import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main extends JFrame {
public Main() {
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.NORTH;
gbc.weighty = 0.0;
JPanel one = new JPanel();
one.setPreferredSize(new Dimension(200, 200));
one.setBorder(BorderFactory.createLineBorder(Color.BLACK));
JPanel two = new JPanel();
two.setPreferredSize(new Dimension(200, 200));
two.setBorder(BorderFactory.createLineBorder(Color.BLACK));
this.add(one, gbc);
gbc.gridy = 1;
gbc.weighty = 0.0;
gbc.fill = GridBagConstraints.VERTICAL;
this.add(two, gbc);
this.pack();
this.setVisible(true);
}
public static void main(String[] args) {
new Main();
}
}