package jdraganddropdemo;import java.awt.*;import java.awt.event.*;import javax.swing.*;public class MainFrame extends JFrame {  private JPanel contentPane;  private BorderLayout borderLayout1 = new BorderLayout();  //Construct the frame  public MainFrame() {    enableEvents(AWTEvent.WINDOW_EVENT_MASK);    try {      jbInit();    }    catch(Exception e) {      e.printStackTrace();    }  }  //Component initialization  private void jbInit() throws Exception  {    //setIconImage(Toolkit.getDefaultToolkit().createImage(MainFrame.class.getResource("[Your Icon]")));    contentPane = (JPanel) this.getContentPane();    contentPane.setLayout(borderLayout1);    this.setSize(new Dimension(403, 211));    this.setTitle("JDragAndDropDemo");  }  //Overridden so we can exit when window is closed  protected void processWindowEvent(WindowEvent e) {    super.processWindowEvent(e);    if (e.getID() == WindowEvent.WINDOW_CLOSING) {      System.exit(0);    }  }}