I feel that it will be a great job. An easy way out would be to simply put the JButtons under the numbers.
If you still feel like creating irregular clicks, I suggest creating Polygon instances (java.awt) for each country. They are created using arrays of points x and y, which define the angles. Conveniently enough, there is a Polygon.contains (x, y) method that lets you know if (x, y) is in your polygon. If you use a large JPanel that covers the entire map and gets the mouse location relative to the JPanel, you can notify each country about whether the mouse is inside it.
source share