GateKeeper.java

/*
 * Copyright 2002-2011 the original author or authors.
 *
 * 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.springframework.integration.cluster;

/**
 * Interface for the gatekeeper. Used to ensure one and only
 * one instance is master.
 * 
 * @author Gary Russell
 *
 */
public interface GateKeeper<T> {

	/**
	 * Checks if this is the master; if so, returns the object
	 * if not, throws an exception.
	 * 
	 * @param t
	 * @return
	 */
	public T dispatch(T t);
	
	/**
	 * Processes a heartbeat message on the master, updating the
	 * master status as necessary.
	 * @param heartbeat
	 */
	public void heartbeat(Heartbeat heartbeat);	
}