1）htmlcode：
<html>
<head>
<title>$Title$</title>
</head>
<body>
<form action="/login" method="post" >
姓名：<input type="text" name="username"><br>
备注：<textarea></textarea>
<input type="submit"><br>
</form>
</body>
</html>
2）servlet code
1 package jd.com.coding;
2
3 import javax.servlet.ServletException;
4 import javax.servlet.annotation.WebServlet;
5 import javax.servlet.http.HttpServlet;
6 import javax.servlet.http.HttpServletRequest;
7 import javax.servlet.http.HttpServletResponse;
8 import java.io.IOException;
9
10 @WebServlet(name = "Servletlogin" ,urlPatterns ="/login")
11 public class Servletlogin extends HttpServlet {
12 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
13 String username=request.getParameter("username");
14 System.out.println(username);
15
16
17
18 }
19
20 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
21
22 }
23 }
3）filter代码：
1 package jd.com.coding;
2
3 import javax.servlet.*;
4 import javax.servlet.annotation.WebFilter;
5 import javax.servlet.http.HttpServletRequest;
6 import javax.servlet.http.HttpServletResponse;
7 import java.io.IOException;
8 import java.lang.reflect.InvocationHandler;
9 import java.lang.reflect.Method;
10 import java.lang.reflect.Proxy;
11
12 @WebFilter(filterName = "FilterCoding",urlPatterns = "/login")
13 public class FilterCoding implements Filter {
14 public void destroy() {
15 }
16
17 public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException {
18 //增强
19 HttpServletResponse response= (HttpServletResponse) resp;
20 HttpServletRequest request= (HttpServletRequest) req;
21
22 HttpServletRequest reqproxy =(HttpServletRequest) Proxy.newProxyInstance(HttpServletRequest.class.getClassLoader(), (Class<?>[]) request.getClass().getGenericInterfaces(), new InvocationHandler() {
23 @Override
24 public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
25 if(method.getName().equalsIgnoreCase("getParameter")){
26 if(request.getMethod().equalsIgnoreCase("get")){
27 // String[get] ar=(String[]) args;
28 // String str=request.getParameter(ar[0]);
29 String str= (String) method.invoke(request,args);
30 return new String(str.getBytes("iso8859-1"),"utf-8");
31 }else if(request.getMethod().equalsIgnoreCase("post")){
32 request.setCharacterEncoding("utf-8");
33 return method.invoke(request,args);
34 }
35 }
36
37 return method.invoke(request,args);
38 }
39 });
40 chain.doFilter(reqproxy, resp);
41 }
42
43 public void init(FilterConfig config) throws ServletException {
44
45 }
46
47 }
其中获取类的接口集合使用Class类的方法：getClassLoader()
public Type[] getGenericInterfaces()
然后强转即可。
原文地址：https://www.cnblogs.com/evilliu/p/8728639.html
时间： 2024-10-13 10:25:56