Tooltip for a rectangleFigure

hello this is my problem:
i have built a graphic (with pPlot that extends Jpanel) for insert my
RectangleFigure.
RectangleFigure is an object with some properties(private String
description,private int duration etc...). Now when the mouse is over a
rectangle i would like to see a toolTip with its description. Can you
help me?
thanks

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