UML

UML类图几种关系的总结:http://www.uml.org.cn/oobject/201609062.asp

看懂UML类图和时序图:https://design-patterns.readthedocs.io/zh_CN/latest/read_uml.html

设计模式中类的关系:https://blog.youkuaiyun.com/zhengzhb/article/details/7187278

java_UML：继承/泛化、实现、依赖、关联、聚合、组合的联系与区别 （2016-07-12）:https://www.cnblogs.com/scevecn/p/5663369.html