001package org.apache.turbine.pipeline; 002 003 004/* 005 * Licensed to the Apache Software Foundation (ASF) under one 006 * or more contributor license agreements. See the NOTICE file 007 * distributed with this work for additional information 008 * regarding copyright ownership. The ASF licenses this file 009 * to you under the Apache License, Version 2.0 (the 010 * "License"); you may not use this file except in compliance 011 * with the License. You may obtain a copy of the License at 012 * 013 * http://www.apache.org/licenses/LICENSE-2.0 014 * 015 * Unless required by applicable law or agreed to in writing, 016 * software distributed under the License is distributed on an 017 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 018 * KIND, either express or implied. See the License for the 019 * specific language governing permissions and limitations 020 * under the License. 021 */ 022 023 024import java.io.IOException; 025 026import org.apache.turbine.util.RunData; 027import org.apache.turbine.util.TurbineException; 028 029/** 030 * Valve that can be used as the basis of Valve implementations. 031 * 032 * @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a> 033 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a> 034 * @version $Id: AbstractValve.java 1773378 2016-12-09 13:19:59Z tv $ 035 */ 036public abstract class AbstractValve 037 implements Valve 038{ 039 /** 040 * Initialize this valve for use in a pipeline. 041 * 042 * @throws Exception if initialization fails 043 */ 044 @Override 045 public void initialize() 046 throws Exception 047 { 048 // empty 049 } 050 051 /** 052 * @see org.apache.turbine.pipeline.Valve#invoke(PipelineData, ValveContext) 053 */ 054 @Override 055 public abstract void invoke(PipelineData data, ValveContext context) 056 throws IOException, TurbineException; 057 058 059 /** 060 * Utility for getting RunData out of the pipelineData object. 061 * 062 * @param pipelineData Turbine request data 063 * @return the RunData object extracted from pipelineData 064 */ 065 public final RunData getRunData(PipelineData pipelineData) 066 { 067 if(!(pipelineData instanceof RunData)) 068 { 069 throw new RuntimeException("Can't cast pipelineData to rundata"); 070 } 071 return (RunData)pipelineData; 072 } 073}