| // Copyright 2004 The Apache 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 org.apache.tapestry.engine; |
| |
| import java.io.IOException; |
| |
| import javax.servlet.ServletException; |
| import javax.servlet.http.HttpSession; |
| |
| import org.apache.tapestry.ApplicationRuntimeException; |
| import org.apache.tapestry.IAction; |
| import org.apache.tapestry.IComponent; |
| import org.apache.tapestry.IPage; |
| import org.apache.tapestry.IRequestCycle; |
| import org.apache.tapestry.StaleSessionException; |
| import org.apache.tapestry.Tapestry; |
| import org.apache.tapestry.request.ResponseOutputStream; |
| |
| /** |
| * A context-sensitive service related to {@link org.apache.tapestry.form.Form} |
| * and {@link org.apache.tapestry.link.ActionLink}. Encodes |
| * the page, component and an action id in the service context. |
| * |
| * @author Howard Lewis Ship |
| * @version $Id$ |
| * @since 1.0.9 |
| * |
| **/ |
| |
| public class ActionService extends AbstractService |
| { |
| /** |
| * Encoded into URL if engine was stateful. |
| * |
| * @since 3.0 |
| **/ |
| |
| private static final String STATEFUL_ON = "1"; |
| |
| /** |
| * Encoded into URL if engine was not stateful. |
| * |
| * @since 3.0 |
| **/ |
| |
| private static final String STATEFUL_OFF = "0"; |
| |
| public ILink getLink(IRequestCycle cycle, IComponent component, Object[] parameters) |
| { |
| if (parameters == null || parameters.length != 1) |
| throw new IllegalArgumentException( |
| Tapestry.format("service-single-parameter", Tapestry.ACTION_SERVICE)); |
| |
| String stateful = cycle.getEngine().isStateful() ? STATEFUL_ON : STATEFUL_OFF; |
| IPage componentPage = component.getPage(); |
| IPage responsePage = cycle.getPage(); |
| |
| boolean complex = (componentPage != responsePage); |
| |
| String[] serviceContext = new String[complex ? 5 : 4]; |
| |
| int i = 0; |
| |
| serviceContext[i++] = stateful; |
| serviceContext[i++] = responsePage.getPageName(); |
| serviceContext[i++] = (String) parameters[0]; |
| |
| // Because of Block/InsertBlock, the component may not be on |
| // the same page as the response page and we need to make |
| // allowances for this. |
| |
| if (complex) |
| serviceContext[i++] = componentPage.getPageName(); |
| |
| serviceContext[i++] = component.getIdPath(); |
| |
| return constructLink(cycle, Tapestry.ACTION_SERVICE, serviceContext, null, true); |
| } |
| |
| public void service( |
| IEngineServiceView engine, |
| IRequestCycle cycle, |
| ResponseOutputStream output) |
| throws ServletException, IOException |
| { |
| IAction action = null; |
| String componentPageName; |
| int count = 0; |
| |
| String[] serviceContext = getServiceContext(cycle.getRequestContext()); |
| |
| if (serviceContext != null) |
| count = serviceContext.length; |
| |
| if (count != 4 && count != 5) |
| throw new ApplicationRuntimeException( |
| Tapestry.getMessage("ActionService.context-parameters")); |
| |
| boolean complex = count == 5; |
| |
| int i = 0; |
| String stateful = serviceContext[i++]; |
| String pageName = serviceContext[i++]; |
| String targetActionId = serviceContext[i++]; |
| |
| if (complex) |
| componentPageName = serviceContext[i++]; |
| else |
| componentPageName = pageName; |
| |
| String targetIdPath = serviceContext[i++]; |
| |
| IPage page = cycle.getPage(pageName); |
| |
| // Setup the page for the rewind, then do the rewind. |
| |
| cycle.activate(page); |
| |
| IPage componentPage = cycle.getPage(componentPageName); |
| IComponent component = componentPage.getNestedComponent(targetIdPath); |
| |
| try |
| { |
| action = (IAction) component; |
| } |
| catch (ClassCastException ex) |
| { |
| throw new ApplicationRuntimeException( |
| Tapestry.format("ActionService.component-wrong-type", component.getExtendedId()), |
| component, |
| null, |
| ex); |
| } |
| |
| // Only perform the stateful check if the application was stateful |
| // when the URL was rendered. |
| |
| if (stateful.equals(STATEFUL_ON) && action.getRequiresSession()) |
| { |
| HttpSession session = cycle.getRequestContext().getSession(); |
| |
| if (session == null || session.isNew()) |
| throw new StaleSessionException(); |
| } |
| |
| cycle.rewindPage(targetActionId, action); |
| |
| // During the rewind, a component may change the page. This will take |
| // effect during the second render, which renders the HTML response. |
| |
| // Render the response. |
| |
| engine.renderResponse(cycle, output); |
| } |
| |
| public String getName() |
| { |
| return Tapestry.ACTION_SERVICE; |
| } |
| |
| } |