如何在Java Swing for Hangman游戏中获取从监听器更新的文本字段？

I am trying to write a code from Hangman program. I am not sure if this idea is correct. I was thinking of having dashes (_ _ _ _ _) in textfield which must dynamically change when user presses buttons. for example, if the user presses button "A" in the below code, the the dashes should change to ( A _ _ _ _ ). That is the user has guessed the letter A correct. I am trying to write a code from Hangman progra