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1
24 package org.jresearch.gossip.filters.cache;
25
26 import java.io.File  ;
27 import java.io.FileInputStream ;
28 import java.io.FileOutputStream ;
29 import java.io.IOException ;
30 import java.io.StringWriter ;
31 import java.util.Calendar ;
32 import java.util.Enumeration ;
33 import java.util.Locale ;
34
35 import javax.servlet.Filter ;
36 import javax.servlet.FilterChain ;
37 import javax.servlet.FilterConfig ;
38 import javax.servlet.ServletContext ;
39 import javax.servlet.ServletException ;
40 import javax.servlet.ServletOutputStream ;
41 import javax.servlet.ServletRequest ;
42 import javax.servlet.ServletResponse ;
43 import javax.servlet.http.HttpServletRequest ;
44 import javax.servlet.http.HttpServletResponse ;
45
46 import org.jresearch.gossip.IConst;
47 import org.jresearch.gossip.beans.user.User;
48
49 public class CacheFilter implements Filter {
50
51 ServletContext sc;
52
53 FilterConfig fc;
54
55 long cacheTimeout = Long.MAX_VALUE;
56
57 public void doFilter(ServletRequest req, ServletResponse res,
58 FilterChain chain) throws IOException , ServletException {
59 HttpServletRequest request = (HttpServletRequest ) req;
60 HttpServletResponse response = (HttpServletResponse ) res;
61
62 String uri = request.getRequestURI();
64 if (uri == null || uri.equals("") || uri.equals("/")) {
65 chain.doFilter(request, response);
66 return;
67 }
68 String r = sc.getRealPath("");
70 String path = fc.getInitParameter(uri);
71 if (path != null && path.equals("nocache")) {
72 chain.doFilter(request, response);
73 return;
74 }
75 path = r + path;
76
77 String id = request.getRequestURI()
79 + request.getQueryString()
80 + "__"
81 + ((User) request.getSession().getAttribute(
82 IConst.SESSION.USER_KEY)).getName();
83 String localeSensitive = fc.getInitParameter("locale-sensitive");
85 if (localeSensitive != null) {
86 StringWriter ldata = new StringWriter ();
87 Enumeration locales = request.getLocales();
88 while (locales.hasMoreElements()) {
89 Locale locale = (Locale ) locales.nextElement();
90 ldata.write(locale.getISO3Language());
91 }
92 id = id + ldata.toString();
93 }
94 File tempDir = (File ) sc.getAttribute("javax.servlet.context.tempdir");
95
96 String temp = tempDir.getAbsolutePath();
98 System.out.println(temp);
99 File file = new File (temp + id);
100
101 if (path == null) {
103 path = sc.getRealPath(request.getRequestURI());
104 }
105 File current = new File (path);
106
107 try {
108 long now = Calendar.getInstance().getTimeInMillis();
109 if (!file.exists()
111 || (file.exists() && current.lastModified() > file
112 .lastModified())
113 || cacheTimeout < now - file.lastModified()) {
114 String name = file.getAbsolutePath();
115
116 name = name.substring(0,
117 name.lastIndexOf(File.separatorChar) == -1 ? 0 : name
118 .lastIndexOf(File.separatorChar));
119 new File (name).mkdirs();
120
121 FileOutputStream fos = new FileOutputStream (file);
122 CacheResponseWrapper wrappedResponse = new CacheResponseWrapper(
123 response, fos);
124 chain.doFilter(req, wrappedResponse);
125
126 fos.flush();
127 fos.close();
128 }
129 } catch (ServletException e) {
130 if (!file.exists()) {
131 throw new ServletException (e);
132 }
133 } catch (IOException e) {
134 if (!file.exists()) {
135 throw e;
136 }
137 }
138
139 FileInputStream fis = new FileInputStream (file);
140 String mt = sc.getMimeType(request.getRequestURI());
141 response.setContentType(mt);
142 ServletOutputStream sos = res.getOutputStream();
143 for (int i = fis.read(); i != -1; i = fis.read()) {
144 sos.write((byte) i);
145 }
146 }
147
148 public void init(FilterConfig filterConfig) {
149 this.fc = filterConfig;
150 String ct = fc.getInitParameter("cacheTimeout");
152 if (ct != null) {
153 cacheTimeout = 60 * 1000 * Long.parseLong(ct);
154 }
155 this.sc = filterConfig.getServletContext();
157 }
158
159 public void destroy() {
160 this.sc = null;
161 this.fc = null;
162 }
163 } |
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