如何让工作台窗口在基于Eclipse的项目中打开模态对话框？

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.swt.widgets.Shell;

public class ModalDialogExample {

    public static void main(String[] args) {
        Shell shell = new Shell();
        MessageDialog dialog = new MessageDialog(shell, "Modal Dialog", null, "This is a modal dialog.", MessageDialog.INFORMATION, new String[] { "OK", "Cancel" }, 0);
        dialog.open();
    }
}