Keymap：Mac OS X
idea快速清除无用的引用
Ctrl+Alt+O
跳转：
Next project window : alt + command + ]
Previous project window : alt + command + [
Recent file: Command + E
recent changes : alt + shift + c
recently changed files : shift + command + E
Last edit loaction : shift + command + del
Next edit loaction :
Back : alt + command + left
forward : alt + command + right
查找：
Class : command + n
File : shift + command + n
## 查找方法、属性
Symbol : shift + alt + command + n
## 查找字符串
Find in path : ctrl + shift + f
