: BaseEmptyOption </p>
 * <p>Description: </p>.
 * 
 * @author A. Gregory Rabil
 */
public abstract class BaseEmptyOption extends BaseDhcpOption implements DhcpComparableOption
{
    /**
     * Instantiates a new empty option.
     */
    public BaseEmptyOption()
    {
        super();
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.DhcpOption#getLength()
     */
    public int getLength()
    {
        return 0;   // always zero bytes
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.Encodable#encode()
     */
    public ByteBuffer encode() throws IOException
    {
        ByteBuffer buf = super.encodeCodeAndLength();
        return (ByteBuffer) buf.flip();
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.Decodable#decode(java.nio.ByteBuffer)
     */
    public void decode(ByteBuffer buf) throws IOException
    {
    	super.decodeLength(buf);		// length is always zero
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.DhcpComparableOption#matches(com.jagornet.dhcp.xml.OptionExpression)
     */
    public boolean matches(OptionExpression expression)
    {
        if (expression == null)
            return false;
        if (expression.getCode() != this.getCode())
            return false;
        return true;
    }
    
    /* (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    public String toString()
    {
        StringBuilder sb = new StringBuilder(Util.LINE_SEPARATOR);
        sb.append(super.getName());
        return sb.toString();
    }
    
}