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1 package com.genimen.djeneric.web;
2
3 import java.io.IOException  ;
4 import java.text.SimpleDateFormat ;
5 import java.util.Date ;
6 import java.util.Locale ;
7 import java.util.TimeZone ;
8
9 import javax.servlet.ServletContext ;
10 import javax.servlet.ServletException ;
11 import javax.servlet.http.HttpServletRequest ;
12 import javax.servlet.http.HttpServletResponse ;
13
14 import com.genimen.djeneric.repository.exceptions.DjenericException;
15 import com.genimen.djeneric.structure.ResourceDefinition;
16 import com.genimen.djeneric.web.controller.DjenericController;
17 import com.genimen.djeneric.web.util.DjenericServlet;
18 import com.genimen.djeneric.web.util.DjenericSessionManager;
19
20
24 public class ResourceServlet extends DjenericServlet
25 {
26 private static final long serialVersionUID = 1L;
27 public static final String HTTP_RESPONSE_DATE_HEADER = "EEE, dd MMM yyyy HH:mm:ss zzz";
28 private static SimpleDateFormat DATE_FORMAT;
29 long _lastmodified = System.currentTimeMillis();
30 private int _expirySeconds = 60 * 60 * 24;
31
32 public ResourceServlet()
33 {
34 DATE_FORMAT = new SimpleDateFormat (HTTP_RESPONSE_DATE_HEADER, Locale.US);
35 DATE_FORMAT.setTimeZone(TimeZone.getTimeZone("GMT"));
36 }
37
38 public long getLastModified(HttpServletRequest req)
39 {
40 return _lastmodified;
41 }
42
43 public void enableBrowserCaching(HttpServletResponse response)
44 {
45 response.setHeader("Cache-Control", "max-age=" + String.valueOf(_expirySeconds) + ", " + "s-max-age="
46 + String.valueOf(_expirySeconds)
47 + ", public, must-revalidate, proxy-revalidate");
48 response.setHeader("Expires", DATE_FORMAT.format(new Date (System.currentTimeMillis() + _expirySeconds * 1000)));
49 }
50
51 public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException
52 {
53 enableBrowserCaching(resp);
54 String fileName = req.getPathInfo().toString();
55
56 DjenericSessionManager mgr = (DjenericSessionManager) req.getSession()
57 .getAttribute(DjenericController.DJENERIC_SESSION_MANAGER);
58 ResourceDefinition res = null;
59 if (mgr != null)
60 {
61 try
62 {
63 res = mgr.getResource(fileName);
64 }
65 catch (DjenericException e)
66 {
67 throw new ServletException (e);
68 }
69 }
70
71 if (res == null)
72 {
73 resp.sendError(404);
74 }
75 else
76 {
77 resp.setContentType(getContentType(fileName));
78 resp.getOutputStream().write(res.getBytes());
79 }
80 }
81
82 private String getContentType(String fileName)
83 {
84 ServletContext sc = getServletContext();
85 String type = sc.getMimeType(fileName);
86 if (type == null) type = "text/plain";
87 return type;
88 }
89
90 } |
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