How do I add key listener event handler to JTextField?

In this small swing example we demonstrate how to use KeyAdapter class to handle keyboard event for the text field component to change the text-field’s text to uppercase.

  • MadProgrammer

    No offense, but this is a bad approach and could lead to mutation errors caused by the underlying Document been in a state of flux when the key event is triggered. It also does not take into account what will happen if the user pastes text into the field. A DocumentFilter would be a better and safer choice and is the reason it was implemented, just for this type of use case

    • Wayan Saryada

      Thank you for you correction, I will try to update the example then.