public int length() {
                    return name.length();
                }

                @Override
                public CharSequence subSequence(final int start, final int end) {
                    return name.subSequence(start, end);
                }

            };
        }

        /**
         * @return CharSequence
         */
        public static CharSequence aaa() {

      return 3;
    }

    @Override
    public char charAt(int index) {
      return "foo".charAt(index);
    }

    @Override
    public CharSequence subSequence(int start, int end) {
      return "foo".subSequence(start, end);
    }

    @Override
    public String toString() {
      throw new AssertionFailedError("shouldn't be invoked");
    }
  }

  // Don't do this.

    int p = 0;
    while (p < maxPrefixLength && a.charAt(p) == b.charAt(p)) {
      p++;
    }
    if (validSurrogatePairAt(a, p - 1) || validSurrogatePairAt(b, p - 1)) {
      p--;
    }
    return a.subSequence(0, p).toString();
  }

  /**
   * Returns the longest string {@code suffix} such that {@code a.toString().endsWith(suffix) &&

      TF_ASSIGN_OR_RETURN(
          int matches,
          fieldTagMatches(chunked_field.field_tag(), target_fields));
      if (matches == chunked_field.field_tag_size()) {
        // chunked_field_tags is an initial subsequence of target_fields, which
        // means the chunked_field is relevant and the necessary data should be
        // copied over.
        auto cf = std::make_unique<proto_splitter::ChunkedField>();

        Matcher matcher = WORD_SEPARATOR.matcher(string);
        int pos = 0;
        boolean first = true;
        while (matcher.find()) {
            String chunk = string.subSequence(pos, matcher.start()).toString();
            pos = matcher.end();
            if (chunk.isEmpty()) {
                continue;
            }
            if (lower && first) {

        Matcher matcher = WORD_SEPARATOR.matcher(string);
        int pos = 0;
        boolean first = true;
        while (matcher.find()) {
            String chunk = string.subSequence(pos, matcher.start()).toString();
            pos = matcher.end();
            if (chunk.isEmpty()) {
                continue;
            }
            if (lower && first) {

            int codePoint = Character.codePointAt(input, i);
            if (codePoint == c) {
              // fall back to JDK getBytes instead of trying to handle invalid surrogates ourselves
              putBytes(input.subSequence(i, utf16Length).toString().getBytes(charset));
              return this;
            }
            i++;
            update(4, codePointToFourUtf8Bytes(codePoint));
          }
        }
        return this;

            int codePoint = Character.codePointAt(input, i);
            if (codePoint == c) {
              // fall back to JDK getBytes instead of trying to handle invalid surrogates ourselves
              putBytes(input.subSequence(i, utf16Length).toString().getBytes(charset));
              return this;
            }
            i++;
            update(4, codePointToFourUtf8Bytes(codePoint));
          }
        }
        return this;

                public int length() {
                    return name.length();
                }

                @Override
                public CharSequence subSequence(final int start, final int end) {
                    return name.subSequence(start, end);
                }

            };
        }

        /**
         * @return CharSequence
         */

      char padChar = paddingChar.charValue();
      int l;
      for (l = chars.length() - 1; l >= 0; l--) {
        if (chars.charAt(l) != padChar) {
          break;
        }
      }
      return chars.subSequence(0, l + 1);
    }

    @Override
    public boolean canDecode(CharSequence chars) {
      checkNotNull(chars);
      chars = trimTrailingPadding(chars);