过滤器配置详解
* 拦截路径配置：
1. 具体资源路径： /index.jsp 只有访问index.jsp资源时，过滤器才会被执行
2. 拦截目录： /user/* 访问/user下的所有资源时，过滤器都会被执行
3. 后缀名拦截： *.jsp 访问所有后缀名为jsp资源时，过滤器都会被执行
4. 拦截所有资源：/* 访问所有资源时，过滤器都会被执行
<%--Created by IntelliJ IDEA.User: leonDate: /11/24Time: 11:30To change this template use File | Settings | File Templates.--%><%@ page contentType="text/html;charset=UTF-8" language="java" %><html><head><title>$Title$</title></head><body>hello.jsp....</body></html>
package com.learn.web.filter;import javax.servlet.*;import javax.servlet.annotation.WebFilter;import java.io.IOException;//@WebFilter("/index.jsp") // 1. 具体资源路径： /index.jsp 只有访问index.jsp资源时，过滤器才会被执行//@WebFilter("/user/*") // 2. 拦截目录： /user/*访问/user下的所有资源时，过滤器都会被执行@WebFilter("*.jsp")public class FilterDemo4 implements Filter {@Overridepublic void init(FilterConfig filterConfig) throws ServletException {}@Overridepublic void doFilter(ServletRequest servletRequest, ServletResponse servletResponse,FilterChain filterChain) throws IOException, ServletException {System.out.println("filterDemo4....");filterChain.doFilter(servletRequest, servletResponse);}@Overridepublic void destroy() {}}
package com.learn.web.servlet;import javax.servlet.*;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;@WebServlet("/user/findAllServlet")public class ServletDemo1 extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {this.doPost(req,resp);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {System.out.println("findAllServlet...");}}
package com.learn.web.servlet;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;@WebServlet("/user/updateServlet")public class ServletDemo2 extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {this.doPost(req,resp);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {System.out.println("updateServlet...");}}
