<?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"><display-name>servlet_demo03</display-name><!-- 配置上下文参数 --><context-param><param-name>version</param-name><param-value>Version 1.0</param-value></context-param><servlet><servlet-name>servletContext</servlet-name><servlet-class>servlet_demo03.Servlet_Context</servlet-class></servlet><servlet-mapping><servlet-name>servletContext</servlet-name><url-pattern>/context.do</url-pattern></servlet-mapping><servlet><servlet-name>servletContext02</servlet-name><servlet-class>servlet_demo03.Servlet_Context02</servlet-class></servlet><servlet-mapping><servlet-name>servletContext02</servlet-name><url-pattern>/context02.do</url-pattern></servlet-mapping><welcome-file-list><welcome-file>index.html</welcome-file><welcome-file>index.htm</welcome-file><welcome-file>index.jsp</welcome-file><welcome-file>default.html</welcome-file><welcome-file>default.htm</welcome-file><welcome-file>default.jsp</welcome-file></welcome-file-list>
</web-app>

package servlet_demo03;import java.io.IOException;
import java.io.PrintWriter;import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class Servlet_Context extends HttpServlet {/*** */private static final long serialVersionUID = -4997823504444105170L;@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {// TODO Auto-generated method stubdoPost(req, resp);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {//获取上下文对象ServletContext sc=this.getServletContext();PrintWriter out=resp.getWriter();out.print(sc.getInitParameter("version"));}}

package servlet_demo03;import java.io.IOException;
import java.io.PrintWriter;import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class Servlet_Context02 extends HttpServlet {/*** */private static final long serialVersionUID = 7562320935883704783L;@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {// TODO Auto-generated method stubdoPost(req, resp);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {ServletContext sc=this.getServletContext();PrintWriter out=resp.getWriter();out.print(sc.getInitParameter("version"));}}