* the {@code charSequence} is mutated while it is being read, so don't do that.
   *
   * @since 15.0 (since 14.0 as {@code CharStreams.asCharSource(String)})
   */
  public static CharSource wrap(CharSequence charSequence) {
    return charSequence instanceof String
        ? new StringCharSource((String) charSequence)
        : new CharSequenceCharSource(charSequence);
  }

  /**

   * the {@code charSequence} is mutated while it is being read, so don't do that.
   *
   * @since 15.0 (since 14.0 as {@code CharStreams.asCharSource(String)})
   */
  public static CharSource wrap(CharSequence charSequence) {
    return charSequence instanceof String
        ? new StringCharSource((String) charSequence)
        : new CharSequenceCharSource(charSequence);
  }

  /**

    checkNotClosed();
    target.append(c);
    return this;
  }

  @Override
  public Writer append(@Nullable CharSequence charSeq) throws IOException {
    checkNotClosed();
    target.append(charSeq);
    return this;
  }

  @Override
  public Writer append(@Nullable CharSequence charSeq, int start, int end) throws IOException {
    checkNotClosed();
    target.append(charSeq, start, end);
    return this;

    public <T> Iterable<? super String> wildcardsMatchByLowerBound(
        List<? super CharSequence> list) {
      return isSubtype(list);
    }

    @TestSubtype(suppressGetSupertype = true, suppressGetSubtype = true)
    public <T> Iterable<? super CharSequence> wildCardsDoNotMatchByLowerBound(
        List<? super String> list) {
      return notSubtype(list);
    }

     * @param elements the elements to join
     * @return elements separated by delimiter
     */
    public static String join(final CharSequence delimiter, final CharSequence... elements) {
        final StringBuilder sb = new StringBuilder();
        for (final CharSequence element : elements) {
            if (sb.length() > 0) {
                if (delimiter != null) {
                    sb.append(delimiter);

        return str == null ? defaultStr : str;
    }

    /**
     * <p>Checks if the CharSequence contains only ASCII printable characters.</p>
     *
     * <p>{@code null} will return {@code false}.
     * An empty CharSequence (length()=0) will return {@code true}.</p>
     *
     * <pre>
     * StringUtils.isAsciiPrintable(null)     = false

    k1 = mixK1(high);
    h1 = mixH1(h1, k1);

    return fmix(h1, Longs.BYTES);
  }

  @Override
  public HashCode hashUnencodedChars(CharSequence input) {
    int h1 = seed;

    // step through the CharSequence 2 chars at a time
    for (int i = 1; i < input.length(); i += 2) {
      int k1 = input.charAt(i - 1) | (input.charAt(i) << 16);
      k1 = mixK1(k1);
      h1 = mixH1(h1, k1);

    return this;
  }

  /*
   * Note: hashString(CharSequence, Charset) is intentionally not overridden.
   *
   * While intuitively, using CharsetEncoder to encode the CharSequence directly to the buffer (or
   * even to an intermediate buffer) should be considerably more efficient than potentially
   * copying the CharSequence to a String and then calling getBytes(Charset) on that String, in

     * @return A {@link CopyOptions} with the specified property names to include in the operation.
     * @see CopyOptions#include(CharSequence...)
     */
    public static CopyOptions include(final CharSequence... propertyNames) {
        return new CopyOptions().include(propertyNames);
    }

    /**

   * putUnencodedChars}.
   *
   * @since 15.0 (since 11.0 as putString(CharSequence)).
   */
  @CanIgnoreReturnValue
  @Override
  Hasher putUnencodedChars(CharSequence charSequence);

  /**
   * Equivalent to {@code putBytes(charSequence.toString().getBytes(charset))}.
   *
   * <p><b>Warning:</b> This method, which reencodes the input before hashing it, is useful only for