static JFrame showCenterFrame(S title, int w, int h) {
  ret showCenterFrame(title, w, h, null);
}

static JFrame showCenterFrame(S title, int w, int h, Component content) {
  JFrame frame = makeFrame(title, content);
  frame.setSize(w, h);
  ret centerFrame(frame);
}

static JFrame showCenterFrame(S title, Component content) {
  ret centerFrame(makeFrame(title, content));
}