/*

  * Copyright 1999-2001,2004 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.commons.workflow.web;

 import java.util.EmptyStackException;

 import javax.servlet.ServletContext;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 import javax.servlet.http.HttpSession;

 import org.apache.commons.collections.ArrayStack;

 import org.apache.commons.workflow.Context;

 import org.apache.commons.workflow.Scope;

 import org.apache.commons.workflow.base.BaseContext;

 /**

  * <p><strong>WebContext</strong> is a specialized <code>Context</code>

  * implementation appropriate for web applications that run on top of a

  * Servlet 2.2 (or later) container.  It exposes the attributes associated

  * with requests, sessions, and the servlet context as <code>Scopes</code>

  * within the workflow management system.</p>

  *

  * @version $Revision: 155475 $ $Date: 2005-02-26 13:31:11 +0000 (Sat, 26 Feb 2005) $

  * @author Craig R. McClanahan

  */

 public class WebContext extends BaseContext {

     // ----------------------------------------------------- Manifest Constants

     /**

      * The scope identifier for the scope associated with the current

      * servlet request.

      */

     public static final int REQUEST_SCOPE = 2;

     /**

      * The scope name for the scope associated with the current

      * servlet request.

      */

     public static final String REQUEST_SCOPE_NAME = "request";

     /**

      * The scope identifier for the scope associated with the current

      * HTTP session.

      */

     public static final int SESSION_SCOPE = 4;

     /**

      * The scope name for the scope associated with the current

      * HTTP session.

      */

     public static final String SESSION_SCOPE_NAME = "session";

     /**

      * The scope identifier for the scope associated with the current

      * servlet context.

      */

     public static final int APPLICATION_SCOPE = 6;

     /**

      * The scope name for the scope associated with the current

      * servlet context.

      */

     public static final String APPLICATION_SCOPE_NAME = "application";

     // ------------------------------------------------------------- Properties

     /**

      * The HttpSession that provides our associated "session" scope.

      */

     protected HttpSession httpSession = null;

     public HttpSession getHttpSession() {

         return (this.httpSession);

     }

     public void setHttpSession(HttpSession httpSession) {

         this.httpSession = httpSession;

         Scope oldScope = getScope(SESSION_SCOPE);

         if ((oldScope != null) && (oldScope instanceof HttpSessionScope))

             ((HttpSessionScope) oldScope).setHttpSession(httpSession);

         else

             addScope(SESSION_SCOPE, SESSION_SCOPE_NAME,

                      new HttpSessionScope(httpSession));

     }

     /**

      * The ServletContext that provides our associated "application" scope.

      */

     protected ServletContext servletContext = null;

     public ServletContext getServletContext() {

         return (this.servletContext);

     }

     public void setServletContext(ServletContext servletContext) {

         this.servletContext = servletContext;

         Scope oldScope = getScope(APPLICATION_SCOPE);

         if ((oldScope != null) && (oldScope instanceof ServletContextScope))

             ((ServletContextScope) oldScope).setServletContext(servletContext);

         else

             addScope(APPLICATION_SCOPE, APPLICATION_SCOPE_NAME,

                      new ServletContextScope(servletContext));

     }

     /**

      * The ServletRequest that provides our associated "request" scope.

      */

     protected ServletRequest servletRequest = null;

     public ServletRequest getServletRequest() {

         return (this.servletRequest);

     }

     public void setServletRequest(ServletRequest servletRequest) {

         this.servletRequest = servletRequest;

         Scope oldScope = getScope(REQUEST_SCOPE);

         if ((oldScope != null) && (oldScope instanceof ServletRequestScope))

             ((ServletRequestScope) oldScope).setServletRequest(servletRequest);

         else

             addScope(REQUEST_SCOPE, REQUEST_SCOPE_NAME,

                      new ServletRequestScope(servletRequest));

         // FIXME - Consider exposing the cookies and headers from

         // a request as "read only" scopes

     }

     /**

      * The ServletResponse we should pass on to any request dispatcher

      * delegations.

      */

     protected ServletResponse servletResponse = null;

     public ServletResponse getServletResponse() {

         return (this.servletResponse);

     }

     public void setServletResponse(ServletResponse servletResponse) {

         this.servletResponse = servletResponse;

     }

 }