📝 Writing docs.

Author: crossoverJie

README.md

@@ -16,6 +16,11 @@ Java 知识点，继续完善中。
 ---- | --- | --- | ---| ---| ---| ---| ---| ---|---|---
 
 
+---
+📊: [常用集合](https://github.com/crossoverJie/Java-Interview/blob/master/README.md#%E5%B8%B8%E7%94%A8%E9%9B%86%E5%90%88)
+⚔️: [多线程](https://github.com/crossoverJie/Java-Interview/blob/master/README.md#java-%E5%A4%9A%E7%BA%BF%E7%A8%8B)
+🖥: [JVM](https://github.com/crossoverJie/Java-Interview/blob/master/README.md#jvm)
+---
 
 ### 常用集合
 - [ArrayList/Vector](https://github.com/crossoverJie/Java-Interview/blob/master/MD/ArrayList.md)