ServletContext对象的生命周期监听器

ServletContextListener 接口定义了 ServletContext 对象生命周期的 监听行为。 void contextInitialized(ServletContextEvent sce) ServletContext对象创建之后会触发该监听方法，并将ServletContext 对象传递到该方法中。

    @Override
    public void contextInitialized(ServletContextEvent sce) {
        System.out.println("ServletContextLifecycleListener contextInitialized");
    }

    @Override
    public void contextDestroyed(ServletContextEvent sce) {
        System.out.println("ServletContextLifecycleListener contextDestroyed");
    }

新建listener文件夹中的ServletContextLifecycleListener类

package com.syh.listener;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;

@WebListener
public class ServletContextLifecycleListener implements ServletContextListener {
    @Override
    public void contextInitialized(ServletContextEvent sce) {
        System.out.println("ServletContextLifecycleListener contextInitialized");
    }

    @Override
    public void contextDestroyed(ServletContextEvent sce) {
        System.out.println("ServletContextLifecycleListener contextDestroyed");
    }
}