// Valid radix values are Character.MIN_RADIX to Character.MAX_RADIX, inclusive.
    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MIN_RADIX - 1));

    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MAX_RADIX + 1));

          // Mostly 3-byte UTF-8 sequences - "Asian" text
          return Character.MIN_SUPPLEMENTARY_CODE_POINT;
        } else if (userFriendly.matches("(?i)(?:Cuneiform|rare|exotic|supplementary.*)")) {
          // Mostly 4-byte UTF-8 sequences - "rare exotic" text
          return Character.MAX_CODE_POINT;
        } else {
          throw new IllegalArgumentException("Can't decode codepoint " + userFriendly);

 *
 * <p><b>Warning:</b> Using a specific character encoding when hashing a {@link CharSequence} with
 * {@link #putString(CharSequence, Charset)} is generally only useful for cross-language
 * compatibility (otherwise prefer {@link #putUnencodedChars}). However, the character encodings
 * must be identical across languages. Also beware that {@link Charset} definitions may occasionally

   *                  str -> str.substring(1).chars().mapToObj(c -> (char) c));
   *
   * // is equivalent to
   *
   * static final ImmutableListMultimap<Character, Character> FIRST_LETTER_MULTIMAP =
   *     ImmutableListMultimap.<Character, Character>builder()
   *         .putAll('b', Arrays.asList('a', 'n', 'a', 'n', 'a'))
   *         .putAll('a', Arrays.asList('p', 'p', 'l', 'e'))
   *         .putAll('c', Arrays.asList('a', 'r', 'r', 'o', 't'))

   */
  @VisibleForTesting
  static boolean validSurrogatePairAt(CharSequence string, int index) {
    return index >= 0
        && index <= (string.length() - 2)
        && Character.isHighSurrogate(string.charAt(index))
        && Character.isLowSurrogate(string.charAt(index + 1));
  }

  /**
   * Returns the given {@code template} string with each occurrence of {@code "%s"} replaced with

        BytesRef matchOutput = null;

        int index = 0;
        while (start + index < src.length) {
            final int codePoint = Character.codePointAt(src, start + index, src.length);
            if (fst.findTargetArc(ignoreCase ? Character.toLowerCase(codePoint) : codePoint, scratchArc, scratchArc, fstReader) == null) {
                return matchOutput;
            }

    super(false, true, true, true);
  }

  @Override
  Table<String, Integer, Character> makeTable() {
    Table<String, Integer, String> original = HashBasedTable.create();
    return transformValues(original, TableCollectionTest.FIRST_CHARACTER);
  }

  @Override
  protected Map<String, Map<Integer, Character>> makePopulatedMap() {
    Table<String, Integer, String> table = HashBasedTable.create();

   * @throws IllegalArgumentException if {@code radix} is not between {@link Character#MIN_RADIX}
   *     and {@link Character#MAX_RADIX}.
   * @since 13.0
   */
  public static String toString(byte x, int radix) {
    checkArgument(
        radix >= Character.MIN_RADIX && radix <= Character.MAX_RADIX,
        "radix (%s) must be between Character.MIN_RADIX and Character.MAX_RADIX",
        radix);

     * @return Separator for grouping
     */
    public static String findGroupingSeparator(final Locale locale) {
        final DecimalFormatSymbols symbol = getDecimalFormatSymbols(locale);
        return Character.toString(symbol.getGroupingSeparator());
    }

    /**
     * Returns the separator for decimal numbers.
     *
     * @param locale
     *            Locale
     * @return Separator for decimal numbers

        final String delim = NumberConversionUtil.findDecimalSeparator(null);
        final char c = new DecimalFormatSymbols(LocaleUtil.getDefault()).getDecimalSeparator();
        assertEquals(Character.toString(c), delim);
    }

    /**
     * @throws Exception
     */
    public void testFindIntegerDelimeter() throws Exception {