src/java/org/apache/turbine/modules/actions/VelocityAction.java

package org.apache.turbine.modules.actions;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache Turbine" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
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 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache Turbine", nor may "Apache" appear in their name, without
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 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import org.apache.turbine.modules.screens.TemplateScreen;
import org.apache.turbine.pipeline.PipelineData;
import org.apache.turbine.services.velocity.TurbineVelocity;
import org.apache.turbine.util.RunData;
import org.apache.turbine.util.velocity.VelocityActionEvent;
import org.apache.velocity.context.Context;

/**
 * This class provides a convenience methods for Velocity Actions
 * to use. Since this class is abstract, it should only be extended
 * and not used directly.
 *
 * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
 * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
 * @version $Id$
 */
public abstract class VelocityAction extends VelocityActionEvent
{
  /**
   * You SHOULD NOT override this method and implement it in your
   * action.
   * @deprecated Use PipelineData version instead.
   * @param data Turbine information.
   * @throws Exception a generic exception.
   */
  public void doPerform(RunData data)
      throws Exception
  {
    doPerform(data, getContext(data));
  }

  /**
   * You SHOULD NOT override this method and implement it in your
   * action.
   *
   * @param data Turbine information.
   * @throws Exception a generic exception.
   */
  public void doPerform(PipelineData pipelineData)
      throws Exception
  {
      doPerform(pipelineData, getContext(pipelineData));
  }

  
  /**
   * Initialize the module.
   * 
   * @throws Exception a generic exception.
   */
    public void initialize()
        throws Exception
    {
        initialized = true;
    }

  /**
   * You SHOULD override this method and implement it in your
   * action.
   * @deprecated Use PipelineData version instead.
   * @param data Turbine information.
   * @param context Context for web pages.
   * @throws Exception a generic exception.
   */
  public abstract void doPerform(RunData data,
                   Context context)
      throws Exception;

  /**
   * You SHOULD override this method and implement it in your
   * action.
   * 
   * This should become abstract when the RunData version is 
   * removed. For compatibility reasons this method will default
   * to using the RunData method unles it is overidden, which it
   * should be.
   * 
   * @param data Turbine information.
   * @param context Context for web pages.
   * @throws Exception a generic exception.
   */
  public void doPerform(PipelineData pipelineData,
                   Context context)
      throws Exception
  {
      RunData data = (RunData) getRunData(pipelineData);
      doPerform(data, context);
  }

  
  /**
   * Sets up the context and then calls super.perform(); thus,
   * subclasses don't have to worry about getting a context
   * themselves!  If a subclass throws an exception then depending
   * on whether action.event.bubbleexception is true, then it bubbles
   * it farther up, or traps it there.
   *
   * @deprecated Use PipelineData version instead.
   * @param data Turbine information.
   * @throws Exception a generic exception.
   */
  protected void perform(RunData data)
      throws Exception
  {
    try {
      super.perform(data);
    }
    catch (Exception e){
      if(bubbleUpException){
      throw e;
      }

    }
  }

  /**
   * Sets up the context and then calls super.perform(); thus,
   * subclasses don't have to worry about getting a context
   * themselves!  If a subclass throws an exception then depending
   * on whether action.event.bubbleexception is true, then it bubbles
   * it farther up, or traps it there.
   *
   * @param data Turbine information.
   * @throws Exception a generic exception.
   */
  protected void perform(PipelineData pipelineData)
      throws Exception
  {
    try {
      super.perform(pipelineData);
    }
    catch (Exception e){
      if(bubbleUpException){
      throw e;
      }

    }
  }

  
  
  /**
   * This method is used when you want to short circuit an Action
   * and change the template that will be executed next.
   *
   * @deprecated Use PipelineData version instead.
   * @param data Turbine information.
   * @param template The template that will be executed next.
   */
  public void setTemplate(RunData data,
              String template)
  {
    TemplateScreen.setTemplate(data, template);
  }

  /**
   * This method is used when you want to short circuit an Action
   * and change the template that will be executed next.
   *
   * @param data Turbine information.
   * @param template The template that will be executed next.
   */
  public void setTemplate(PipelineData pipelineData,
              String template)
  {
      TemplateScreen.setTemplate(pipelineData, template);
  }

  
  
  /**
   * Return the Context needed by Velocity.
   *
   * @deprecated Use PipelineData version instead.
   * @param data Turbine information.
   * @return Context, a context for web pages.
   */
  protected Context getContext(RunData data)
  {
    return TurbineVelocity.getContext(data);
  }
  
  /**
   * Return the Context needed by Velocity.
   *
   * @param data Turbine information.
   * @return Context, a context for web pages.
   */
  protected Context getContext(PipelineData pipelineData)
  {
      return TurbineVelocity.getContext(pipelineData);
  }

}