CallChangeListener.java

/*
 * SIP Communicator, the OpenSource Java VoIP and Instant Messaging client.
 *
 * Distributable under LGPL license.
 * See terms of license at gnu.org.
 */
package net.java.sip.communicator.service.protocol.event;

import java.util.*;

/**
 * A call change listener receives events indicating that a call has changed and
 * a participant has either left or joined.
 *
 * @author Emil Ivov
 */
public interface CallChangeListener
    extends EventListener
{
    /**
     * Indicates that a new call participant has joined the source call.
     * @param evt the <tt>CallParticipantEvent</tt> containing the source call
     * and call participant.
     */
    public void callParticipantAdded(CallParticipantEvent evt);

    /**
     * Indicates that a call participant has left the source call.
     * @param evt the <tt>CallParticipantEvent</tt> containing the source call
     * and call participant.
     */
    public void callParticipantRemoved(CallParticipantEvent evt);

    /**
     * Indicates that a change has occurred in the state of the source call.
     * @param evt the <tt>CallChangeEvent</tt> instance containing the source
     * calls and its old and new state.
     */
    public void callStateChanged(CallChangeEvent evt);
}