/*
* Copyright (c) 2002-2012 Alibaba Group Holding Limited.
* All rights reserved.
*
* 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 com.alibaba.citrus.service.pipeline;
/**
* 代表pipeline中的一个“阀门”。
* <p>
* 如同真实世界里的水管中的阀门，它可以控制和改变液体的流向，<code>Valve</code> 也可以控制pipeline中后续valves的执行。
* <code>Valve</code>可以决定是否继续执行后续的valves，或是中断整个pipeline的执行。
* </p>
*
* @author Michael Zhou
*/
public interface Valve {
void invoke(PipelineContext pipelineContext) throws Exception;
}