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1   /*
2    * $Id: ImageAction.java 471754 2006-11-06 14:55:09Z husted $
3    *
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *  http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  
23  package org.apache.struts.webapp.exercise;
24  
25  
26  import org.apache.struts.action.Action;
27  import org.apache.struts.action.ActionForm;
28  import org.apache.struts.action.ActionForward;
29  import org.apache.struts.action.ActionMapping;
30  
31  import javax.servlet.http.HttpServletRequest;
32  import javax.servlet.http.HttpServletResponse;
33  import java.io.InputStream;
34  import java.io.OutputStream;
35  
36  
37  /**
38   * Read image from resource given as ActionMapping parameter
39   * and copy to output stream.
40   *
41   * @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $
42   */
43  
44  public class ImageAction extends Action {
45  
46  
47      /**
48       * Read image from resource given as ActionMapping parameter
49       * and copy to output stream.
50       *
51       * @exception java.lang.Exception on input/output error
52       */
53      public ActionForward execute(
54              ActionMapping mapping,
55              ActionForm form,
56              HttpServletRequest request,
57              HttpServletResponse response)
58              throws Exception {
59  
60              // e.g. /$module/struts-power.gif
61              // :FIXME: Should compute module
62          String image = mapping.getParameter();
63  
64          byte[] buffer = new byte[2048];
65          int bytesRead;
66          InputStream input =
67                  getServlet().getServletContext().getResourceAsStream(image);
68          OutputStream
69                  out = response.getOutputStream();
70  
71          while ((bytesRead = input.read(buffer)) != -1) {
72              out.write(buffer, 0, bytesRead);
73          }
74          out.close();
75  
76          return null;
77      }
78  
79  }