private FsPermission() {}
@Test
  public void testFsPermission() {
    String symbolic = "-rwxrwxrwx";

    for(int i = 0; i < (1 << 10); i++) {
      StringBuilder b = new StringBuilder("----------");
      String binary = String.format("%11s", Integer.toBinaryString(i));
      String permBinary = binary.substring(2, binary.length());

      int len = permBinary.length();
      for(int j = 0; j < len; j++) {
        if (permBinary.charAt(j) == '1') {
          int k = 9 - (len - 1 - j);
          b.setCharAt(k, symbolic.charAt(k));
        }
      }

      // Check for sticky bit.
      if (binary.charAt(1) == '1') {
        char replacement = b.charAt(9) == 'x' ? 't' : 'T';
        b.setCharAt(9, replacement);
      }

      assertEquals(i, FsPermission.valueOf(b.toString()).toShort());
    }
  }