Time limit to re-select a data

Hello everyone I am developing a desktop project in netbeans , but I want to add a restriction when selecting a data, that is: I have a frame where I show the employee data and also a botón that opens another frame where you can see the employees that I have in phpmyadmin , select them and send the data to my first frame , which I want to add, is that when selecting an employee, it can not be selected again after a certain time, for example half an hour or 15 minutes. I have been looking for videos and web pages to solve my doubt and I have not found anything, I would like to know how I can do it. Thank you. -------------------------------IMAGES------------------ ----------------

2. By clicking on the search button the frame appears to select the employee and send it to the first frame (this is where I want to put the time restriction)

3. The employee that was selected in the previous frame is displayed.