查看帮助：Help | Tip of the Day
快速打开类：Ctrl+N (Navigate | Class)
快速补全： Ctrl+空格
查看方法在哪里使用：Alt+F7 (Edit | Find | Find Usages )
查看类的文档： Ctrl+Q (View | Quick Documentation)
查看变量的生命的位置： Ctrl+B (Navigate | Declaration) || ctrl+click
大纲视图：Ctrl+F12 (Navigate | File Structure)
类的重命名：Shift+F6 (Refactor | Rename)
重写方法： Ctrl+O (Code | Override Methods).
实现方法： Ctrl+I (Code | Implement methods).
查找最适合的参数：输入部分后 press Ctrl+Shift+空格
自动补全tab的坑：
When using Code Completion, you can accept the currently highlighted selection in the popup list with Tab key.
Unlike accepting with the Enter key, the selected name will overwrite the rest of the name to the right of the caret. This can be especially useful for replacing one method or variable name with another.
快速关闭tabs页：
Did you know that you can close tabs in the editor and the tool windows of IntelliJ IDEA without actually using the context menu commands? It is enough to point with your mouse cursor to a tab to be closed, and click the middle mouse button, or just use the Shift+click combination.
快速生成set get 方法:Alt+Insert (Code | Generate)
快速选中： Alt+F1
快速返回编辑框：The Esc key in any tool window moves the focus to the editor.
Shift+Esc moves the focus to the editor and also hides the current (or last active) tool window.
快速返回工具框：
The F12 key moves the focus from the editor to the last focused tool window.
快速try catch:Ctrl+Alt+T
快速添加new 的类名 ： Ctrl+Shift+空格
接口的实现方法快速查找： Ctrl+Alt+B
单行注释与多行注释： Ctrl+斜杠 and Ctrl+Shift+斜杠.
类型转换时： Ctrl+Shift+空格
只能变量名：Ctrl+空格.
快速生成参数：Ctrl+P（光标在括号内）
上次编辑的位置：Ctrl+Shift+Backspace (Navigate | Last Edit Location)
变量高亮显示： Ctrl+Shift+F
定位高亮： F3
取消高亮：escape
快速查看方法生命： Alt+Q (View | Context Info)
快速查看最近编辑的文档：Ctrl+E (View | Recent Files)
错误定位切换：F2/Shift+F2
快速查看不清楚的变量： Ctrl+J
快速切换方法：Alt+向上箭头 and Alt+向下箭头
黏贴： Ctrl+Shift+V
寻找父类： Ctrl+H (Navigate | Type Hierarchy).
尝试运行一段代码：hold Alt and click this expression to see its value and calculate it, call a method, etc.
最近变动文档： Alt+Shift+C
快速补全代码： Ctrl+Shift+Enter
快速查看定义：Ctrl+Shift+I (View | Quick Definition)
查看jdk类： Ctrl+Alt+Shift+C:
返回源代码编辑： Ctrl+V
运行或者调试： Alt+Shift+F10
查找：Ctrl+F
比较： Ctrl+D.
提交历史：Ctrl+K