An object that encapsulate the interaction that a figure plays in
an interactive application. Typically, all objects of a certain
type (nodes in a graph viewer, for example) all have the same
interactor given to them, so that they behave the same. Each
interactor is thus attached to one or more figures in a canvas.
When a mouse event occurs on the figure canvas, the event dispatch
code in the figure canvas searches for the top-most figure
underneath the mouse, and then searches up the tree of figures
looking for an interactor that can handle that event.
Test is the interactor is prepared to accept this event. If
so, the event is passed to the interactor for handling. This
method is called only for the mouse-pressed and mouse-entered
events. If that event is accepted, other events of the same
series (dragged and released, or moved and exited,
respectively) are passed to the interactor without calling
this method to check. The mouse-entered event is called only
if isMotionEnabled() returns true.