Eclipse has lots and lots of hotkeys, but for daily work you need only a small subset. This are the hotkeys I consider to be the most important time savers:
Moving around
    - Ctrl+J — Incremental Search  
 
    - Ctrl+Shift+T — Search a type, with search on typing. You can use only the upcase letters (e.g. type “MIL” to find MouseInputListener)  
 
    - Ctrl+F6 — Switch between last used files  
 
    - F3 — Open declaration
 
    - F4-- 查看类体系
 
    - Ctrl+Alt+H — Open Call Hierarchy 
 
Editing
    - Ctrl+1 — Quick Fix: press while cursor is positioned at member variable, parameter, selection, warnings, errors, …  
 
    - Ctrl+Space — Context Assist: press after a ., or to use macros (for, while, sysout, …). Press in class-scope to automatically create method declarations.  
 
    - Ctrl+Shift+O — Organize Imports  
 
    - Ctrl+Shift+F — Reformat source  
 
    - Alt+Shift+T — Show Refactor Quick Menu 
 
In case these hotkeys are not enough or you have forgotten which hotkey does what, you can always press Ctrl+Shift+L to get a nice list of all the hotkeys.