@Override
	public void postProcessMergedBeanDefinition(RootBeanDefinition beanDefinition,
			Class<?> beanType, String beanName) {
		// Fixes #3329: Support custom RestTemplate
		if (beanName == null || !RestTemplate.class.isAssignableFrom(beanType)) {
			return;
		}

		SentinelRestTemplate sentinelRestTemplate = this.getSentinelRestTemplateFromBeanDefinition(beanDefinition);
		if (sentinelRestTemplate != null) {
			// check class and method validation
			checkSentinelRestTemplate(sentinelRestTemplate, beanName);
			cache.put(beanName, sentinelRestTemplate);
		}
	}
PostProcessor handle @SentinelRestTemplate Annotation, add interceptor for
RestTemplate.

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