eclipse中的Ctrl Alt H和f4有什么区别

Question

I'm not able to understand the difference between Ctrl+Alt+H and F4 in eclipse.

I see both of them providing the same results. The only two differences is see is :

1)While Ctrl+Alt+H loads on the Direct Callers and loads indirect callers only if we navigate through them , F4 loads them all in one go.

2)Ctrl+Alt+H is not available on an interface while F4 is.

Is there any other significant difference between the two and is my understanding correct with reference to the two points mentioned?

Answer 1

CTRL+ALT+H opens the Call Hierarchy F4 opens the Type Hierarchy

The Call Hierarchy is available for any member of a class, if you select a method name and press CTRL+ALT+H you will see all members in your workspace that call this method (very useful to see what is depending on a method/constructor/field). Try to press CTRL+ALT+H when your cursor is not on a member name or body (ie between method declarations), you will see an error "Operation unavailable on the current selection. Select one or more methods, classes, fields, or initializers". The call hierarchy is where we see both direct and indirect callers.

The Type Hierarchy is only available for types, clicking on a type name in your code and pressing F4 will display that type's superclasses all they way up to Object. If your cursor is not focused on a type name then pressing F4 will open the type hierarchy for the class in the currently displayed file. The type hierarchy shows neither direct nor indirect callers.

Answer 2

F4 opens the Type Hierarchy view and Ctrl + Alt + H opens the Call Hierarchy view.

The Type Hierarchy does not show the Direct Callers rather than the Classes it extends and extending it. Thats also the reason why its available on an Interface while the Call hierarchy is not (The Call Hierarchy of a class shows all callers of its constructor, and an interface has no constructor)