servlet快速入门

servlet的概念请看官网：

*按照个人的理解servlet就是接口，依附在服务器上运行的一类接口。例如Tomcat服务器

servlet快速入门：

1、创建java类的接口

package com.yuan.servlet;
import javax.servlet.*;
import java.io.IOException;
//第一步
 public class servletDemo1 implements Servlet{

///添加重载的办法直接按ALT+enter快捷可获得
  @Override
    public void init(ServletConfig servletConfig) throws ServletException {

    }

    @Override
    public ServletConfig getServletConfig() {
        return null;
    }
//主方法
    @Override
    public void service(ServletRequest servletRequest, ServletResponse servletResponse) throws       ServletException, IOException {
        System.out.println("hello servlet");
    }

    @Override
    public String getServletInfo() {
        return null;
    }

    @Override
    public void destroy() {

    }
}

2、配置web.xml文件

*配置servlet 名字随便起
*配置包的路径：此包名字是我项目下的名字例如：com.yuan.servle.类名

<servlet-name>demo<\servlet-name>
<servlet-class>com.yuan.servle.servletDemo1<\servlet-class>

*配置访问的路径

<servlet-mapping>
        <servlet-name>demo1</servlet-name>
        <url-pattern>/demo1</url-pattern>
    </servlet-mapping>

配置

<?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">


<!-- 配置servlet -->
    <servlet>
        <servlet-name>demo1</servlet-name>
        <servlet-class>com.yuan.servlet.selectDemo1</servlet-class>
    </servlet>

<!--    配置路径    -->
    <servlet-mapping>
        <servlet-name>demo1</servlet-name>
        <url-pattern>/demo1</url-pattern>
    </servlet-mapping>
</web-app>