Guava
- http://ifeve.com/google-guava/
- [https://blog.csdn.net/anningzhu/article/details/77339048](https://blog.csdn.net/anningzhu/article/details/77339048)
- https://blog.csdn.net/qq_27093465/article/details/53212577
## ImmutableMap
http://ifeve.com/google-guava/