import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
public class RelativeY {
public static void main(String[] args) {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container pane = f.getContentPane();
pane.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
pane.add(new JButton("First column"), gbc);
gbc.gridx = 1;
gbc.gridy = GridBagConstraints.RELATIVE;
pane.add(new JButton("Second column, first row"), gbc);
pane.add(new JButton("Second column, second row"), gbc);
pane.add(new JButton("Second column, third row"), gbc);
gbc.gridx = 2;
pane.add(new JButton("Third column"), gbc);
f.setSize(500, 300);
f.setVisible(true);
}
}