Formatted text field is a feature in Java programming that lets you control the input in your JTextFields.
In Netbeans IDE, you cannot just edit the codes anywhere you like it if the GUI is generated by the IDE. This may mean that putting your formatting code would take you some time by overriding the class, function, etc (That's how you usually customize Netbeans - generated codes). However, there's a shorter way to do that, follow these steps:
1. Right click on the JFormattedTextField and select Customize Code
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