private Method extractFallbackMethod(String fallback, Class<?> fallbackClass) {
		return BlockClassRegistry.lookupFallback(fallbackClass, fallback);
	}
Interceptor using by SentinelRestTemplate.

@author <a href="mailto:fangjian0423@gmail.com">Jim</a>
spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-sentinel/src/main/java/com/alibaba/cloud/sentinel/custom/SentinelProtectInterceptor.java