001 package org.apache.turbine.services.jsp.util;
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
024 import org.apache.commons.logging.Log;
025 import org.apache.commons.logging.LogFactory;
026 import org.apache.turbine.modules.Screen;
027 import org.apache.turbine.modules.ScreenLoader;
028 import org.apache.turbine.services.assemblerbroker.TurbineAssemblerBroker;
029 import org.apache.turbine.services.template.TurbineTemplate;
030 import org.apache.turbine.util.RunData;
031
032 /**
033 * Returns output of a Screen module. An instance of this is placed in the
034 * request by the JspLayout. This allows template authors to
035 * place the screen template within the layout.<br>
036 * Here's how it's used in a JSP template:<br>
037 * <code>
038 * <%useBean id="screen_placeholder" class="JspScreenPlaceholder" scope="request"/%>
039 * ...
040 * <%= screen_placeholder %>
041 *</code>
042 *
043 * @author <a href="john.mcnally@clearink.com">John D. McNally</a>
044 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
045 * @version $Id: JspScreenPlaceholder.java 757213 2009-03-22 16:43:31Z tv $
046 */
047 public class JspScreenPlaceholder
048 {
049 /** Logging */
050 private static Log log = LogFactory.getLog(JspNavigation.class);
051
052 /* The RunData object */
053 private RunData data;
054
055 private ScreenLoader screenLoader;
056
057 /**
058 * Constructor
059 *
060 * @param data A Rundata Object
061 */
062 public JspScreenPlaceholder(RunData data)
063 {
064 this.data = data;
065 this.screenLoader = (ScreenLoader)TurbineAssemblerBroker.getLoader(Screen.NAME);
066 }
067
068 /**
069 * builds the output of the navigation template
070 */
071 public void exec()
072 {
073 String template = null;
074 String module = null;
075 try
076 {
077 template = data.getTemplateInfo().getScreenTemplate();
078 module = TurbineTemplate.getScreenName(template);
079 screenLoader.exec(data, module);
080 }
081 catch (Exception e)
082 {
083 String message = "Error processing navigation template:" +
084 template + " using module: " + module;
085 log.error(message, e);
086 try
087 {
088 data.getResponse().getWriter().print("Error processing navigation template: "
089 + template + " using module: " + module);
090 }
091 catch (java.io.IOException ioe)
092 {
093 // ignore
094 }
095 }
096 }
097 }