netty的自定义Handler中使用SpringUtil.getBean获取Bean为null

用netty做聊天的时候，Handler里面看别人这么写能拿到Bean，我获取到的为null

UserService userService = (UserService)SpringUtil.getBean("userServiceImpl");

SpringUtil

public class SpringUtil implements ApplicationContextAware {
	
	private static ApplicationContext applicationContext;

	@Override
	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
		if (SpringUtil.applicationContext == null) {
			SpringUtil.applicationContext = applicationContext;
		}
	}

	// 获取applicationContext
	public static ApplicationContext getApplicationContext() {
		return applicationContext;
	}

	// 通过name获取 Bean.
	public static Object getBean(String name) {
		return getApplicationContext().getBean(name);
	}

	// 通过class获取Bean.
	public static <T> T getBean(Class<T> clazz) {
		return getApplicationContext().getBean(clazz);
	}

	// 通过name,以及Clazz返回指定的Bean
	public static <T> T getBean(String name, Class<T> clazz) {
		return getApplicationContext().getBean(name, clazz);
	}
}

别人这么写能拿到Bean，我获取到的为null
想了个办法，在启动类中定义一个ConfigurableApplicationContext 接受run方法的返回值，作为一个全局的context
这样就可以在netty的自定义Handler里使用了

public class Application {
    public static ConfigurableApplicationContext context = null;
    
    public static void main(String[] args) {
        context = SpringApplication.run(Application.class, args);
    }
}

在自定义Handler中这么写

    private static UserService userService;

    // spring容器上下文对象
    static {
        ConfigurableApplicationContext context = Application.context;
        userService = (UserService) context.getBean("userServiceImpl");
    }

就可以使用userService了