@SuppressWarnings("unchecked")
	private void fillBeanMap(ConfigurationPropertiesBeans beans) {
		this.beanMap = new HashMap<>();
		Field field = ReflectionUtils.findField(beans.getClass(), "beans");
		if (field != null) {
			field.setAccessible(true);
			this.beanMap.putAll((Map<String, ConfigurationPropertiesBean>) Optional
					.ofNullable(ReflectionUtils.getField(field, beans))
					.orElse(Collections.emptyMap()));
		}
	}
Extend {@link ConfigurationPropertiesRebinder}.
<p>
Spring team doesn't seem to support single {@link ConfigurationPropertiesBean} refresh.
<p>
SmartConfigurationPropertiesRebinder can refresh specific
{@link ConfigurationPropertiesBean} base on the change keys.
<p>
<strong> NOTE: We still use Spring's default behavior (full refresh) as default
behavior, This feature can be considered an advanced feature, it may not be as stable
as the default behavior. </strong>

@author freeman
@since 2021.0.1.1
spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-nacos-config/src/main/java/com/alibaba/cloud/nacos/refresh/SmartConfigurationPropertiesRebinder.java