JAVA Input hintergrund

import java.awt.Color;import java.awt.event.FocusEvent;import java.awt.event.FocusListener;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JTextField;public class c {	public c(){		JFrame frame = new JFrame();		frame.setBounds(0, 0, 800, 600);		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);		JPanel contentPane =new JPanel();		contentPane.setLayout(null);		frame.setContentPane(contentPane);		final JTextField tf = new JTextField();		FocusListener fl = new FocusListener(){			@Override			public void focusGained(FocusEvent arg0) {				tf.setBackground(Color.red);			}			@Override			public void focusLost(FocusEvent arg0) {				tf.setBackground(Color.blue);			}		};		tf.addFocusListener(fl);		tf.setBounds(10, 10, 100, 20);		contentPane.add(tf);		JButton button = new JButton("asd");		button.setBounds(59, 49, 324, 23);		contentPane.add(button);		frame.setVisible(true);	}	public static void main(String args[]){		new c();	}}

Klick mich: <input name="vorname" id="wasauchimmer" type="text">

var element = document.getElementById( 'wasauchimmer' );
element.onfocus = function(event) {
    element.style.backgroundColor='#00FF00';
};
element.onblur = function(event) {
    element.style.backgroundColor='#0000FF';
};

#deineID {
background-color: red;
}


#deineID:focus {
background-color: blue;
}