import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Insets;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
public class BorderExample {
public static void main(String[] args) {
JPanel panel = new JPanel(new BorderLayout());
JPanel top = new JPanel();
top.setBackground(Color.gray);
top.setPreferredSize(new Dimension(250, 150));
panel.add(top);
panel.setBorder(new EmptyBorder(new Insets(10, 20, 30, 40)));
JFrame f = new JFrame();
f.add(panel);
f.pack();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
}