import java.awt.BorderLayout;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ScrollPaneConstants;
public class MainClass extends JPanel {
public MainClass() {
setLayout(new BorderLayout());
JPanel jp = new JPanel();
jp.setLayout(new GridLayout(20, 20));
int b = 0;
for (int i = 0; i < 20; i++) {
for (int j = 0; j < 20; j++) {
jp.add(new JButton("Button " + b));
++b;
}
}
// Add panel to a scroll pane.
int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED;
int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED;
JScrollPane jsp = new JScrollPane(jp, v, h);
// Add scroll pane to the content pane.
add(jsp, BorderLayout.CENTER);
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.getContentPane().add(new MainClass());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(200, 200);
frame.setVisible(true);
}
}