code: private static void setDerivedFont(JTable t, float size)
      {
          t.setFont(t.getFont().deriveFont(size));
          t.getTableHeader().setFont(
              t.getTableHeader().getFont().deriveFont(size));
      }
docs: Set a derived font with the given size for the given
  table and its header
  
  @param t The table
  @param size The font size