JAVA过滤器

对于get请求和post请求全局过滤：

自己创建一个类，实现HttpServletRequestWrapper接口

package com.dh.deno;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.Principal;
import java.util.Enumeration;
import java.util.Locale;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletInputStream;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpSession;

public class FilterSetRequest extends
        HttpServletRequestWrapper {
    public FilterSetRequest(HttpServletRequest request){
        super(request);
    }
    @Override
    public String getParameter(String name){
        String value = super.getParameter(name);
        //判断是否是使用get请求
        if(getMethod().equalsIgnoreCase("GET")){
        try
        {
            value = new String(value.getBytes("iso-8859-1"),"utf-8");
        } catch (UnsupportedEncodingException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        }
        return value;
    }
}
在Filter类中使用自己定义的reqest

package com.dh.deno;

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;
import javax.servlet.http.HttpServletRequest;

import com.sun.net.httpserver.Filter.Chain;

import jdk.nashorn.internal.ir.RuntimeNode.Request;

public class MyFilter implements Filter {

public void destroy() {
        // TODO Auto-generated method stub

}

public void doFilter(ServletRequest request,
            ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        //掉包的request
        
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");
        
        FilterSetRequest req = new FilterSetRequest((HttpServletRequest)request);
        chain.doFilter(req, response);
    }

public void init(FilterConfig arg0)
            throws ServletException {
        
    }

}