chars.add(randomAlpha());
    }
    for (int i = 0; i < nonAlpha; i++) {
      chars.add(randomNonAlpha());
    }
    Collections.shuffle(chars, random);
    char[] array = Chars.toArray(chars);
    this.testString = new String(array);
  }

  private char randomAlpha() {
    return ALPHA.charAt(random.nextInt(ALPHA.length()));
  }

  private char randomNonAlpha() {

      chars.add(randomAlpha());
    }
    for (int i = 0; i < nonAlpha; i++) {
      chars.add(randomNonAlpha());
    }
    Collections.shuffle(chars, random);
    char[] array = Chars.toArray(chars);
    this.testString = new String(array);
  }

  private char randomAlpha() {
    return ALPHA.charAt(random.nextInt(ALPHA.length()));
  }

  private char randomNonAlpha() {

        }
      }
    }
    if (ipString.charAt(0) == IPV6_DELIMITER && ipString.charAt(1) != IPV6_DELIMITER) {
      return null; // ^: requires ^::
    }
    if (ipString.charAt(ipString.length() - 1) == IPV6_DELIMITER
        && ipString.charAt(ipString.length() - 2) != IPV6_DELIMITER) {
      return null; // :$ requires ::$
    }

        chunk |= alphabet.decode(chars.charAt(i++)) << 12;
        target[bytesWritten++] = (byte) (chunk >>> 16);
        if (i < chars.length()) {
          chunk |= alphabet.decode(chars.charAt(i++)) << 6;
          target[bytesWritten++] = (byte) ((chunk >>> 8) & 0xFF);
          if (i < chars.length()) {
            chunk |= alphabet.decode(chars.charAt(i++));
            target[bytesWritten++] = (byte) (chunk & 0xFF);

                    boolean active = true;
                    if (!selector.isEmpty()) {
                        if (selector.charAt(0) == '-' || selector.charAt(0) == '!') {
                            active = false;
                            selector = selector.substring(1);
                        } else if (token.charAt(0) == '+') {
                            selector = selector.substring(1);
                        }

   *
   * @return the replacement characters, or {@code null} if no escaping was required
   */
  @Override
  protected final char @Nullable [] escape(int cp) {
    if (cp < replacementsLength) {
      char[] chars = replacements[cp];
      if (chars != null) {
        return chars;
      }
    }
    if (cp >= safeMin && cp <= safeMax) {
      return null;
    }
    return escapeUnsafe(cp);
  }

    for (int i = 0; i < len; i++) {
      buffer.putChar(input.charAt(i));
    }
    return hashBytes(buffer.array());
  }

  @Override
  public HashCode hashString(CharSequence input, Charset charset) {
    return hashBytes(input.toString().getBytes(charset));
  }

  @Override
  public abstract HashCode hashBytes(byte[] input, int off, int len);

  @Override

  }

  /** Helper to manually escape a 7-bit ascii character */
  private String escapeAscii(char c) {
    Preconditions.checkArgument(c < 128);
    String hex = "0123456789ABCDEF";
    return "%" + hex.charAt((c >> 4) & 0xf) + hex.charAt(c & 0xf);
  }

    String testString = "abcdef";
    Reader reader = new StringReader(testString);

    assertEquals(testString.charAt(0), reader.read());
    CharStreams.skipFully(reader, 1);
    assertEquals(testString.charAt(2), reader.read());
    CharStreams.skipFully(reader, 2);
    assertEquals(testString.charAt(5), reader.read());

    assertEquals(-1, reader.read());
  }

  public void testAsWriter() {

    String testString = "abcdef";
    Reader reader = new StringReader(testString);

    assertEquals(testString.charAt(0), reader.read());
    CharStreams.skipFully(reader, 1);
    assertEquals(testString.charAt(2), reader.read());
    CharStreams.skipFully(reader, 2);
    assertEquals(testString.charAt(5), reader.read());

    assertEquals(-1, reader.read());
  }

  public void testAsWriter() {