| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.opensymphony.xwork2; |
| |
| import com.opensymphony.xwork2.interceptor.PreResultListener; |
| import com.opensymphony.xwork2.util.ValueStack; |
| |
| /** |
| * An {@link ActionInvocation} represents the execution state of an {@link Action}. It holds the Interceptors and the Action instance. |
| * By repeated re-entrant execution of the <code>invoke()</code> method, initially by the {@link ActionProxy}, then by the Interceptors, the |
| * Interceptors are all executed, and then the {@link Action} and the {@link Result}. |
| * |
| * @author Jason Carreira |
| * @see com.opensymphony.xwork2.ActionProxy |
| */ |
| public interface ActionInvocation { |
| |
| /** |
| * Get the Action associated with this ActionInvocation. |
| * |
| * @return the Action |
| */ |
| Object getAction(); |
| |
| /** |
| * Gets whether this ActionInvocation has executed before. |
| * This will be set after the Action and the Result have executed. |
| * |
| * @return <tt>true</tt> if this ActionInvocation has executed before. |
| */ |
| boolean isExecuted(); |
| |
| /** |
| * Gets the ActionContext associated with this ActionInvocation. The ActionProxy is |
| * responsible for setting this ActionContext onto the ThreadLocal before invoking |
| * the ActionInvocation and resetting the old ActionContext afterwards. |
| * |
| * @return the ActionContext. |
| */ |
| ActionContext getInvocationContext(); |
| |
| /** |
| * Get the ActionProxy holding this ActionInvocation. |
| * |
| * @return the ActionProxy. |
| */ |
| ActionProxy getProxy(); |
| |
| /** |
| * If the ActionInvocation has been executed before and the Result is an instance of {@link ActionChainResult}, this method |
| * will walk down the chain of <code>ActionChainResult</code>s until it finds a non-chain result, which will be returned. If the |
| * ActionInvocation's result has not been executed before, the Result instance will be created and populated with |
| * the result params. |
| * |
| * @return the result. |
| * @throws Exception can be thrown. |
| */ |
| Result getResult() throws Exception; |
| |
| /** |
| * Gets the result code returned from this ActionInvocation. |
| * |
| * @return the result code |
| */ |
| String getResultCode(); |
| |
| /** |
| * Sets the result code, possibly overriding the one returned by the |
| * action. |
| * |
| * <p> |
| * The "intended" purpose of this method is to allow PreResultListeners to |
| * override the result code returned by the Action. |
| * </p> |
| * |
| * <p> |
| * If this method is used before the Action executes, the Action's returned |
| * result code will override what was set. However the Action could (if |
| * specifically coded to do so) inspect the ActionInvocation to see that |
| * someone "upstream" (e.g. an Interceptor) had suggested a value as the |
| * result, and it could therefore return the same value itself. |
| * </p> |
| * |
| * <p> |
| * If this method is called between the Action execution and the Result |
| * execution, then the value set here will override the result code the |
| * action had returned. Creating an Interceptor that implements |
| * {@link PreResultListener} will give you this opportunity. |
| * </p> |
| * |
| * <p> |
| * If this method is called after the Result has been executed, it will |
| * have the effect of raising an IllegalStateException. |
| * </p> |
| * |
| * @param resultCode the result code. |
| * @throws IllegalStateException if called after the Result has been executed. |
| * @see #isExecuted() |
| */ |
| void setResultCode(String resultCode); |
| |
| /** |
| * Gets the ValueStack associated with this ActionInvocation. |
| * |
| * @return the ValueStack |
| */ |
| ValueStack getStack(); |
| |
| /** |
| * Register a {@link PreResultListener} to be notified after the Action is executed and |
| * before the Result is executed. |
| * |
| * <p> |
| * The ActionInvocation implementation must guarantee that listeners will be called in |
| * the order in which they are registered. |
| * </p> |
| * |
| * <p> |
| * Listener registration and execution does not need to be thread-safe. |
| * </p> |
| * |
| * @param listener the listener to add. |
| */ |
| void addPreResultListener(PreResultListener listener); |
| |
| /** |
| * Invokes the next step in processing this ActionInvocation. |
| * |
| * <p> |
| * If there are more Interceptors, this will call the next one. If Interceptors choose not to short-circuit |
| * ActionInvocation processing and return their own return code, they will call invoke() to allow the next Interceptor |
| * to execute. If there are no more Interceptors to be applied, the Action is executed. |
| * If the {@link ActionProxy#getExecuteResult()} method returns <tt>true</tt>, the Result is also executed. |
| * </p> |
| * |
| * @throws Exception can be thrown. |
| * @return the return code. |
| */ |
| String invoke() throws Exception; |
| |
| /** |
| * Invokes only the Action (not Interceptors or Results). |
| * |
| * <p> |
| * This is useful in rare situations where advanced usage with the interceptor/action/result workflow is |
| * being manipulated for certain functionality. |
| * </p> |
| * |
| * @return the return code. |
| * @throws Exception can be thrown. |
| */ |
| String invokeActionOnly() throws Exception; |
| |
| /** |
| * Sets the action event listener to respond to key action events. |
| * |
| * @param listener the listener. |
| */ |
| void setActionEventListener(ActionEventListener listener); |
| |
| void init(ActionProxy proxy) ; |
| |
| } |