Capitalize all letters in a Textfield in Java

Question

Is it to possible to capitalize the letters in a Textfield as they are being typed by the user in Java?

E.g. The user would type 'hello' and 'HELLO' would appear in the Textfield.

(Odd request and I don't like the idea either).

Answer 1

ModifyListener and getText().toUpperCase() are your friends.

Answer 2

Format JTextField's text to uppercase

Uses DocumentFilter

or

How to Use Formatted Text Fields

Uses MaskFormatter

Answer 3

This is probably an inefficient way to do it

but you could have a section in your KeyTyped event handler

if(event.getSource() == capitalTextArea) {
    String text = capitalTextArea.getText();
    if(Character.isLowerCase(text.charAt(text.length()-1))) {
        capitalTextArea.setText(text.toUpperCase());
    }
}

I might have syntatical mistakes, but that's the apporach i'd take