/*
 * Last change: $Date: 2005/06/14 21:55:50 $
 * $Revision: 1.1 $
 *
 * Copyright (c) 2004, The Black Sheep, Department of Computer Science, The University of Auckland
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
 * Neither the name of The Black Sheep, The Department of Computer Science or The University of Auckland nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

package rescuecore;

import java.io.IOException;

/**
   The Connection interface encapsulates the sending and receiving of messages to and from the kernel.
 */
public interface Connection {
    /**
       Close the connection
	*/
    public abstract void close();

    /**
       Send a message
       @param msg The message to send
       @throws IOException if something goes wrong during sending
	*/
    public abstract void send(byte[] data) throws IOException;

    /**
       Receive a message. If there is nothing to receive then this method will wait for the specified timeout (in ms, -1 to wait forever, 0 to not wait).
       @param timeout The maximum time to wait, in ms. If this is negative then this method will wait forever (or until interrupted), if it is zero then this method will not block.
       @return The next message to be received, or null if nothing is available
       @throws IOException if there is an error during receiving
	*/
    public abstract byte[] receive(int timeout) throws IOException, InterruptedException;
}