Java Swing Button Mouseover color change

import java.awt.Color;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JButton;
import javax.swing.JFrame;

public class Main {

    public static void main(String[] args) {
        JFrame jf = new JFrame();

        JButton justinBieber = new JButton("Botao doidao!");
        jf.getContentPane().add(justinBieber);
        justinBieber.setBackground(Color.RED);
        justinBieber.setOpaque(true);
        justinBieber.addMouseListener(
                new MouseAdapter() {
                    @Override
                    public void mouseEntered(MouseEvent e) {
                        super.mouseEntered(e);
                        JButton jb = (JButton) e.getSource();
                        jb.setBackground(Color.BLUE);
                    }
                    @Override
                    public void mouseExited(MouseEvent e) {
                        super.mouseExited(e);
                        // sua logica pra quando o mouse sair
                    }

                }
        );

        jf.setSize(400, 400);
        jf.setVisible(true);
    }
}