public String getKeyName(int key){
        return keys.getKeyName(key);
    }
Initializes the InputManager.

<p>This should only be called internally in {@link Application}.

@param mouse (not null, alias created)
@param keys (not null, alias created)
@param joystick (may be null, alias created)
@param touch (may be null, alias created)
@throws IllegalArgumentException If either mouseInput or keyInput are null.
jme3-core/src/main/java/com/jme3/input/InputManager.java