servlet 基础>创建Maven Web项目>实例

 

 

第一步:打开Idea软件

 

1>写一个类继承HttpServlet

 1 package com.werner.app.controller;
 2 
 3 import javax.servlet.ServletException;
 4 import javax.servlet.http.HttpServlet;
 5 import javax.servlet.http.HttpServletRequest;
 6 import javax.servlet.http.HttpServletResponse;
 7 import java.io.IOException;
 8 import java.io.PrintWriter;
 9 
10 /**
11  * Servlet开发基本步骤
12  * 1>写一个类继承HttpServlet
13  * 2>重写doGet或者doPost 方法
14  * 3>在web.xml中注册   注册Servlet
15  * 4>发布应用
16  */
17 public class FirstServlet extends HttpServlet {
18     /**
19      * key=value&
20      * @param req
21      * @param resp
22      * @throws ServletException
23      * @throws IOException
24      */
25     @Override
26     //1
27     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
28         String page = req.getParameter("page");//10
29         String size = req.getParameter("size");//20
30         //可以调数据库的内容
31         //去数据库查询到数据之后
32         //返回前端
33         String msg = "我想大声告诉你";
34         resp.setContentType("text/html;charset=utf-8");
35         PrintWriter writer = resp.getWriter();
36         writer.write(
37                 "<html lang=\"en\">\n" +
38                 "<head>\n" +
39                 "    <meta charset=\"UTF-8\">\n" +
40                 "    <title>Title</title>\n" +
41                 "</head>\n" +
42                 "<body>\n" +
43                 "<p>"+msg+"</p>\n" +
44                 "</body>\n" +
45                 "</html>");
46     }
47 
48 
49     @Override
50     protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
51         super.doPost(req, resp);
52     }
53 
54     @Override
55     protected void doPut(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
56         super.doPut(req, resp);
57     }
58 
59     @Override
60     protected void doDelete(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
61         super.doDelete(req, resp);
62     }
63 }

2>重写doGet或者doPost 方法(见上面代码)

3>在web.xml中注册 注册Servlet

<!DOCTYPE web-app PUBLIC
        "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
        "http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    <display-name>Archetype Created Web Application</display-name>
    <servlet>
        <servlet-name>first</servlet-name>
        <!--包名+类型-->
        <servlet-class>com.werner.app.controller.FirstServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>first</servlet-name>
        <url-pattern>/first</url-pattern>
    </servlet-mapping>
</web-app>

 

4>发布应用

 

 插录:

基本配置:

 

 

posted @ 2017-08-29 20:42  友情天  阅读(3230)  评论(0)  编辑  收藏  举报