Servlet的生命周期

Servlet的生命周期

从第一次调用，到服务器关闭。如果在 web.xml 中配置了 load-on-startup 则是从服务器开启到服务器关闭。

代码示例：

package com.zxw.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class ServletLife extends HttpServlet {

//初始化方法，在servlet第一次加载内容的时候被调用

@Override

public void init() throws ServletException {

System.out.println("servlet初始化完成");

}

// service方法，真正处理请求的方法

@Override

protected void service(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

resp.getWriter().write("servlet life");

System.out.println("servlet life");

}

private void destory() {

System.out.println("我被销毁了...");

}

}

Web.xml配置

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="3.0"

    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/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">



  <servlet>

    <description>This is the description of my J2EE component</description>

    <display-name>This is the display name of my J2EE component</display-name>

    <servlet-name>ServletLife</servlet-name>

    <servlet-class>com.zxw.servlet.ServletLife</servlet-class>

  </servlet>

  <servlet>

    <description>This is the description of my J2EE component</description>

    <display-name>This is the display name of my J2EE component</display-name>

    <servlet-name>ServletMethod</servlet-name>

    <servlet-class>com.zxw.servlet.ServletMethod</servlet-class>

  </servlet>

  <servlet-mapping>

    <servlet-name>ServletLife</servlet-name>

    <url-pattern>/life</url-pattern>

  </servlet-mapping>

  <servlet-mapping>

    <servlet-name>ServletMethod</servlet-name>

    <url-pattern>/method</url-pattern>

  </servlet-mapping>

</web-app>

控制台效果

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浏览器效果

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