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    1   package org.apache.turbine.pipeline;
    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 java.io.IOException;
    25
    26  import org.apache.turbine.TurbineConstants;
    27  import org.apache.turbine.annotation.TurbineConfiguration;
    28  import org.apache.turbine.annotation.TurbineLoader;
    29  import org.apache.turbine.annotation.TurbineService;
    30  import org.apache.turbine.modules.Page;
    31  import org.apache.turbine.modules.PageLoader;
    32  import org.apache.turbine.services.template.TemplateService;
    33  import org.apache.turbine.util.TurbineException;
    34
    35  /**
    36   * Implements the Page Generation portion of the "Turbine classic"
    37   * processing pipeline (from the Turbine 2.x series).
    38   *
    39   * @author <a href="mailto:epugh@opensourceConnections.com">Eric Pugh</a>
    40   * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
    41   * @version $Id: ExecutePageValve.java 1773378 2016-12-09 13:19:59Z tv $
    42   */
    43  public class ExecutePageValve
    44      extends AbstractValve
    45  {
    46      /** Injected service instance */
    47      @TurbineService
    48      private TemplateService templateService;
    49
    50      /** Injected loader instance */
    51      @TurbineLoader( Page.class )
    52      private PageLoader pageLoader;
    53
    54      @TurbineConfiguration( TurbineConstants.PAGE_DEFAULT_KEY )
    55      private String pageDefault = TurbineConstants.PAGE_DEFAULT_DEFAULT;
    56
    57      /**
    58       * @see org.apache.turbine.pipeline.Valve#invoke(PipelineData, ValveContext)
    59       */
    60      @Override
    61      public void invoke(PipelineData pipelineData, ValveContext context)
    62          throws IOException, TurbineException
    63      {
    64          try
    65          {
    66              executePage(pipelineData);
    67          }
    68          catch (Exception e)
    69          {
    70              throw new TurbineException(e);
    71          }
    72
    73          // Pass control to the next Valve in the Pipeline
    74          context.invokeNext(pipelineData);
    75      }
    76
    77      /**
    78       * execute the page generation.
    79       *
    80       * @param pipelineData The run-time data.
    81       *
    82       * @throws Exception if the page execution fails
    83       */
    84      protected void executePage(PipelineData pipelineData)
    85          throws Exception
    86      {
    87          // Start the execution phase. DefaultPage will execute the
    88          // appropriate action as well as get the Layout from the
    89          // Screen and then execute that. The Layout is then
    90          // responsible for executing the Navigation and Screen
    91          // modules.
    92          //
    93          // Note that by default, this cannot be overridden from
    94          // parameters passed in via post/query data. This is for
    95          // security purposes.  You should really never need more
    96          // than just the default page.  If you do, add logic to
    97          // DefaultPage to do what you want.
    98
    99          String defaultPage = (templateService == null)
    100         ? null : templateService.getDefaultPageName(pipelineData);
    101
    102         if (defaultPage == null)
    103         {
    104             /*
    105              * In this case none of the template services are running.
    106              * The application may be using ECS for views, or a
    107              * decendent of RawScreen is trying to produce output.
    108              * If there is a 'page.default' property in the TR.props
    109              * then use that, otherwise return DefaultPage which will
    110              * handle ECS view scenarios and RawScreen scenarios. The
    111              * app developer can still specify the 'page.default'
    112              * if they wish but the DefaultPage should work in
    113              * most cases.
    114              */
    115             defaultPage = pageDefault;
    116         }
    117
    118         pageLoader.exec(pipelineData, defaultPage);
    119     }
    120 }