struts-sandbox/tiles-documentation/src/java/org/apache/struts/webapp/tiles/test/NoForward.java

/*
 * $Id$ 
 *
 * Copyright 1999-2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.struts.webapp.tiles.test;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.tiles.ComponentContext;


/**
 * Implementation of <strong>Action</strong> that create a TileContext in order
 * to force the TilesRequestProcessor to do an include instead of a forward.
 * The side effect is that request.getRequestURI will return the URL of the
 * calling struts action instead of the URL of the tiles layout.
 * See the jsp documentation to understand why.
 * Usage:
 * use this action in conjunction with an action declaration in struts config.
 * The action declaration should have one "success" forward to a Tile.
 * <pre>
 *   <action     path="/showRequestURI"
 *       		     type="org.apache.struts.webapp.tiles.test.NoForward">
 *    <forward  name="success"        path="test.action.noforward"/>
 *  </action>
 * </pre>
 * @version $Rev$ $Date$
 */

public final class NoForward extends Action {



    // --------------------------------------------------------- Public Methods


    /**
     *
     * @param mapping The ActionMapping used to select this instance
     * @param form The optional ActionForm bean for this request (if any)
     * @param request The HTTP request we are processing
     * @param response The HTTP response we are creating
     *
     * @exception Exception if the application business logic throws
     *  an exception
     * @since Struts 1.1
     */
    public ActionForward execute(ActionMapping mapping,
                                 ActionForm form,
                                 HttpServletRequest request,
                                 HttpServletResponse response)
        throws Exception {
      // Try to retrieve tile context
    ComponentContext context = ComponentContext.getContext( request );
    if( context == null )
      { // Not found, create a context
        // This context will be detected by the TilesRequestProcessor which will do an include
        // instead of a forward.
      ComponentContext tileContext = new ComponentContext( );
      ComponentContext.setContext( tileContext, request);
      }
	  return (mapping.findForward("success"));
    }


}