private boolean checkChars(String text) {
			for (int i = 0; i < text.length(); i++) {
				char c = text.charAt(i);
				if (!checkChar(c)) {
					return false;
				}
			}
			return true;
		}
@see javax.swing.text.Document#insertString(int, java.lang.String, javax.swing.text.AttributeSet)
Ghidra/Framework/Docking/src/main/java/docking/widgets/textfield/HexOrDecimalInput.java