Instead of using a JFormattedTextField, you may write a custom JTextField with a document that allows only integers. I like formatted fields only for more complex masks...
Take a look.
import javax.swing.JTextField;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.PlainDocument;
/**
* A JTextField that accepts only integers.
*
* @author David Buzatto
*/
public class IntegerField extends JTextField {
public IntegerField() {
super();
}
public IntegerField( int cols ) {
super( cols );
}
@Override
protected Document createDefaultModel() {
return new UpperCaseDocument();
}
static class UpperCaseDocument extends PlainDocument {
@Override
public void insertString( int offs, String str, AttributeSet a )
throws BadLocationException {
if ( str == null ) {
return;
}
char[] chars = str.toCharArray();
boolean ok = true;
for ( int i = 0; i < chars.length; i++ ) {
try {
Integer.parseInt( String.valueOf( chars[i] ) );
} catch ( NumberFormatException exc ) {
ok = false;
break;
}
}
if ( ok )
super.insertString( offs, new String( chars ), a );
}
}
}
If you are using NetBeans to build your GUI, you just need to put regular JTextFields in your GUI and in the creation code, you will specify the constructor of IntegerField.
