1 package org.apache.turbine.pipeline;
2
3
4 /*
5 * Licensed to the Apache Software Foundation (ASF) under one
6 * or more contributor license agreements. See the NOTICE file
7 * distributed with this work for additional information
8 * regarding copyright ownership. The ASF licenses this file
9 * to you under the Apache License, Version 2.0 (the
10 * "License"); you may not use this file except in compliance
11 * with the License. You may obtain a copy of the License at
12 *
13 * http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing,
16 * software distributed under the License is distributed on an
17 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
18 * KIND, either express or implied. See the License for the
19 * specific language governing permissions and limitations
20 * under the License.
21 */
22
23
24 import java.io.IOException;
25
26 import org.apache.turbine.Turbine;
27 import org.apache.turbine.TurbineConstants;
28 import org.apache.turbine.modules.Page;
29 import org.apache.turbine.modules.PageLoader;
30 import org.apache.turbine.services.assemblerbroker.TurbineAssemblerBroker;
31 import org.apache.turbine.services.template.TemplateService;
32 import org.apache.turbine.services.template.TurbineTemplate;
33 import org.apache.turbine.util.RunData;
34 import org.apache.turbine.util.TurbineException;
35
36 /**
37 * Implements the Page Generation portion of the "Turbine classic"
38 * processing pipeline (from the Turbine 2.x series).
39 *
40 * @author <a href="mailto:epugh@opensourceConnections.com">Eric Pugh</a>
41 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
42 * @version $Id: ExecutePageValve.java 757213 2009-03-22 16:43:31Z tv $
43 */
44 public class ExecutePageValve
45 extends AbstractValve
46 {
47 private TemplateService templateService;
48 private PageLoader pageLoader;
49
50 /**
51 * Creates a new instance.
52 */
53 public ExecutePageValve()
54 {
55 // empty constructor
56 }
57
58 /**
59 * Initialize this valve for use in a pipeline.
60 *
61 * @see org.apache.turbine.pipeline.AbstractValve#initialize()
62 */
63 public void initialize() throws Exception
64 {
65 super.initialize();
66
67 this.templateService = TurbineTemplate.getService();
68 this.pageLoader = (PageLoader)TurbineAssemblerBroker.getLoader(Page.NAME);
69 }
70
71 /**
72 * @see org.apache.turbine.Valve#invoke(RunData, ValveContext)
73 */
74 public void invoke(PipelineData pipelineData, ValveContext context)
75 throws IOException, TurbineException
76 {
77 try
78 {
79 executePage(pipelineData);
80 }
81 catch (Exception e)
82 {
83 throw new TurbineException(e);
84 }
85
86 // Pass control to the next Valve in the Pipeline
87 context.invokeNext(pipelineData);
88 }
89
90 /**
91 * execute the page generation.
92 *
93 * @param data The run-time data.
94 */
95 protected void executePage(PipelineData pipelineData)
96 throws Exception
97 {
98 RunData data = getRunData(pipelineData);
99
100 // Start the execution phase. DefaultPage will execute the
101 // appropriate action as well as get the Layout from the
102 // Screen and then execute that. The Layout is then
103 // responsible for executing the Navigation and Screen
104 // modules.
105 //
106 // Note that by default, this cannot be overridden from
107 // parameters passed in via post/query data. This is for
108 // security purposes. You should really never need more
109 // than just the default page. If you do, add logic to
110 // DefaultPage to do what you want.
111
112 String defaultPage = (templateService == null)
113 ? null :templateService.getDefaultPageName(data);
114
115 if (defaultPage == null)
116 {
117 /*
118 * In this case none of the template services are running.
119 * The application may be using ECS for views, or a
120 * decendent of RawScreen is trying to produce output.
121 * If there is a 'page.default' property in the TR.props
122 * then use that, otherwise return DefaultPage which will
123 * handle ECS view scenerios and RawScreen scenerios. The
124 * app developer can still specify the 'page.default'
125 * if they wish but the DefaultPage should work in
126 * most cases.
127 */
128 defaultPage = Turbine.getConfiguration().getString(TurbineConstants.PAGE_DEFAULT_KEY,
129 TurbineConstants.PAGE_DEFAULT_DEFAULT);
130 }
131
132 pageLoader.exec(pipelineData, defaultPage);
133 }
134 }