等待定时器/过程完成后再继续

I have a function that flashes the border of a JButton which gets called multiple times in a row. I want the processes to continue only after the entirety of the function completes. Right now, the flashing starts for one button, then it will start for another before the flashing stopped for the first button. The function looks like the following which is in a class that extends JButton:I have a function that flashes the border of a