    001package org.apache.turbine.modules.layouts;
    002
    003/*
    004 * Licensed to the Apache Software Foundation (ASF) under one
    005 * or more contributor license agreements.  See the NOTICE file
    006 * distributed with this work for additional information
    007 * regarding copyright ownership.  The ASF licenses this file
    008 * to you under the Apache License, Version 2.0 (the
    009 * "License"); you may not use this file except in compliance
    010 * with the License.  You may obtain a copy of the License at
    011 *
    012 *   http://www.apache.org/licenses/LICENSE-2.0
    013 *
    014 * Unless required by applicable law or agreed to in writing,
    015 * software distributed under the License is distributed on an
    016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    017 * KIND, either express or implied.  See the License for the
    018 * specific language governing permissions and limitations
    019 * under the License.
    020 */
    021
    022import org.apache.commons.logging.Log;
    023import org.apache.commons.logging.LogFactory;
    024import org.apache.turbine.TurbineConstants;
    025import org.apache.turbine.annotation.TurbineService;
    026import org.apache.turbine.modules.Layout;
    027import org.apache.turbine.modules.pages.DefaultPage;
    028import org.apache.turbine.pipeline.PipelineData;
    029import org.apache.turbine.services.velocity.VelocityService;
    030import org.apache.turbine.util.RunData;
    031import org.apache.turbine.util.template.TemplateNavigation;
    032import org.apache.turbine.util.template.TemplateScreen;
    033import org.apache.velocity.context.Context;
    034
    035/**
    036 * This Layout module is Turbine 2.3.3 VelocityDirectLayout (same package)
    037 * with methods added for {@link PipelineData}. It is used in Jetspeed-1 portal.
    038 *
    039 * By using this layout any view write will immediately call the provided print writer {@link RunData#getOut()} and
    040 * the HTTP servlet response will be flushed and set the committed flag. This means of course
    041 * no change to the HTTP response header will be possible afterwards. By setting the {@link RunData#setAction(String)} in the request
    042 * (not only the model, but also) additional response headers could be set, cft. {@link DefaultPage#doBuild(PipelineData)}.
    043 *
    044 * @author <a href="mailto:raphael@apache.org">Raphaël Luta</a>
    045 * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a>
    046 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
    047 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
    048 * @version $Id$
    049 */
    050public class VelocityCachedLayout
    051    extends Layout
    052{
    053    /** Logging */
    054    private static Log log = LogFactory.getLog(VelocityCachedLayout.class);
    055
    056    /** The prefix for lookup up layout pages */
    057    private String prefix = getPrefix() + "/";
    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.getOut());
    100    }
    101}
    102