Encoding filter 编码过滤器

1、首先编写过滤器，实际上就是继承了filter接口的一个类，实现其中的init  doChain  和destroy方法

package com.util;

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 EncoderFilter implements Filter {

    @Override
    public void destroy() {
        // TODO Auto-generated method stub
        System.out.println("i defined filter destroy~~~~~~~~~~~~~~~~~~~~~~");
    }

    @Override
    public void doFilter(ServletRequest arg0, ServletResponse arg1,
            FilterChain arg2) throws IOException, ServletException {
        // TODO Auto-generated method stub
        arg0.setCharacterEncoding("UTF-8");
        System.out.println("the request encoding is " + arg0.getCharacterEncoding());
        System.out.println("enter myself filter~~~~~~~~~~~~~~~~~~~~~~" + new String(arg0.getParameter("men.name").getBytes(), "GBK"));
        arg2.doFilter(arg0, arg1);
    }

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

    

}

EncoderFilter.java