public APCircleWindow() {
    super("AP Circles");
    setDefaultCloseOperation(EXIT_ON_CLOSE);

    String startDirectoryName = System.getProperty("user.dir");
    startDirectory = new File(startDirectoryName);
    // this for convenience, as the program normally starts in graph/display
    //		startDirectory = startDirectory.getParentFile();

    gw = this;

    generalXML = new GeneralXML(graph);

    gp = new APCirclePanel(this);
    getContentPane().add(gp);

    graph = gp.getGraph();

    initView();
    initExperiment();
    initUtility();
    initLayout();
    initMenu();

    setSize(width, height);

    Dimension frameDim = Toolkit.getDefaultToolkit().getScreenSize();
    int posX = (frameDim.width - getSize().width) / 2;
    int posY = (frameDim.height - getSize().height) / 2;
    setLocation(posX, posY);

    setVisible(true);

    gp.requestFocus();
  }
 protected void fileExit() {
   System.exit(0);
 }