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jsp页面转发到servlet
一个简单的例子来了解一下jsp页面转发到servlet的过程，环境 eclipse、tomcat
1.工程目录结构如下
2.各部分代码如下
1>index.jsp
<%@ 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>首页</title></head><body> <a href = "http://www.mamicode.com/Forward">Forward</a></body></html>
2>web.xml
<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <servlet> <servlet-name>Forward</servlet-name> <servlet-class>com.scd.servlet.ForwardServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>Forward</servlet-name> <url-pattern>/Forward</url-pattern> </servlet-mapping></web-app>
3>ForwardServlet.java
package com.scd.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 ForwardServlet */@WebServlet("/ForwardServlet")public class ForwardServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public ForwardServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub System.out.println("My First Servlet!"); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub }}过程详解：当点击Forward连接时，请求到达服务器tomcat后，tomcat检查当前项目的web.xml中所有的<servlet-mapping></servlet-mapping>
配置中的<url-pattern></url-pattern>的属性值。看当中有没有一个和请求地址Forward相同。结果找到如，如下：
<servlet-mapping>
<servlet-name>Forward</servlet-name>
<url-pattern>/Forward</url-pattern>
</servlet-mapping>
其中 <url-pattern>/Forward</url-pattern> 是你访问地址
然后，tomcat找到和<servlet-mapping>相对应的<servlet-name>的<servlet>,根据<servlet-name>属性匹配, 找到了相同名字的<servlet-name>Forward</servlet>
如下：
<servlet>
<servlet-name>Forward</servlet-name>
<servlet-class>com.scd.servlet.ForwardServlet</servlet-
class>
</servlet>
根据上面的<servlet-class>找到Servlet文件ForwardServlet.java。
执行结果，在终端输出：
jsp页面转发到servlet