/*
 * Copyright 2007-2010 Sun Microsystems, Inc.
 *
 * This file is part of Project Darkstar Server.
 *
 * Project Darkstar Server is free software: you can redistribute it
 * and/or modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation and
 * distributed hereunder to you.
 *
 * Project Darkstar Server 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * --
 */

package com.sun.sgs.impl.protocol.simple;

import com.sun.sgs.protocol.ProtocolDescriptor;
import com.sun.sgs.transport.TransportDescriptor;
import java.io.Serializable;

/**
 * A protocol descriptor with an underlying transport descriptor. A
 * protocol may use this class directly or extend it, overriding methods
 * for protocol and/or transport-specific needs.
 */
public class SimpleSgsProtocolDescriptor
    implements ProtocolDescriptor, Serializable
{

    private static final long serialVersionUID = 1L;

    /** The transport descriptor for this protocol. */
    protected final TransportDescriptor transportDesc;   
        
    /**
     * Constructs an instance with the specified transport descriptor.
     *
     * @param	transportDesc transport descriptor
     */
    public SimpleSgsProtocolDescriptor(TransportDescriptor transportDesc) {
        if (transportDesc == null) {
            throw new NullPointerException("null transportDesc");
        }
        this.transportDesc = transportDesc;
    }

    /** {@inheritDoc}
     *
     * <p>This implementation returns {@code true} if the specified {@code
     * descriptor} is an instance of this class and this descriptor's
     * underlying transport descriptor is compatible with the specified
     * {@code descriptor}'s transport descriptor.
     */
    public boolean supportsProtocol(ProtocolDescriptor descriptor) {
        if (!(descriptor instanceof SimpleSgsProtocolDescriptor)) {
            return false;
	}
        
        SimpleSgsProtocolDescriptor desc =
	    (SimpleSgsProtocolDescriptor) descriptor;
        
        return transportDesc.supportsTransport(desc.transportDesc);
    }

    /**
     * Return the protocol specific connection data as a byte array. The data
     * can be used by a client to connect to a server. The format of the data
     * may be dependent on the transport configured with this protocol.
     * @return the connection data
     */
    public byte[] getConnectionData() {
	return transportDesc.getConnectionData();
    }

    /**
     * Returns a string representation of this descriptor.
     *
     * @return	a string representation of this descriptor
     */
    public String toString() {
	return "SimpleSgsProtocolDescriptor[" + transportDesc.toString() + "]";
    }
}