当初在设计WebLucene 的时候，为了能够正确的截取请求中的中文q参数，在执行request.getParameter("q")之前先调用了request.setCharacterEncoding("gb2312")方法。这样虽然避免了乱码问题的出现，但却使得WebLucene 同时只能对一种编码进行处理，无法实现类似于Google 的搜索效果，例如下面两个链接：
http://www.google.com/search?ie=UTF-8&q=%E5%8C%97%E4%BA%AC
http://www.google.com/search?ie=gb2312&q=%B1%B1%BE%A9

查找的都是关键字为“北京”的内容，只是前者的 Url 是以UTF-8 方式进行UrlEncode 得的，而后者则采用的是Gb2312。

在Google 上查找了很多关于setCharacterEncoding 和“多语言支持” 的文章，最后还是用最古老的方法解决了问题，见下面一段代码：
String ie = request.getParameter("encoding");

String q = new String(request.getParameter("q").getBytes("ISO-8859-1"), ie);
这样，只要$q 是以$encodig 方式进行提交/UrlEncode 的，那么我们就可以得到正确的q参数了——但有一点需要注意，就是要用 “ISO-8859-1” 的形式对字符串q 进行getBytes() 操作，而不能采用Utf-8的形式（至少我目前的试验结果是这样的）。

之所以不能用UTF-8 是因为一些应用服务器，如resin2.*，在试图用UTF-8 编码解析参数的时候，往往会因为参数中含有了不合法的UTF-8 字符而产生异常，从而导致无法正常的解析参数。

 

稍后请见详细描述。

大家可以用我后面的程序作一个试验：

首先把resin的缺省编码设为UTF-8：
<log id='/' href='stderr:' timestamp="[%H:%M:%S.%s]"/>

<web-app character-encoding='UTF-8'>
....
    <servlet>
        <servlet-name>character</servlet-name>
        <servlet-class>com.chedong.weblucene.CharacterEncodingTest</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>character</servlet-name>
        <url-pattern>/character</url-pattern>
    </servlet-mapping>
....
</web-app>

然后访问http://localhost:8080/weblucene/search?encoding=UTF-8&q=%E5%8C%97%E4%BA%AC，在resin 的log 中你会发现：
[19:10:52.484] java.io.CharConversionException: illegal utf8 encoding
        at com.caucho.vfs.i18n.UTF8Reader.read(UTF8Reader.java:102)
        at com.caucho.vfs.ByteToChar.readChar(ByteToChar.java:179)
        at com.caucho.vfs.ByteToChar.getConvertedString(ByteToChar.java:126)
        at com.caucho.server.http.Form.parseQueryString(Form.java:100)
        at com.caucho.server.http.Request.parseQuery(Request.java:1352)
        at com.caucho.server.http.Request.getParameterValues(Request.java:1449)
        at com.caucho.server.http.Request.getParameter(Request.java:1459)
        at com.chedong.weblucene.CharacterEncodingTest.doGet(Unknown Source)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:126)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:103)
        at com.caucho.server.http.FilterChainServlet.doFilter(FilterChainServlet.java:96)
        at com.caucho.server.http.Invocation.service(Invocation.java:315)
        at com.caucho.server.http.CacheInvocation.service(CacheInvocation.java:135)
        at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:246)
        at com.caucho.server.http.HttpRequest.handleConnection(HttpRequest.java:163)
        at com.caucho.server.TcpConnection.run(TcpConnection.java:139)
        at java.lang.Thread.run(Thread.java:536)

附：
1.测试程序

package com.chedong.weblucene;   import org.apache.log4j.Logger;   import java.io.IOException; import java.io.PrintWriter;   import java.util.Enumeration;   import javax.servlet.ServletConfig; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;   public class CharacterEncodingTest extends HttpServlet {     //~ Static fields/initializers ---------------------------------------------       /** The global logger, it will be configured when the servlet loaded */     private static Logger logger = Logger.getLogger(CharacterEncodingTest.class                                                     .getName()                                                    );       //~ Methods ----------------------------------------------------------------       public void destroy() {         super.destroy();     }       protected void doGet(HttpServletRequest request,                          HttpServletResponse response                         ) throws IOException, ServletException {           //request.setCharacterEncoding("ISO-8859-1");           response.setContentType("text/html;charset=utf-8");         PrintWriter out = response.getWriter();             out.println("");         out.println("");         out.println("");         out.println("");             out.println("");           System.out.println("i get a request, with encoding: " + request.getCharacterEncoding() + " ");           String q = "empty";         if(request.getParameter("q") != null) {             String ie = request.getParameter("ie");             if(ie == null) {                 ie = "gb2312";             }             q = request.getParameter("q");             System.out.println("raw q:" + q + ".");             q = new String(q.getBytes("iso-8859-1"), ie);             System.out.println("parsed q with(" + ie + "):" + q);         } else {             q = "null";             Enumeration params = request.getParameterNames();             while(params.hasMoreElements()) {                 String param = (String) params.nextElement();                 System.out.println("param: " + param + "-" + request.getParameter(param) + ". ");             }         }         out.println(q);           out.println("");         out.println("");           /* flush the buffer */         out.flush();         out.close();     }       public void init(ServletConfig servletConfig) throws ServletException {         super.init(servletConfig);     } }