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.servlet.filters.doubleclick;
24  
25  import com.liferay.portal.kernel.util.StringPool;
26  import com.liferay.util.servlet.filters.CacheResponse;
27  import com.liferay.util.servlet.filters.CacheResponseData;
28  import com.liferay.util.servlet.filters.CacheResponseUtil;
29  
30  import java.io.IOException;
31  import java.io.Serializable;
32  
33  import javax.servlet.FilterChain;
34  import javax.servlet.ServletException;
35  import javax.servlet.http.HttpServletRequest;
36  import javax.servlet.http.HttpServletResponse;
37  
38  /**
39   * <a href="DoubleClickController.java.html"><b><i>View Source</i></b></a>
40   *
41   * @author Olaf Fricke
42   * @author Brian Wing Shun Chan
43   *
44   */
45  public class DoubleClickController implements Serializable {
46  
47      public void control(
48              HttpServletRequest request, HttpServletResponse response,
49              FilterChain filterChain)
50          throws IOException, ServletException {
51  
52          boolean firstRequest = false;
53  
54          CacheResponse cacheResponse = null;
55  
56          synchronized (this) {
57              if (_cacheResponse == null) {
58                  firstRequest = true;
59  
60                  _cacheResponse = new CacheResponse(response, StringPool.UTF8);
61                  _throwable = null;
62              }
63  
64              cacheResponse = _cacheResponse;
65          }
66  
67          if (firstRequest) {
68              try {
69                  filterChain.doFilter(request, _cacheResponse);
70              }
71              catch (Throwable t) {
72                  _throwable = t;
73              }
74              finally {
75                  synchronized (this) {
76                      _cacheResponse = null;
77  
78                      notifyAll();
79                  }
80              }
81          }
82          else {
83              synchronized (this) {
84                  while (_cacheResponse != null) {
85                      try {
86                          wait();
87                      }
88                      catch (InterruptedException ie) {
89                          Thread.currentThread().interrupt();
90                      }
91                  }
92              }
93          }
94  
95          if (_throwable != null) {
96              try {
97                  throw _throwable;
98              }
99              catch (IOException ioe) {
100                 throw ioe;
101             }
102             catch (ServletException se) {
103                 throw se;
104             }
105             catch (RuntimeException re) {
106                 throw re;
107             }
108             catch (Error e) {
109                 throw e;
110             }
111             catch (Throwable t) {
112                 throw new RuntimeException(t);
113             }
114         }
115 
116         CacheResponseData data = new CacheResponseData(
117             cacheResponse.getData(), cacheResponse.getContentType(),
118             cacheResponse.getHeaders());
119 
120         CacheResponseUtil.write(response, data);
121     }
122 
123     private CacheResponse _cacheResponse;
124     private Throwable _throwable;
125 
126 }