java中文乱码问题

对于中文乱码问题，有时真的困惑我们很久，在我的实践中，我总结了一下

前提条件是要你配制好统一的编码格式 (utf-8,gbk,iso-8859-1);

1，如果当你提交请求是post 请求时，如果发现有乱码，你可以改用get请求，这样也能避免乱码

2， 当你从页面上面传的过来的参数少时，你可以在后台一个一个的处理，比如：

把从页面上传过来的字符串进行乱码处理
String userName=req.getParameter("userName");
String name=new String (userName.getBytes("ISO-8859-1"),"UTF-8");
  

3 ，你可以自己做一个小小的过滤器

package com.demo.struts;

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 FileFilter implements Filter{
   private FilterConfig config;
 public void destroy() {
  // TODO 自动生成方法存根
  
 }

 public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
  // TODO 自动生成方法存根
  System.out.println("进入到了过滤器");
  req.setCharacterEncoding("UTF-8");
  chain.doFilter(req,resp);
 }

 public void init(FilterConfig config) throws ServletException {
  this.config=config;
  // TODO 自动生成方法存根
  
 }

}

4， 你可以用“万能编码过滤器”(我自己取的，哈哈)

package filt;
import java.util.*;
import java.io.IOException;

import javax.servlet.*;
import javax.servlet.http.*;
public class EncodingFilter implements Filter{
 
 private FilterConfig filterConfig;
   //Handle the passed-in FilterConfig
   public void init(FilterConfig filterConfig) throws ServletException {
     this.filterConfig = filterConfig;
   }

   //Process the request/response pair
   public void doFilter(ServletRequest request, ServletResponse response,
                        FilterChain filterChain) {
     String encoding=filterConfig.getInitParameter("encoding");
       try {
           System.out.println("通过了字符编码过滤器");
           HttpServletRequest request1=(HttpServletRequest)request;

           if(request1.getMethod().equalsIgnoreCase("post")){
               System.out.println("通过了post请求过滤器");
               request.setCharacterEncoding(encoding);
           }else if(request1.getMethod().equalsIgnoreCase("get")){
               System.out.println("通过了get请求过滤器");
               Map map=request1.getParameterMap();
               Set set=map.keySet();
               Iterator it=set.iterator();
               while(it.hasNext()){
                   String key=(String)it.next();
                   Object value=map.get(key);
                   if(value instanceof String[]){
                      String[] values=(String[])value;
                      for (int i = 0; i < values.length; i++) {
                          values[i]=new String(values[i].getBytes("ISO-8859-1"),"GBK");
                      }
                   }
               }

           }
           filterChain.doFilter(request, response);
       } catch (ServletException sx) {
           filterConfig.getServletContext().log(sx.getMessage());
       } catch (IOException iox) {
           filterConfig.getServletContext().log(iox.getMessage());
       }

   }

   //Clean up resources
   public void destroy() {
   }
 }

你还要在web.xml里面配制一下