return internalFrameLayout.minimumLayoutSize(x);
Dimension min = null; LayoutManager layout = frame.getLayout(); if (frame == x && layout != null) min = layout.minimumLayoutSize(frame); else min = new Dimension(0, 0); return min;
  public Dimension getMinimumSize(JComponent x)  {    return internalFrameLayout.minimumLayoutSize(x);  }