编写入门案例

1)编写java类,继承HttpServlet类

2)重新doGet和doPost方法

3)Servlet程序交给tomcat服务器运行!!

3.1 servlet程序的class码拷贝到WEB-INF/classes目录

3.2 在web.xml文件中进行配置

package com.loaderman.demo;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException; public class TestServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse response) throws ServletException, IOException {
//向浏览器输出内容
response.getWriter().write("this is first servlet!");
} @Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doGet(req, resp);
}
}

<?xml version="1.0" encoding="UTF-8"?>
<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_4_0.xsd"
version="4.0">
<!-- servlet的配置 -->
<servlet>
<!-- servlet的内部名称,自定义。尽量有意义 -->
<servlet-name>mTestServlet</servlet-name>
<!-- servlet的类全名: 包名+简单类名 -->
<servlet-class>com.loaderman.demo.TestServlet</servlet-class>
</servlet> <!-- servlet的映射配置 -->
<servlet-mapping>
<!-- servlet的内部名称,一定要和上面的内部名称保持一致!! -->
<servlet-name>mTestServlet</servlet-name>
<!-- servlet的映射路径(访问servlet的名称) -->
<url-pattern>/demotest</url-pattern>
</servlet-mapping>
</web-app>
05-08 08:04