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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  
19  package filters;
20  
21  
22  import java.io.IOException;
23  import java.io.PrintWriter;
24  import java.io.StringWriter;
25  import java.sql.Timestamp;
26  import java.util.Enumeration;
27  import java.util.Locale;
28  import javax.servlet.Filter;
29  import javax.servlet.FilterChain;
30  import javax.servlet.FilterConfig;
31  import javax.servlet.ServletContext;
32  import javax.servlet.ServletException;
33  import javax.servlet.ServletRequest;
34  import javax.servlet.ServletResponse;
35  import javax.servlet.http.Cookie;
36  import javax.servlet.http.HttpServletRequest;
37  
38  
39  /**
40   * Example filter that dumps interesting state information about a request
41   * to the associated servlet context log file, before allowing the servlet
42   * to process the request in the usual way.  This can be installed as needed
43   * to assist in debugging problems.
44   *
45   * @author Craig McClanahan
46   * @version $Revision: 267129 $ $Date: 2004-03-18 08:40:35 -0800 (Thu, 18 Mar 2004) $
47   */
48  
49  public final class RequestDumperFilter implements Filter {
50  
51  
52      // ----------------------------------------------------- Instance Variables
53  
54  
55      /**
56       * The filter configuration object we are associated with.  If this value
57       * is null, this filter instance is not currently configured.
58       */
59      private FilterConfig filterConfig = null;
60  
61  
62      // --------------------------------------------------------- Public Methods
63  
64  
65      /**
66       * Take this filter out of service.
67       */
68      public void destroy() {
69  
70          this.filterConfig = null;
71  
72      }
73  
74  
75      /**
76       * Time the processing that is performed by all subsequent filters in the
77       * current filter stack, including the ultimately invoked servlet.
78       *
79       * @param request The servlet request we are processing
80       * @param result The servlet response we are creating
81       * @param chain The filter chain we are processing
82       *
83       * @exception IOException if an input/output error occurs
84       * @exception ServletException if a servlet error occurs
85       */
86      public void doFilter(ServletRequest request, ServletResponse response,
87                           FilterChain chain)
88  	throws IOException, ServletException {
89  
90          if (filterConfig == null)
91  	    return;
92  
93  	// Render the generic servlet request properties
94  	StringWriter sw = new StringWriter();
95  	PrintWriter writer = new PrintWriter(sw);
96  	writer.println("Request Received at " +
97  		       (new Timestamp(System.currentTimeMillis())));
98  	writer.println(" characterEncoding=" + request.getCharacterEncoding());
99  	writer.println("     contentLength=" + request.getContentLength());
100 	writer.println("       contentType=" + request.getContentType());
101 	writer.println("            locale=" + request.getLocale());
102 	writer.print("           locales=");
103 	Enumeration locales = request.getLocales();
104 	boolean first = true;
105 	while (locales.hasMoreElements()) {
106 	    Locale locale = (Locale) locales.nextElement();
107 	    if (first)
108 	        first = false;
109 	    else
110 	        writer.print(", ");
111 	    writer.print(locale.toString());
112 	}
113 	writer.println();
114 	Enumeration names = request.getParameterNames();
115 	while (names.hasMoreElements()) {
116 	    String name = (String) names.nextElement();
117 	    writer.print("         parameter=" + name + "=");
118 	    String values[] = request.getParameterValues(name);
119 	    for (int i = 0; i < values.length; i++) {
120 	        if (i > 0)
121 		    writer.print(", ");
122 		writer.print(values[i]);
123 	    }
124 	    writer.println();
125 	}
126 	writer.println("          protocol=" + request.getProtocol());
127 	writer.println("        remoteAddr=" + request.getRemoteAddr());
128 	writer.println("        remoteHost=" + request.getRemoteHost());
129 	writer.println("            scheme=" + request.getScheme());
130 	writer.println("        serverName=" + request.getServerName());
131 	writer.println("        serverPort=" + request.getServerPort());
132 	writer.println("          isSecure=" + request.isSecure());
133 
134 	// Render the HTTP servlet request properties
135 	if (request instanceof HttpServletRequest) {
136 	    writer.println("---------------------------------------------");
137 	    HttpServletRequest hrequest = (HttpServletRequest) request;
138 	    writer.println("       contextPath=" + hrequest.getContextPath());
139 	    Cookie cookies[] = hrequest.getCookies();
140             if (cookies == null)
141                 cookies = new Cookie[0];
142 	    for (int i = 0; i < cookies.length; i++) {
143 	        writer.println("            cookie=" + cookies[i].getName() +
144 			       "=" + cookies[i].getValue());
145 	    }
146 	    names = hrequest.getHeaderNames();
147 	    while (names.hasMoreElements()) {
148 	        String name = (String) names.nextElement();
149 		String value = hrequest.getHeader(name);
150 	        writer.println("            header=" + name + "=" + value);
151 	    }
152 	    writer.println("            method=" + hrequest.getMethod());
153 	    writer.println("          pathInfo=" + hrequest.getPathInfo());
154 	    writer.println("       queryString=" + hrequest.getQueryString());
155 	    writer.println("        remoteUser=" + hrequest.getRemoteUser());
156 	    writer.println("requestedSessionId=" +
157 			   hrequest.getRequestedSessionId());
158 	    writer.println("        requestURI=" + hrequest.getRequestURI());
159 	    writer.println("       servletPath=" + hrequest.getServletPath());
160 	}
161 	writer.println("=============================================");
162 
163 	// Log the resulting string
164 	writer.flush();
165 	filterConfig.getServletContext().log(sw.getBuffer().toString());
166 
167 	// Pass control on to the next filter
168         chain.doFilter(request, response);
169 
170     }
171 
172 
173     /**
174      * Place this filter into service.
175      *
176      * @param filterConfig The filter configuration object
177      */
178     public void init(FilterConfig filterConfig) throws ServletException {
179 
180 	this.filterConfig = filterConfig;
181 
182     }
183 
184 
185     /**
186      * Return a String representation of this object.
187      */
188     public String toString() {
189 
190 	if (filterConfig == null)
191 	    return ("RequestDumperFilter()");
192 	StringBuffer sb = new StringBuffer("RequestDumperFilter(");
193 	sb.append(filterConfig);
194 	sb.append(")");
195 	return (sb.toString());
196 
197     }
198 
199 
200 }
201