📝 Writing docs.

Author: crossoverJie

README.md

@@ -11,7 +11,11 @@ tags:
 ---
 
 
-
+---
+📊: [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)
+---
 
 
 [![Build Status](https://travis-ci.org/crossoverJie/Java-Interview.svg?branch=master)](https://travis-ci.org/crossoverJie/Java-Interview)