Enable a JButton when some component changed its border color

My goal is to enable a JButton only when some JTextFields and JComboBox change its border color from red to green.<br>
These components are included in three different JPanel.<br>
I try to create a function that reads all components in a JPanel but, when I'm going to compared the colors, the program returns me that I'm casting the variables in a bad way.<br>
Below there's my function.<br>
Can someone help me?

    public static boolean countBoards(JPanel panel){
        boolean red = false;
        
        for(Component control : panel.getComponents())
        {
            if(control instanceof JTextField)
            {
                JTextField ctrl = (JTextField) control; 
                Color lineColor = ((LineBorder)ctrl.getBorder()).getLineColor();
            
                if(lineColor.equals(Color.red))
                    red = true;                
            }  
            else if(control instanceof JComboBox)
            {
                JComboBox ctr = (JComboBox) control; 
                Color lineColor = ((LineBorder)ctr.getBorder()).getLineColor();
            
                if(lineColor.equals(Color.red))
                    red = true;               
            }
        }                 
        
        return red;
    }

When you change the border of a component, a property listener will be fired. You can register a property listener to the combobox/textfield and enable/disable the button according to the new border.

An example:

@Test
public void test() {
	JButton myButton = new JButton();
	JComboBox<String> combo = new JComboBox<>();
	combo.addPropertyChangeListener("border", e -> {
		if (e.getNewValue() != null && e.getNewValue() instanceof LineBorder) {
			LineBorder border = (LineBorder) e.getNewValue();
			myButton.setEnabled(border.getLineColor().equals(Color.green));
		}
	});
	assertTrue(myButton.isEnabled(), "Button should be initially enabled.");

	combo.setBorder(BorderFactory.createLineBorder(Color.red));
	assertFalse(myButton.isEnabled(), "Button should be disabled when red line border occurs.");

	combo.setBorder(BorderFactory.createLineBorder(Color.green));
	assertTrue(myButton.isEnabled(), "Button should be enabled when green line border occurs.");
}