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1
23
24 package org.infoglue.deliver.applications.filters;
25
26 import java.io.IOException  ;
27 import java.net.URLDecoder ;
28 import java.util.ArrayList ;
29 import java.util.Enumeration ;
30 import java.util.List ;
31 import java.util.StringTokenizer ;
32
33 import javax.servlet.Filter ;
34 import javax.servlet.FilterChain ;
35 import javax.servlet.FilterConfig ;
36 import javax.servlet.ServletException ;
37 import javax.servlet.ServletRequest ;
38 import javax.servlet.ServletResponse ;
39 import javax.servlet.http.HttpServletRequest ;
40 import javax.servlet.http.HttpServletResponse ;
41
42 import org.apache.log4j.Logger;
43 import org.infoglue.deliver.util.CacheController;
44
45
50
51 public class CacheEvictionFilter implements Filter
52 {
53 public final static Logger logger = Logger.getLogger(CacheEvictionFilter.class.getName());
54
55 private static String FILTER_URIS_PARAMETER = "FilterURIs";
56
57 private FilterConfig filterConfig = null;
58 private URIMatcher uriMatcher = null;
59
60 public void init(FilterConfig filterConfig) throws ServletException
61 {
62 this.filterConfig = filterConfig;
63 String filterURIs = filterConfig.getInitParameter(FILTER_URIS_PARAMETER);
64 uriMatcher = URIMatcher.compilePatterns(splitString(filterURIs, ","), false);
65 }
66
67 public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException , ServletException
68 {
69 HttpServletRequest httpRequest = (HttpServletRequest ) servletRequest;
70 HttpServletResponse httpResponse = (HttpServletResponse ) servletResponse;
71
72 try
73 {
74 String requestURI = URLDecoder.decode(getContextRelativeURI(httpRequest), "UTF-8");
75 String userAgent = httpRequest.getHeader("user-agent");
76 if(userAgent != null)
77 userAgent = userAgent.toLowerCase();
78
79 if(logger.isInfoEnabled())
80 logger.info("userAgent:" + userAgent);
81
82 if (!uriMatcher.matches(requestURI) && userAgent != null && userAgent.indexOf("java") == -1 && userAgent.indexOf("axis") == -1)
83 {
84 CacheController.evictWaitingCache();
85 }
86 }
87 catch (Exception e)
88 {
89 logger.error("CacheEvictionFilter threw error:" + e.getMessage(), e);
90 }
91
92 filterChain.doFilter(httpRequest, httpResponse);
93 }
94
95 public void destroy()
96 {
97 }
98
99 private String getContextRelativeURI(HttpServletRequest request)
100 {
101 String requestURI = request.getRequestURI();
102 String contextPath = request.getContextPath();
103 if (contextPath != null && requestURI.length() > 0)
104 {
105 requestURI = requestURI.substring(contextPath.length(), requestURI.length());
106 }
107
108 if (requestURI.length() == 0)
109 return "/";
110
111 return requestURI;
112 }
113
114 private String [] splitString(String str, String delimiter)
115 {
116 List list = new ArrayList ();
117 StringTokenizer st = new StringTokenizer (str, delimiter);
118 while (st.hasMoreTokens())
119 {
120 String t = st.nextToken();
122 if (t.startsWith("_"))
123 {
124 break;
125 }
126 else
127 {
128 list.add(t.trim());
130 }
131 }
132 return (String []) list.toArray(new String [list.size()]);
133 }
134
135 } |
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