001package org.apache.turbine.modules.layouts;
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.TurbineConstants;
027import org.apache.turbine.annotation.TurbineService;
028import org.apache.turbine.modules.Layout;
029import org.apache.turbine.pipeline.PipelineData;
030import org.apache.turbine.services.velocity.VelocityService;
031import org.apache.turbine.util.RunData;
032import org.apache.turbine.util.template.TemplateNavigation;
033import org.apache.turbine.util.template.TemplateScreen;
034import org.apache.velocity.context.Context;
035
036/**
037 * This Layout module allows Velocity templates
038 * to be used as layouts. It will stream directly the output of
039 * the layout and navigation templates to the output writer without
040 * using a screen. Use this if you have a large page to output
041 * and won't buffer it in the memory.
042 *
043 * @author <a href="mailto:raphael@apache.org">Raphaël Luta</a>
044 * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a>
045 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
046 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
047 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
048 * @version $Id: VelocityDirectLayout.java 1706239 2015-10-01 13:18:35Z tv $
049 */
050public class VelocityDirectLayout
051    extends Layout
052{
053    /** Logging */
054    private static Log log = LogFactory.getLog(VelocityDirectLayout.class);
055
056    /** The prefix for lookup up layout pages */
057    private String prefix = Layout.PREFIX + "/";
058
059    /** Injected service instance */
060    @TurbineService
061    private VelocityService velocityService;
062
063    /**
064     * Method called by LayoutLoader.
065     *
066     *
067     * @param pipelineData PipelineData
068     * @throws Exception generic exception
069     */
070    @Override
071    public void doBuild(PipelineData pipelineData)
072        throws Exception
073    {
074        RunData data = getRunData(pipelineData);
075        // Get the context needed by Velocity.
076        Context context = velocityService.getContext(pipelineData);
077
078        // variable for the screen in the layout template
079        context.put(TurbineConstants.SCREEN_PLACEHOLDER,
080                    new TemplateScreen(data));
081
082        // variable to reference the navigation screen in the layout template
083        context.put(TurbineConstants.NAVIGATION_PLACEHOLDER,
084                    new TemplateNavigation(data));
085
086        // Grab the layout template set in the VelocityPage.
087        // If null, then use the default layout template
088        // (done by the TemplateInfo object)
089        String templateName = data.getTemplateInfo().getLayoutTemplate();
090
091        // Set the locale and content type
092        data.getResponse().setLocale(data.getLocale());
093        data.getResponse().setContentType(data.getContentType());
094
095        log.debug("Now trying to render layout " + templateName);
096
097        // Finally, generate the layout template and send it to the browser
098        velocityService.handleRequest(context,
099                prefix + templateName, data.getResponse().getOutputStream());
100    }
101
102
103}