3.Listener

1、MyServletContextListener 实现（implements） ServletContextListener 创建监听器。

package com.wzy.springbootweb02.servlet;
import lombok.extern.slf4j.Slf4j;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;
@Slf4j
@WebListener
public class MyServletContextListener implements ServletContextListener {
    @Override
    public void contextInitialized(ServletContextEvent sce) {
        log.info("MyServletContextLister监听到项目初始化完成。");
    }
    @Override
    public void contextDestroyed(ServletContextEvent sce) {
        log.info("MyServletContextLister监听到项目销毁。");
    }
}

2、在启动类上面加上扫描注解 @ServletComponentScan``(basePackages = ``"com.wzy.springbootweb02.servlet"``) 扫描Servlet程序。

package com.wzy.springbootweb02;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;
@ServletComponentScan(basePackages = "com.wzy.springbootweb02.servlet")
@SpringBootApplication
public class SpringbootWeb02Application {
    public static void main(String[] args) {
        SpringApplication.run(SpringbootWeb02Application.class, args);
    }
}