libraries/alarm/src/main/java/org/apache/zest/library/alarm/AlarmListener.java

/*
 * Copyright 1996-2011 Niclas Hedhman.
 *
 * Licensed  under the  Apache License,  Version 2.0  (the "License");
 * you may not use  this file  except in  compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed  under the  License is distributed on an "AS IS" BASIS,
 * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY KIND, either  express  or
 * implied.
 *
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.zest.library.alarm;

/**
 * Listener for AlarmEvents.
 * <code>AlarmPoint</code> classes will fire an <code>AlarmEvent</code> whenever
 * its <code>AlarmStatus</code> is altered.
 * <p><strong>Note:</strong>Since <code>AlarmStatus</code> of an <code>AlarmPoint</code>
 * may change <i>implicitly</i>, e.g. without proper execution of tha Java
 * Virtual Machine, there are situations when the sequence of <i>old state</i>
 * and <i>new state</i> in <code>AlarmEvents</code> will not match.
 *
 * @author Niclas Hedhman
 */
public interface AlarmListener
{

    /**
     * Method signature of the AlarmListener.
     *
     * @param event the event being fired.
     */
    void alarmFired( AlarmEvent event );
}