Source code: filters/RequestDumperFilter.java
1 /*
2 * Copyright 2004 The Apache Software Foundation
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17
18 package filters;
19
20
21 import java.io.IOException;
22 import java.io.PrintWriter;
23 import java.io.StringWriter;
24 import java.sql.Timestamp;
25 import java.util.Enumeration;
26 import java.util.Locale;
27 import javax.servlet.Filter;
28 import javax.servlet.FilterChain;
29 import javax.servlet.FilterConfig;
30 import javax.servlet.ServletContext;
31 import javax.servlet.ServletException;
32 import javax.servlet.ServletRequest;
33 import javax.servlet.ServletResponse;
34 import javax.servlet.http.Cookie;
35 import javax.servlet.http.HttpServletRequest;
36
37
38 /**
39 * Example filter that dumps interesting state information about a request
40 * to the associated servlet context log file, before allowing the servlet
41 * to process the request in the usual way. This can be installed as needed
42 * to assist in debugging problems.
43 *
44 * @author Craig McClanahan
45 * @version $Revision: 267129 $ $Date: 2004-03-18 11:40:35 -0500 (Thu, 18 Mar 2004) $
46 */
47
48 public final class RequestDumperFilter implements Filter {
49
50
51 // ----------------------------------------------------- Instance Variables
52
53
54 /**
55 * The filter configuration object we are associated with. If this value
56 * is null, this filter instance is not currently configured.
57 */
58 private FilterConfig filterConfig = null;
59
60
61 // --------------------------------------------------------- Public Methods
62
63
64 /**
65 * Take this filter out of service.
66 */
67 public void destroy() {
68
69 this.filterConfig = null;
70
71 }
72
73
74 /**
75 * Time the processing that is performed by all subsequent filters in the
76 * current filter stack, including the ultimately invoked servlet.
77 *
78 * @param request The servlet request we are processing
79 * @param result The servlet response we are creating
80 * @param chain The filter chain we are processing
81 *
82 * @exception IOException if an input/output error occurs
83 * @exception ServletException if a servlet error occurs
84 */
85 public void doFilter(ServletRequest request, ServletResponse response,
86 FilterChain chain)
87 throws IOException, ServletException {
88
89 if (filterConfig == null)
90 return;
91
92 // Render the generic servlet request properties
93 StringWriter sw = new StringWriter();
94 PrintWriter writer = new PrintWriter(sw);
95 writer.println("Request Received at " +
96 (new Timestamp(System.currentTimeMillis())));
97 writer.println(" characterEncoding=" + request.getCharacterEncoding());
98 writer.println(" contentLength=" + request.getContentLength());
99 writer.println(" contentType=" + request.getContentType());
100 writer.println(" locale=" + request.getLocale());
101 writer.print(" locales=");
102 Enumeration locales = request.getLocales();
103 boolean first = true;
104 while (locales.hasMoreElements()) {
105 Locale locale = (Locale) locales.nextElement();
106 if (first)
107 first = false;
108 else
109 writer.print(", ");
110 writer.print(locale.toString());
111 }
112 writer.println();
113 Enumeration names = request.getParameterNames();
114 while (names.hasMoreElements()) {
115 String name = (String) names.nextElement();
116 writer.print(" parameter=" + name + "=");
117 String values[] = request.getParameterValues(name);
118 for (int i = 0; i < values.length; i++) {
119 if (i > 0)
120 writer.print(", ");
121 writer.print(values[i]);
122 }
123 writer.println();
124 }
125 writer.println(" protocol=" + request.getProtocol());
126 writer.println(" remoteAddr=" + request.getRemoteAddr());
127 writer.println(" remoteHost=" + request.getRemoteHost());
128 writer.println(" scheme=" + request.getScheme());
129 writer.println(" serverName=" + request.getServerName());
130 writer.println(" serverPort=" + request.getServerPort());
131 writer.println(" isSecure=" + request.isSecure());
132
133 // Render the HTTP servlet request properties
134 if (request instanceof HttpServletRequest) {
135 writer.println("---------------------------------------------");
136 HttpServletRequest hrequest = (HttpServletRequest) request;
137 writer.println(" contextPath=" + hrequest.getContextPath());
138 Cookie cookies[] = hrequest.getCookies();
139 if (cookies == null)
140 cookies = new Cookie[0];
141 for (int i = 0; i < cookies.length; i++) {
142 writer.println(" cookie=" + cookies[i].getName() +
143 "=" + cookies[i].getValue());
144 }
145 names = hrequest.getHeaderNames();
146 while (names.hasMoreElements()) {
147 String name = (String) names.nextElement();
148 String value = hrequest.getHeader(name);
149 writer.println(" header=" + name + "=" + value);
150 }
151 writer.println(" method=" + hrequest.getMethod());
152 writer.println(" pathInfo=" + hrequest.getPathInfo());
153 writer.println(" queryString=" + hrequest.getQueryString());
154 writer.println(" remoteUser=" + hrequest.getRemoteUser());
155 writer.println("requestedSessionId=" +
156 hrequest.getRequestedSessionId());
157 writer.println(" requestURI=" + hrequest.getRequestURI());
158 writer.println(" servletPath=" + hrequest.getServletPath());
159 }
160 writer.println("=============================================");
161
162 // Log the resulting string
163 writer.flush();
164 filterConfig.getServletContext().log(sw.getBuffer().toString());
165
166 // Pass control on to the next filter
167 chain.doFilter(request, response);
168
169 }
170
171
172 /**
173 * Place this filter into service.
174 *
175 * @param filterConfig The filter configuration object
176 */
177 public void init(FilterConfig filterConfig) throws ServletException {
178
179 this.filterConfig = filterConfig;
180
181 }
182
183
184 /**
185 * Return a String representation of this object.
186 */
187 public String toString() {
188
189 if (filterConfig == null)
190 return ("RequestDumperFilter()");
191 StringBuffer sb = new StringBuffer("RequestDumperFilter(");
192 sb.append(filterConfig);
193 sb.append(")");
194 return (sb.toString());
195
196 }
197
198
199 }
200