JSP 中Servlet的自己实现

作者：袖梨 2023-09-01

这篇文章主要介绍了JSP 中Servlet的自己实现的相关资料,希望通过本文能帮助到大家，让大家手动实现Servlet，需要的朋友可以参考下

JSP 中Servlet的自己实现

一步骤

1、继承HttpServlet2、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+"/";%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <base href="<%=basePath%>" rel="external nofollow" ><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 rel="stylesheet" type="text/css" href="styles.css" rel="external nofollow" >--> </head><body> <h1>第一个Servlet小例子</h1> <a href="servlet/HelloServlet" rel="external nofollow" >Get方式请求HelloServlet</a> <form action="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HttpServletpublic class HelloServlet extends HttpServlet { @Overrideprotected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {// TODO Auto-generated method stubSystem.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>");} @Overrideprotected 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/javaeehttp://java.sun.com/xml/ns/javaee/web-app_2_5.xsd";> <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