How to get cursor position relative to screen in JTextArea?

Question

Java

I downloaded the library for code completion for JTextArea, but the functionality did not meet the desired requirements, and I decided to write my own library, I ran into the fact that I could not get the cursor coordinates (textArea.getCaretPosition()) relative to the entire screen, to set the window position for selection auto-completion, but in that library they somehow did it. How can this be implemented?

Old Library: AutoComplete by Fifesoft