TestBackground

package testbackground;

import java.awt.EventQueue;
import java.awt.FlowLayout;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;


public class TestBackground extends JFrame {

    public TestBackground() {
        setTitle("TestBackground");
        setSize(800, 600);
        setResizable(false);

        JLabel contentPane = new JLabel(new ImageIcon("background.jpg"));
        setContentPane( contentPane );


        JPanel panel = new JPanel();
        panel.add(new JButton("Prueba"));
        panel.setLayout(new FlowLayout(FlowLayout.LEFT, 0, 0));
        add(panel);
        setLayout(new FlowLayout());


        setLocationRelativeTo(null);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    }


    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                TestBackground app = new TestBackground();
                app.setVisible(true);
            }
        });
    }
}