1
/** *//**//*
2
* <p>Company: 凌科软件 www.elingke.com </p>
3 * @author liubaojun
4 * @version 1.0
5 * Created on 2004-11-29
6 * 来源于 elinkBSP 部分源代码
7
*/
8
package com.elink.control;
9
10import java.io.*;
11import java.util.*;
12import java.util.zip.*;
13import javax.servlet.*;
14import javax.servlet.http.*;
15//import com.elink.util.*;
16
17/** *//** *//** *//**
18 * @author liubj
19 */
20
21public class BusiFilter implements Filter
22
{
23 private FilterConfig config = null;
24 private HashMap expiresMap = null;
25 private String encoding = null;
26
27 public void init(FilterConfig filterConfig)
28
{
29 this.config = filterConfig;
30 this.encoding = config.getInitParameter("encoding");
31 if( encoding == null || encoding.length() == 0 )
32 {
33 encoding = "GBK";
34
}
35 expiresMap = new HashMap();
36 Enumeration names = config.getInitParameterNames();
37 while( names.hasMoreElements() )
38 {
39 String paramName = (String)names.nextElement();
40 if( !"encoding".equals(paramName) )
41 {
42 String paramValue = config.getInitParameter(paramName);
43 try
44 {
45 Integer expires = Integer.valueOf( config.getInitParameter(paramName) );
46 expiresMap.put(paramName, expires);
47 }
48 catch( Exception ex)
49 {
50 //LogUtil.logError( "Filter."+paramValue+"="+paramValue);
51 }
52 }
53 }
54 }
55
56 public void doFilter( ServletRequest request, ServletResponse response, FilterChain chain)
57 throws IOException, ServletException
58 {
59 // 汉字问题
60 HttpServletRequest httpRequest = (HttpServletRequest)request;
61 httpRequest.setCharacterEncoding( encoding );
62// chain.doFilter(request, response);
63
64 // 压缩传输
65 HttpServletResponse httpResponse = (HttpServletResponse)response;
66 String uri = httpRequest.getRequestURI();
67
68 String transferEncoding = getGZIPEncoding((HttpServletRequest)request);
69 if (transferEncoding == null)
70 {
71 setResponseHeader( httpResponse, uri, transferEncoding );
72 chain.doFilter(request, response);
73 }
74 else
75 {
76 if( uri.endsWith(".ctl") || uri.endsWith("busictrl") ) // 不处理的 URL
77 {
78 chain.doFilter(request, response);
79 }
80 else
81 {
82 setResponseHeader( httpResponse, uri, transferEncoding );
83 httpResponse.setHeader("Content-Encoding", transferEncoding);
84 GZIPEncodableResponse wrappedResponse = new GZIPEncodableResponse((HttpServletResponse)response);
85 chain.doFilter(request, wrappedResponse);
86 wrappedResponse.flush();
87 }
88 }
89 }
90
91 public void destroy()
92 {
93 }
94
95 private void setResponseHeader( HttpServletResponse response, String uri, String transferEncoding )
96 {
97 //LogUtil.logDebug( uri + ".Accept-Encoding: "+ transferEncoding);
98 String ext = null;
99 int dot = uri.lastIndexOf(".");
100 if( dot != -1 )
101 {
102 ext = uri.substring( dot+1 );
103 }
104 if( ext!= null && ext.length() > 0 )
105 {
106 Integer expires = (Integer)expiresMap.get(ext);
107 if( expires != null )
108 {
109 //LogUtil.logDebug( uri + ".Expires: "+ expires.intValue());
110 if( expires.intValue() > 0 )
111 {
112 response.setHeader("Cache-Control","max-age="+expires.intValue()); //HTTP 1.1
113 }
114 else
115 {
116 response.setHeader("Cache-Control","no-cache");
117 response.setHeader("Pragma","no-cache"); //HTTP 1.0
118 response.setDateHeader ("Expires", expires.intValue() );
119 }
120 }
121 }
122 }
123
124private static String getGZIPEncoding(HttpServletRequest request)
125 {
126 String acceptEncoding = request.getHeader("Accept-Encoding");
127 if (acceptEncoding == null)
128 return null;
129 acceptEncoding = acceptEncoding.toLowerCase();
130 if (acceptEncoding.indexOf("x-gzip") >= 0)
131 {
132 return "x-gzip";
133 }
134 if (acceptEncoding.indexOf("gzip") >= 0)
135 {
136 return "gzip";
137 }
138 return null;
139 }
140
141 private class GZIPEncodableResponse extends HttpServletResponseWrapper
142 {
143 private GZIPServletStream wrappedOut;
144
145 public GZIPEncodableResponse(HttpServletResponse response) throws IOException
146 {
147 super(response);
148 wrappedOut = new GZIPServletStream(response.getOutputStream());
149 }
150
151 public ServletOutputStream getOutputStream() throws IOException
152 {
153 return wrappedOut;
154 }
155
156 private PrintWriter wrappedWriter;
157
158 public PrintWriter getWriter() throws IOException
159 {
160 if (wrappedWriter == null)
161 {
162 wrappedWriter = new PrintWriter(new OutputStreamWriter(
163 getOutputStream(), getCharacterEncoding()));
164 }
165 return wrappedWriter;
166 }
167
168 public void flush() throws IOException
169 {
170 if (wrappedWriter != null)
171 {
172 wrappedWriter.flush();
173 }
174 wrappedOut.finish();
175 }
176 }
177
178 private class GZIPServletStream extends ServletOutputStream
179 {
180 private GZIPOutputStream outputStream;
181
182 public GZIPServletStream(OutputStream source) throws IOException
183 {
184 outputStream = new GZIPOutputStream(source);
185 }
186
187 public void finish() throws IOException
188 {
189 outputStream.finish();
190 }
191
192 public void write(byte[] buf) throws IOException
193 {
194 outputStream.write(buf);
195 }
196
197 public void write(byte[] buf, int off, int len) throws IOException
198 {
199 outputStream.write(buf, off, len);
200 }
201
202 public void write(int c) throws IOException
203 {
204 outputStream.write(c);
205 }
206
207 public void flush() throws IOException
208 {
209 outputStream.flush();
210 }
211
212 public void close() throws IOException
213 {
214 outputStream.close();
215 }
216 }
217} 配置文件
1<filter>
2 <filter-name>busifilter</filter-name>
3 <filter-class>com.elink.control.BusiFilter</filter-class>
4 <init-param>
5 <param-name>encoding</param-name>
6 <param-value>GBK</param-value>
7 </init-param>
8 <init-param>
9 <param-name>js</param-name>
10 <param-value>3600</param-value>
11 </init-param>
12 <init-param>
13 <param-name>gif</param-name>
14 <param-value>3600</param-value>
15 </init-param>
16 <init-param>
17 <param-name>jpg</param-name>
18 <param-value>3600</param-value>
19 </init-param>
20 <init-param>
21 <param-name>css</param-name>
22 <param-value>3600</param-value>
23 </init-param>
24 <init-param>
25 <param-name>bo</param-name>
26 <param-value>0</param-value>
27 </init-param>
28 <init-param>
29 <param-name>jsp</param-name>
30 <param-value>0</param-value>
31 </init-param>
32 </filter>
33 <filter-mapping>
34 <filter-name>busifilter</filter-name>
35 <url-pattern>/*</url-pattern>
36 </filter-mapping>
37
posted on 2007-01-05 13:59
公主她爹 阅读(510)
评论(0) 编辑 收藏 所属分类:
Servlet Filter