1.表单用get方式提交
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="/WEB24/encodingServlet" method="get">
<input type="text" name="username">
<input type="submit" value="提交">
</form>
</body>
</html>
2.创建一个servlet用于获取表单数据 并输出
package com.cc.servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class EncodingServlet
*/
@WebServlet("/encodingServlet")
public class EncodingServlet extends HttpServlet {
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String parameter = request.getParameter("username");
System.out.println(parameter);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
3.创建过滤器，并增强request对象解决乱码
package com.cc.filter;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
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 javax.servlet.http.HttpServletRequestWrapper;
public class EncodingFilter implements Filter{
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
// TODO Auto-generated method stub
//request.setCharacterEncoding("UTF-8");
//被增强的对象
HttpServletRequest req = (HttpServletRequest) request;
EnhanceRequest enhanceRequest = new EnhanceRequest(req);
chain.doFilter(enhanceRequest, response);
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
// TODO Auto-generated method stub
}
@Override
public void destroy() {
// TODO Auto-generated method stub
}
class EnhanceRequest extends HttpServletRequestWrapper{
private HttpServletRequest request;
public EnhanceRequest(HttpServletRequest request){
super(request);
this.request=request;
}
//对getParameter增强
public String getParameter(String name){
String parameter=request.getParameter(name);//乱码
try {
parameter=new String(parameter.getBytes("iso8859-1"),"UTF-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return parameter;
}
}
}
4.编写web.xml
<filter>
<filter-name>encodeFilter</filter-name>
<filter-class>cn.cc.filter.EncodingFilter </filter-class>
</filter>
<filter-mapping>
<filter-name>encodeFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
5.控制台分别输出 处理前和处理后的输出
