Spring Cloud Hystrix是基于Netflix Hystrix的封装，实现断路器，提供服务降级、容错保护，提供了超时机制、线程隔离等一系列服务保护功能。

Feign实现声明式服务调用，将REST服务包装成接口，效果类似本地调用一样

Spring Cloud Bus links nodes of a distributed system with a lightweight message broker. This can then be used to broadcast state changes (e.g. configuration changes) or other management instructions. The only implementation currently is with an AMQP broker as the transport, but the same basic feature set (and some more depending on the transport) is on the roadmap for other transports.

main主线程和自定义线程（Thread），自定义线程包括new Thread(Runnable target)和继承Thread

确认模式

延时加载（lazy loading）