Java by API/javax.swing/OverlayLayout

new OverlayLayout(Container target)

 
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.LayoutManager;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.OverlayLayout;
public class Main {
  public static void main(String args[]) {
    JFrame frame = new JFrame("Overlay Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JPanel panel = new JPanel() {
      public boolean isOptimizedDrawingEnabled() {
        return false;
      }
    };
    LayoutManager overlay = new OverlayLayout(panel);
    panel.setLayout(overlay);
    JButton button = new JButton("Small");
    button.setMaximumSize(new Dimension(25, 25));
    button.setBackground(Color.white);
    panel.add(button);
    
    button = new JButton("Medium");
    button.setMaximumSize(new Dimension(50, 50));
    button.setBackground(Color.gray);
    panel.add(button);
    
    button = new JButton("Large");
    button.setMaximumSize(new Dimension(100, 100));
    button.setBackground(Color.black);
    panel.add(button);    
    frame.add(panel, BorderLayout.CENTER);
    frame.setSize(400, 300);
    frame.setVisible(true);
  }
}