JSP 中Servlet的自己实现
一 步骤
1、继承HttpServlet
2、重写doGet()或者doPost()方法
3、在web.xml中注册Servlet
二 HttpServlet类继承图
三 实例
1、创建MyFirstServletDemo web project.
2、编辑index.jsp
<%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"https://www.jb51.net/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="https://www.jb51.net/<%=basePath%>" > <title>My JSP 'index.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link type="text/css" href="https://www.jb51.net/styles.css" > --> </head> <body> <h1>第一个Servlet小例子</h1> <a href="https://www.jb51.net/servlet/HelloServlet" >Get方式请求HelloServlet</a> <form action="https://www.jb51.net/servlet/HelloServlet" method="post"> <input type="submit" value="Post方式请求HelloServlet"> </form> </body> </html>
3、编写HelloServlet
package servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; //继承于HttpServlet public class HelloServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub System.out.println("处理get（）请求..."); PrintWriter out = response.getWriter(); response.setContentType("text/html; charset=utf-8"); out.println("<strong>Hello Servlet!</strong><br>"); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("处理post（）请求..."); PrintWriter out = response.getWriter(); response.setContentType("text/html; charset=utf-8"); out.println("<strong>Hello Servlet!</strong><br>"); } }
4、编写web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://java.sun.com/xml/ns/javaee ";> <display-name></display-name> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <servlet> <servlet-name>HelloServlet</servlet-name> <servlet-class>servlet.HelloServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>HelloServlet</servlet-name> <url-pattern>/servlet/HelloServlet</url-pattern> </servlet-mapping> </web-app>
四 运行结果
