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    1   package org.apache.turbine.modules.layouts;
    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 org.apache.commons.lang.StringUtils;
    25  import org.apache.commons.logging.Log;
    26  import org.apache.commons.logging.LogFactory;
    27  import org.apache.turbine.TurbineConstants;
    28  import org.apache.turbine.annotation.TurbineLoader;
    29  import org.apache.turbine.annotation.TurbineService;
    30  import org.apache.turbine.modules.Layout;
    31  import org.apache.turbine.modules.Screen;
    32  import org.apache.turbine.modules.ScreenLoader;
    33  import org.apache.turbine.pipeline.PipelineData;
    34  import org.apache.turbine.services.velocity.VelocityService;
    35  import org.apache.turbine.util.RunData;
    36  import org.apache.turbine.util.template.TemplateNavigation;
    37  import org.apache.velocity.context.Context;
    38
    39  /**
    40   * This Layout module allows Velocity templates to be used as layouts.
    41   * Since dynamic content is supposed to be primarily located in
    42   * screens and navigations there should be relatively few reasons to
    43   * subclass this Layout.
    44   *
    45   * To get the same functionality as with VelocityECSLayout, you can use two
    46   * supplied VelocityMacros, TurbineHtmlHead and TurbineHtmlBodyAttributes
    47   * in your templates. These are used to put HtmlPageAttributes into a page
    48   * before rendering.
    49   *
    50   * Use these macros should be used in the Layout template like this:
    51   *
    52   * ... set things like style sheets, scripts here.
    53   * &lt;html&gt;
    54   * #TurbineHtmlHead()
    55   * &lt;body #TurbineHtmlBodyAttributes() &gt;
    56   *  .... your body information
    57   * &lt;/body&gt;
    58   * &lt;/html&gt;
    59   *
    60   * As the layout template is rendered _after_ the screen template, you
    61   * can of course, add information to the $page tool in your screen template.
    62   * This will be added correctly to the &lt;head&gt;...&lt;/head&gt; and
    63   * &lt;body&gt; tags.
    64   *
    65   * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a>
    66   * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
    67   * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
    68   * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
    69   * @version $Id: VelocityOnlyLayout.java 1709648 2015-10-20 17:08:10Z tv $
    70   */
    71  public class VelocityOnlyLayout
    72      extends Layout
    73  {
    74      /** Logging */
    75      private static Log log = LogFactory.getLog(VelocityOnlyLayout.class);
    76
    77      /** The prefix for lookup up layout pages */
    78      private final String prefix = Layout.PREFIX + "/";
    79
    80      /** Injected service instance */
    81      @TurbineService
    82      private VelocityService velocityService;
    83
    84      /** Injected loader instance */
    85      @TurbineLoader( Screen.class )
    86      private ScreenLoader screenLoader;
    87
    88      /**
    89       * Build the layout.  Also sets the ContentType and Locale headers
    90       * of the HttpServletResponse object.
    91       *
    92       *
    93       * @param pipelineData PipelineData
    94       * @throws Exception generic exception
    95       */
    96      @Override
    97      public void doBuild(PipelineData pipelineData)
    98          throws Exception
    99      {
    100         RunData data = getRunData(pipelineData);
    101         // Get the context needed by Velocity.
    102         Context context = velocityService.getContext(pipelineData);
    103
    104         String screenName = data.getScreen();
    105
    106         log.debug("Loading Screen " + screenName);
    107
    108         // First, generate the screen and put it in the context so
    109         // we can grab it the layout template.
    110         String results = screenLoader.eval(pipelineData, screenName);
    111         String returnValue = StringUtils.defaultIfEmpty(results, StringUtils.EMPTY);
    112
    113         // variable for the screen in the layout template
    114         context.put(TurbineConstants.SCREEN_PLACEHOLDER, returnValue);
    115
    116         // variable to reference the navigation screen in the layout template
    117         context.put(TurbineConstants.NAVIGATION_PLACEHOLDER,
    118                     new TemplateNavigation(data));
    119
    120         // Grab the layout template set in the VelocityPage.
    121         // If null, then use the default layout template
    122         // (done by the TemplateInfo object)
    123         String templateName = data.getTemplateInfo().getLayoutTemplate();
    124
    125         // Set the locale and content type
    126         data.getResponse().setLocale(data.getLocale());
    127         data.getResponse().setContentType(data.getContentType());
    128
    129         log.debug("Now trying to render layout " + templateName);
    130
    131         // Finally, generate the layout template and send it to the browser
    132         velocityService.handleRequest(context,
    133                 prefix + templateName, data.getResponse().getOutputStream());
    134     }
    135 }