IntelliJ just inserts them automagically; no shortcut required. If the class name is ambiguous, it'll show me the list of possibilities to choose from. It reads my mind....
You also can enable this import as automatic operation. In the properties dialog of your Java projects, enable organize imports via Java Editor - Save Action. After saving your Java files, IDE will do organizing imports, formatting code and so on for you.
Alt + Shift + Arrow Keys: selects enclosing elements
Alt + Shift + F1: Focus on eclipse element to know plugin implementation details.
Alt + Shift + F2: Plugin implementation details.
F4 : Type Hierarchy
Ctrl + Shift + T : OpenType
Ctrl + Shift + H: Open Type in Hierarchy
Ctrl + Alt + H: Call Hierarchy
Ctrl + Shift + G: Reference in workspace
Ctrl + Alt + G: Quick Search for selected text
Ctrl + Shift + O: Organize imports
Ctrl + Shift + M: Add import for currently selected.
Ctrl + Shift + L: Shows you a List of your currently defined shortcut keys
Ctrl + Shift + U: Occurrence in current file
Ctrl + Shift + A: Open plug-in Artifact
Ctrl + Shift + {: Two side by side editors with current file
Ctrl + Shift + Space : Parameter Hints
Ctrl + Shift + Mouse hover : To view javadoc
Shift + Mouse hover : To view source code
Ctrl + Space : Content Assist
Ctrl + F3/O : Outline
Ctrl + T: Type Hierarchy
Ctrl + H : Open Search Dialog
Ctrl + 1 : Quick Fix
Ctrl+Shift+NUM_KEYPAD_DIVIDE : Collapse All code blocks
Ctrl+Shift+NUM_KEYPAD_MULTIPLY : To open all code blocks
Alt + left arrow : Open recently closed file
Ctrl+Shift+ any key :Direct actions (on text mostly)
Alt+Shift+ any key : Indirect actions
Ctrl It is originally used with other chars by shell for perform special function. (In Mac Command)
Alt It enables alternate uses for other keys.
The above shortcuts are default, if we want to change shortcuts we can do. In eclipse -> Windows -> preferences -> keys. Where we can find all shortcuts with full details: