求教啊着是为什么啊解决方法

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseAdapter;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.MessageBox;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

public class World {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        final Display display = Display.getDefault();
        final Shell shell = new Shell();
        shell.setSize(327, 253);
        shell.setText("linux");
        Text text = new Text(shell, SWT.BORDER);
        Button button = new Button(shell, SWT.BUTTON1);
        button.setBounds(100, 100, 70, 70);
        text.addMouseListener(new MouseAdapter(){
                public void mouseDoubleClick(MouseEvent E){
                    MessageBox mbox = new MessageBox(shell);
                    mbox.setMessage("window");
                    mbox.open();
                }
            });
        text.setText("helloworld");
        text.setBackground(null);
        text.setBounds(200, 166, 100, 100);
        shell.layout();
        shell.open();
        while(!shell.isDisposed()){
            if(!display.readAndDispatch())
                display.sleep();
        }

    }
}