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

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

@Component
public class SpringBootInitialization3 implements ServletContextAware {

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

@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");
    }
}

@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");
    }
}

轉載自：SpringBoot啟動時載入方法 - 王旌羽 - 部落格園 (cnblogs.com)