标签:代码 extends link form ati app rate .com ...
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javaEE:7
javaSE:1.8
JSTL:1.2.2
server:tomcat 8.5
explorer:Firefox
os:windows7 x64
ide:MyEclipse 2017
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1"> <servlet> <servlet-name>myGenericServlet</servlet-name> <servlet-class>jizuiku.web.servlet.MyGenericServlet</servlet-class><!-- 执行的是这个类 --> <init-param> <param-name>minNum</param-name> <param-value>10</param-value> </init-param> <init-param> <param-name>maxNum</param-name> <param-value>100</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>myGenericServlet</servlet-name> <!-- 两个name 相应就好 --> <url-pattern>/MyGenericServletDemo</url-pattern><!-- 访问的是这个路径 --> </servlet-mapping> </web-app>
继承GenericServlet的类的代码
package jizuiku.web.servlet;
import java.io.IOException;
import javax.servlet.GenericServlet;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
/**
*
*
* @author 给最苦
* @version V17.10.20
*/
public class MyGenericServlet extends GenericServlet{
/**
*
*/
private static final long serialVersionUID = 1L;
@Override
public void service(ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException, IOException {
System.out.println("执行service()...");
}
// 根据源代码可以推出 ,要重写的方法一定是 init()
@Override
public void init() throws ServletException {
// TODO Auto-generated method stub
System.out.println("你好,执行初始化程序");
}
@Override
public void destroy() {
// TODO Auto-generated method stub
System.out.println("执行destroy()...");
}
}
效果
如上浏览器访问指定页面 一次,控制台输出信息发生如下变化

扩展
为什么要重写 无参数的init()方法?请看源代码
/**
* Called by the servlet container to indicate to a servlet that the servlet
* is being placed into service. See {@link Servlet#init}.
* <p>
* This implementation stores the {@link ServletConfig} object it receives
* from the servlet container for later use. When overriding this form of
* the method, call <code>super.init(config)</code>.
*
* @param config
* the <code>ServletConfig</code> object that contains
* configuration information for this servlet
* @exception ServletException
* if an exception occurs that interrupts the servlet‘s
* normal operation
* @see UnavailableException
*/
@Override
public void init(ServletConfig config) throws ServletException {
this.config = config;
this.init();
}
关于serialVersionUID的简单介绍
网址:http://www.cnblogs.com/btdxqz/p/6806372.html
学习资源:itcast和itheima视频库。如果您有公开的资源,可以分享给我的话,用您的资源学习也可以。
博文是观看视频后,融入思考写成的。博文好,是老师讲得好。博文坏,是 给最苦 没认真。
JavaWeb基础 继承GenericServlet 简单示例
标签:代码 extends link form ati app rate .com ...
原文地址:http://www.cnblogs.com/jizuiku/p/7707362.html