JSP+Servlet+tomcat6.0+mysql中查询英文正常，但是中文查不出结果也不报错

1、首先要检查tomcat-->conf-->server.xml中字符集要改为一致，比如：UTF-8

2、在servlet的doGet或service中要设置

request.setCharacterEncoding("UTF-8")

3、web.xml中设置servlet的初始化参数

 <servlet>
    <init-param>
       <param-name>encoding</param-name>
       <param-value>UTF-8</param-value>
    </init-param>
  </servlet>

4、jsp页面需要注意的是

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8" %>

 

按照以上四点检查完毕后如果还是不行，就要写过滤器了：

package jspServletConnnectionCommons;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class CharacterEncodingFilter implements Filter{
 
 private String encode;
 
 //初始化
 @Override
 public void init(FilterConfig filterConfig) throws ServletException {
  encode = filterConfig.getInitParameter("encode");
  
 }
 //执行过滤
 @Override
 public void doFilter(ServletRequest req, ServletResponse res,
   FilterChain filterChain) throws IOException, ServletException {
  req.setCharacterEncoding(encode);
  filterChain.doFilter(req, res);
 }
 //销毁
 @Override
 public void destroy() {
  encode = null;
 }

}

再在web.xml中配置filter如下：
<filter> 
   <filter-name>characterEncodingFilter</filter-name>    
   <filter-class>org.itfuture.examples.web.filter.CharacterEncodingFilter</filter-class>    
   <init-param>       
     <param-name>encode</param-name>       
     <param-value>UTF-8</param-value>    
   </init-param>
   <init-param>          
     <param-name>encoding</param-name>          
     <param-value>UTF-8</param-value>       
   </init-param>
</filter>
<filter-mapping>       
   <filter-name>characterEncodingFilter</filter-name>       
   <url-pattern>/*</url-pattern>  
</filter-mapping>