    001package 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
    024import org.apache.commons.logging.Log;
    025import org.apache.commons.logging.LogFactory;
    026import org.apache.turbine.modules.Screen;
    027import org.apache.turbine.modules.ScreenLoader;
    028import org.apache.turbine.services.assemblerbroker.TurbineAssemblerBroker;
    029import org.apache.turbine.services.template.TurbineTemplate;
    030import 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 1199089 2011-11-08 03:14:28Z tv $
    046 */
    047public class JspScreenPlaceholder
    048{
    049    /** Logging */
    050    private static Log log = LogFactory.getLog(JspNavigation.class);
    051
    052    /* The RunData object */
    053    private final RunData data;
    054
    055    private final 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.class);
    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}