static JFrame showFrame() {
  ret makeFrame();
}

static JFrame showFrame(O content) {
  ret makeFrame(content);
}

static JFrame showFrame(S title) {
  ret makeFrame(title);
}

static JFrame showFrame(String title, O content) {
  ret makeFrame(title, content);
}

static JFrame showFrame(final JFrame f) {
  if (f != null) swing {
    if (frameTooSmall(f)) frameStandardSize(f);
    if (!f.isVisible()) f.setVisible(true); // XXX
    if (f.getState() == Frame.ICONIFIED) f.setState(Frame.NORMAL);
  }
  ret f;
}

// make or update frame
static JFrame showFrame(String title, O content, JFrame frame) {
  if (frame == null)
    ret showFrame(title, content);
  else {
    frame.setTitle(title);
    setFrameContents(frame, content);
    ret frame;
  }
}

Began life as a copy of #1000921