Detect selected text (or similar) using java for click to dial application

I want to write a click to dial application that works on Windows / Mac / Linux. The user should be able to rapidly select a telephone number in some way then press keys / mouse in order to dial the number. The rest of the program is written in Java. I do not need assistance with the phone part, just the part where the user selects what number to dial. My idea is to somehow detect or copy into clipboard the currently selected text. I'm open to other solutions especially solutions that make selecting the number to call more efficient. I'm happy for the solution to involve com wrappers for Windows and whatever the equivalent is for Mac / Linux however I'll need assistance with the installation method to automatically set up whichever is needed.