1   /**
2    * Copyright (c) 2000-2008 Liferay, Inc. All rights reserved.
3    *
4    * Permission is hereby granted, free of charge, to any person obtaining a copy
5    * of this software and associated documentation files (the "Software"), to deal
6    * in the Software without restriction, including without limitation the rights
7    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8    * copies of the Software, and to permit persons to whom the Software is
9    * furnished to do so, subject to the following conditions:
10   *
11   * The above copyright notice and this permission notice shall be included in
12   * all copies or substantial portions of the Software.
13   *
14   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20   * SOFTWARE.
21   */
22  
23  package com.liferay.portal.kernel.servlet;
24  
25  import com.liferay.portal.kernel.util.StringPool;
26  
27  import java.io.IOException;
28  
29  import java.util.HashMap;
30  import java.util.Map;
31  
32  import javax.servlet.ServletException;
33  import javax.servlet.http.HttpServlet;
34  import javax.servlet.http.HttpServletRequest;
35  import javax.servlet.http.HttpServletResponse;
36  
37  /**
38   * <a href="PortalDelegatorServlet.java.html"><b><i>View Source</i></b></a>
39   *
40   * <p>
41   * See http://support.liferay.com/browse/LEP-2297.
42   * </p>
43   *
44   * @author Olaf Fricke
45   * @author Brian Wing Shun Chan
46   *
47   */
48  public class PortalDelegatorServlet extends HttpServlet {
49  
50      public static void addDelegate(String subContext, HttpServlet delegate) {
51          if (subContext == null) {
52              throw new IllegalArgumentException();
53          }
54  
55          if (delegate == null) {
56              throw new IllegalArgumentException();
57          }
58  
59          _delegates.put(subContext, delegate);
60      }
61  
62      public static void removeDelegate(String subContext) {
63          if (subContext == null) {
64              throw new IllegalArgumentException();
65          }
66  
67          _delegates.remove(subContext);
68      }
69  
70      public void service(
71              HttpServletRequest request, HttpServletResponse response)
72          throws IOException, ServletException {
73  
74          String uri = request.getPathInfo();
75  
76          if ((uri == null) || (uri.length() == 0)) {
77              throw new ServletException("Path information is not specified");
78          }
79  
80          String[] paths = uri.split(StringPool.SLASH);
81  
82          if (paths.length < 2) {
83              throw new ServletException("Path " + uri + " is invalid");
84          }
85  
86          HttpServlet delegate = _delegates.get(paths[1]);
87  
88          if (delegate == null) {
89              throw new ServletException(
90                  "No servlet registred for context " + paths[1]);
91          }
92  
93          ClassLoader contextClassLoader =
94              Thread.currentThread().getContextClassLoader();
95  
96          try {
97              ClassLoader delegateClassLoader =
98                  delegate.getClass().getClassLoader();
99  
100             Thread.currentThread().setContextClassLoader(delegateClassLoader);
101 
102             delegate.service(request, response);
103         }
104         finally {
105             Thread.currentThread().setContextClassLoader(contextClassLoader);
106         }
107     }
108 
109     private static Map<String, HttpServlet> _delegates =
110         new HashMap<String, HttpServlet>();
111 
112 }