*/
  public static char toLowerCase(char c) {
    return isUpperCase(c) ? (char) (c ^ CASE_MASK) : c;
  }

  /**
   * Returns a copy of the input string in which all {@linkplain #isLowerCase(char) lowercase ASCII
   * characters} have been converted to uppercase. All other characters are copied without
   * modification.
   */
  public static String toUpperCase(String string) {
    int length = string.length();

    // than wrapping cbuf in a light-weight CharSequence.
    target.append(new String(cbuf, off, len));
  }

  /*
   * Override a few functions for performance reasons to avoid creating unnecessary strings.
   */

  @Override
  public void write(int c) throws IOException {
    checkNotClosed();
    target.append((char) c);
  }

  @Override

      }
    },
    // It really seems like this should be faster than TO_BYTE_ARRAY_NEW_STRING.  But it just isn't
    // my best guess is that the jdk authors have spent more time optimizing that callpath than this
    // one. (StringCoding$StringDecoder vs. StreamDecoder).  StringCoding has a ton of special cases
    // theoretically we could duplicate all that logic here to try to beat 'new String' or at least
    // come close.

  static char randomLowSurrogate(Random random) {
    return (char)
        (Character.MIN_LOW_SURROGATE
            + random.nextInt(Character.MAX_LOW_SURROGATE - Character.MIN_LOW_SURROGATE + 1));
  }

  static char randomHighSurrogate(Random random) {
    return (char)
        (Character.MIN_HIGH_SURROGATE
            + random.nextInt(Character.MAX_HIGH_SURROGATE - Character.MIN_HIGH_SURROGATE + 1));
  }

//
// Use in tests to allow XLA to fallback to TF classic. This has global effect.
TF_CAPI_EXPORT unsigned char TF_SetXlaEnableLazyCompilation(
    unsigned char enable);
TF_CAPI_EXPORT unsigned char TF_SetTfXlaCpuGlobalJit(unsigned char enable);

// Sets XLA's auto jit mode according to the specified string, which is parsed
// as if passed in XLA_FLAGS. This has global effect.

    }
    return builder.toString();
  }

  /**
   * Returns a comparator that compares two arrays of unsigned {@code long} values <a
   * href="http://en.wikipedia.org/wiki/Lexicographical_order">lexicographically</a>. That is, it
   * compares, using {@link #compare(long, long)}), the first pair of values that follow any common
   * prefix, or when one array is a prefix of the other, treats the shorter array as the lesser. For

  // original character value.
  @VisibleForTesting
  static char[][] createReplacementArray(Map<Character, String> map) {
    checkNotNull(map); // GWT specific check (do not optimize)
    if (map.isEmpty()) {
      return EMPTY_REPLACEMENT_ARRAY;
    }
    char max = max(map.keySet());
    char[][] replacements = new char[max + 1][];
    for (Character c : map.keySet()) {

    }

    /**
     * Validates that a given file is safe and does not attempt path traversal attacks.
     * <p>
     * This is a convenience method that converts File objects to Path and calls
     * {@link #isPathSafe(Path, Path)}.
     * </p>
     *
     * @param fileToCheck the file to validate (must not be {@literal null})
     * @param baseDirectory the base directory that the file must be within (must not be {@literal null})

 * that you implement a {@link Funnel}{@code <T>} to specify how to "feed" data from that object
 * into the function. (See {@linkplain Hasher#putObject an example} of this.)
 *
 * <p><b>Compatibility note:</b> Throughout this API, multibyte values are always interpreted in
 * <i>little-endian</i> order. That is, hashing the byte array {@code {0x01, 0x02, 0x03, 0x04}} is

 * that you implement a {@link Funnel}{@code <T>} to specify how to "feed" data from that object
 * into the function. (See {@linkplain Hasher#putObject an example} of this.)
 *
 * <p><b>Compatibility note:</b> Throughout this API, multibyte values are always interpreted in
 * <i>little-endian</i> order. That is, hashing the byte array {@code {0x01, 0x02, 0x03, 0x04}} is