Coding

#TeacherCode
private void setupListenersForValidation() {
		this.idTextField.textProperty().addListener((observable, oldValue, newValue) -> {
				if (newValue != null) {
					if (!newValue.matches("\\d{0,3}|(\\d{3}(-\\d{0,2}|-\\d{2}-\\d{0,4}))")) {
						CourseGuiCodeBehind.this.idTextField.setText(oldValue);
						CourseGuiCodeBehind.this.idErrorLabel.setVisible(true);
					} else {
						CourseGuiCodeBehind.this.idErrorLabel.setVisible(false);
					}
				}
		});
#MyCode

private void setupListenersForValidation() {
		this.phoneNumberTextField.textProperty().addListener((observable, oldValue, newValue) -> {
				if (newValue != null) {
					if (!newValue.matches("^\\(\\d{3}\\)\\d{3}-\\d{4}")) {
						ContactGuiCodeBehind.this.phoneNumberTextField.setText(oldValue);
						ContactGuiCodeBehind.this.idErrorLabel.setVisible(true);
					} else {
						ContactGuiCodeBehind.this.phoneNumberTextField.setText(newValue);
						ContactGuiCodeBehind.this.idErrorLabel.setVisible(false);
					}
				}
		});
	}