首先我们创建过过滤器:

package com.gbx;

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 Zh_Filter implements Filter{

	public void destroy() {
		// TODO Auto-generated method stub
		System.out.println("destroy ...");
	}

	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		
		//设置内置对象的字符集
		request.setCharacterEncoding("gb2312");
		response.setCharacterEncoding("gb2312");
		//处理过滤
		chain.doFilter(request, response);
	}

	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub
		System.out.println("init .. ");
	}

}

  

然后再web.xml中配置过滤器:

<filter>
  	<filter-name>filter</filter-name>
  	<filter-class>com.gbx.Zh_Filter</filter-class>
  </filter>
  <filter-mapping>
  	<filter-name>filter</filter-name>
 	<url-pattern>/*</url-pattern>
  </filter-mapping>