1 /* 2 * $Id: AbstractCreateAction.java 525705 2007-04-05 05:25:08Z pbenedict $ 3 * 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 package org.apache.struts.chain.commands; 22 23 import org.apache.commons.logging.Log; 24 import org.apache.commons.logging.LogFactory; 25 import org.apache.struts.action.Action; 26 import org.apache.struts.chain.contexts.ActionContext; 27 import org.apache.struts.config.ActionConfig; 28 29 /** 30 * <p> Create (if necessary) and cache an <code>Action</code> for this 31 * request. </p> 32 * 33 * @version $Rev: 525705 $ $Date: 2005-11-12 13:01:44 -0500 (Sat, 12 Nov 2005) 34 * $ 35 */ 36 public abstract class AbstractCreateAction extends ActionCommandBase { 37 // ------------------------------------------------------ Instance Variables 38 39 /** 40 * Provide a Commons logging instance for this class. 41 */ 42 private static final Log LOG = 43 LogFactory.getLog(AbstractCreateAction.class); 44 45 // ---------------------------------------------------------- Public Methods 46 47 /** 48 * <p>Create (if necessary) and cache an <code>Action</code> for this 49 * request.</p> 50 * 51 * @param actionCtx The <code>Context</code> for the current request 52 * @return <code>false</code> so that processing continues 53 * @throws Exception if there are any problems instantiating the Action 54 * class. 55 */ 56 public boolean execute(ActionContext actionCtx) 57 throws Exception { 58 // Skip processing if the current request is not valid 59 Boolean valid = actionCtx.getFormValid(); 60 61 if ((valid == null) || !valid.booleanValue()) { 62 LOG.trace("Invalid form; not going to execute."); 63 64 return (false); 65 } 66 67 // Check to see if an action has already been created 68 if (actionCtx.getAction() != null) { 69 LOG.trace("already have an action [" + actionCtx.getAction() + "]"); 70 71 return (false); 72 } 73 74 // Look up the class name for the desired Action 75 ActionConfig actionConfig = actionCtx.getActionConfig(); 76 String type = actionConfig.getType(); 77 78 if (type == null) { 79 String command = actionConfig.getCommand(); 80 if ((command == null) && (actionConfig.getForward() == null) 81 && (actionConfig.getInclude() == null)) { 82 LOG.error("no type or command for " + actionConfig.getPath()); 83 } else { 84 LOG.trace("no type for " + actionConfig.getPath()); 85 } 86 87 return (false); 88 } 89 90 // Create (if necessary) and cache an Action instance 91 Action action = getAction(actionCtx, type, actionConfig); 92 93 if (LOG.isTraceEnabled()) { 94 LOG.trace("setting action to " + action); 95 } 96 97 actionCtx.setAction(action); 98 99 return (false); 100 } 101 102 // ------------------------------------------------------- Protected Methods 103 104 /** 105 * <p> Create and return the appropriate <code>Action</code> class for the 106 * given <code>type</code> and <code>actionConfig</code>. </p> <p> NOTE: 107 * The dependence on ActionServlet suggests that this should be broken up 108 * along the lines of the other Abstract/concrete pairs in the 109 * org.apache.struts.chain.commands package. </p> 110 * 111 * @param context The <code>Context</code> for this request 112 * @param type Name of class to instantiate 113 * @param actionConfig The {@link ActionConfig} for this request 114 * @return Instantiated Action class 115 * @throws Exception if there are any problems instantiating the Action 116 * class. 117 */ 118 protected abstract Action getAction(ActionContext context, String type, 119 ActionConfig actionConfig) 120 throws Exception; 121 }