方式一：實現ServletContextListener介面

      @Component
      public class SpringBootInitialization1 implements ServletContextListener {
            @Override
	    public void contextInitialized(ServletContextEvent sce) {
		System.out.println("方式一：實現ServletContextListener介面");
	    }
      }

方式二：方法上加註解@PostConstruct

      @Component
      public class SpringBootInitialization2 {
            @PostConstruct
            public static void init() {
		System.out.println("方式二：方法上加註解@PostConstruct");
            }

      }

方式三：實現ServletContextAware介面

@Component
public class SpringBootInitialization3 implements ServletContextAware {

	@Override
	public void setServletContext(ServletContext servletContext) {
		System.out.println("方式三：實現ServletContextAware介面");
	}

}
 

方式四：實現ApplicationListener介面

@Component
public class SpringBootInitialization4 implements ApplicationListener<ContextRefreshedEvent> {

	@Override
	public void onApplicationEvent(ContextRefreshedEvent event) {
		System.out.println("方式四：實現ApplicationListener<ContextRefreshedEvent>介面");
	}

}
 

方式五：實現ApplicationRunner介面

@Component
public class SpringBootInitialization5 implements ApplicationRunner {

	@Override
	public void run(ApplicationArguments args) throws Exception {
		System.out.println("方式五：實現ApplicationRunner介面");
	}

}

方式六：實現CommandLineRunner介面

@Component
public class SpringBootInitialization6 implements CommandLineRunner {

	@Override
	public void run(String... args) throws Exception {
		System.out.println("方式六：實現CommandLineRunner介面");

	}

}