import java.awt.Insets;

import javax.swing.JFrame;

public class NewFrame {

    public static void main(String[] args) {

        JFrame frame = new JFrame();

        frame.setSize(500, 500);

        frame.setVisible(true);

        Insets insets = frame.getInsets();

        System.out.println(insets.top);

        System.out.println(insets.bottom);

        System.out.println(insets.left);

        System.out.println(insets.right);

    }

}

 import java.awt.Insets;

 import javax.swing.JFrame;

 public class NewFrame extends JFrame {

     public void launchFrame() {

         this.setSize(500, 500);

         this.setLocation(300, 300);

         this.setVisible(true);

     }

     public static void main(String[] args) {

         NewFrame nf = new NewFrame();

         nf.launchFrame();

         Insets insets = nf.getInsets();

         System.out.println(insets.top);

         System.out.println(insets.bottom);

         System.out.println(insets.left);

         System.out.println(insets.right);

     }

 }