/*
 * Copyright [2013-2014] PayPal Software Foundation
 *  
 * 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 ml.shifu.guagua.coordinator.zk;

import org.apache.zookeeper.KeeperException;

/**
 * {@link GuaguaZooKeeperOperation} is used as command to process consistent logic like re-trying for all zookeeper
 * operations (create, get, ...).
 * 
 * @param <T>
 *            result for each command.
 */
public interface GuaguaZooKeeperOperation<T> {

    /**
     * Performs the operation - which may be involved multiple times if the connection to ZooKeeper closes during this
     * operation.
     * 
     * @return the result of the operation or null
     * @throws KeeperException
     *             by any zookeeper operation.
     * @throws InterruptedException
     *             by any zookeeper operation.
     */
    T execute() throws KeeperException, InterruptedException;
}