public JValidTextField(Color validColor, Color errorColor) {
        this.addKeyListener(new KeyAdapter() {
            @Override
            public void keyReleased(KeyEvent e) {
                JValidTextField vTxtField = (JValidTextField) e.getSource();
                vTxtField.check();
            }
        });
        this.errorColor = errorColor;
        this.validColor = validColor;
    }