while (remaining > 0) {
      final char c = (char) random.nextInt();
      if (bitSet.get(c)) {
        final int pos = random.nextInt(result.length);
        if (bitSet.get(result[pos])) {
          result[pos] = c;
          remaining--;
        }
      }
    }
    return new String(result);
  }

       * roundArbitrarilyAsLong is Long.MAX_VALUE. (This is the only way this condition can occur as
       * otherwise the conversion back to long pads with zero bits.) In this case we know that
       * roundArbitrarily > x. (This is important when x == Long.MAX_VALUE ==
       * roundArbitrarilyAsLong.)
       */
      cmpXToRoundArbitrarily = -1;
    } else {

  /**
   * This is invoked for the last bytes of the input, which are not enough to fill a whole chunk.
   * The passed {@code ByteBuffer} is guaranteed to be non-empty.
   *
   * <p>This implementation simply pads with zeros and delegates to {@link #process(ByteBuffer)}.
   */
  protected void processRemaining(ByteBuffer bb) {
    Java8Compatibility.position(bb, bb.limit()); // move at the end

      assertTrue(bb.remaining() < bufferSize);
      int before = processCalled;
      super.processRemaining(bb);
      int after = processCalled;
      assertEquals(before + 1, after); // default implementation pads and calls process()
      processCalled--; // don't count the tail invocation (makes tests a bit more understandable)
    }

    // ensures that the number of invocations looks sane

   * needed again; and for short-lived ones, it does not matter.
   */

  /**
   * Padded variant of AtomicLong supporting only raw accesses plus CAS. The value field is placed
   * between pads, hoping that the JVM doesn't reorder them.
   *
   * <p>JVM intrinsics note: It would be possible to use a release-only form of CAS here, if it were
   * provided.
   */
  static final class Cell {

   * needed again; and for short-lived ones, it does not matter.
   */

  /**
   * Padded variant of AtomicLong supporting only raw accesses plus CAS. The value field is placed
   * between pads, hoping that the JVM doesn't reorder them.
   *
   * <p>JVM intrinsics note: It would be possible to use a release-only form of CAS here, if it were
   * provided.
   */
  static final class Cell {

    string.getChars(0, len, strCopy, 0);

    char[] array = new char[len * count];

    int strCopyLen = len;
    int pos = 0;
    while (count != 0) {
      if ((count & 1) != 0) {
        System.arraycopy(strCopy, 0, array, pos, strCopyLen);
        pos += strCopyLen;
      }
      count >>= 1;
      if (count != 0) {
        System.arraycopy(strCopy, 0, strCopy, strCopyLen, strCopyLen);

          break;
        }
        chars[pos - spread] = chars[pos];
        pos++;
      }
      spread++;
    }
    return new String(chars, 0, pos - spread);
  }

  /**
   * Returns a string containing all matching BMP characters of a character sequence, in order. For
   * example:
   *
   * <pre>{@code
   * CharMatcher.is('a').retainFrom("bazaar")
   * }</pre>
   *

      assertTrue(bb.remaining() < bufferSize);
      int before = processCalled;
      super.processRemaining(bb);
      int after = processCalled;
      assertEquals(before + 1, after); // default implementation pads and calls process()
      processCalled--; // don't count the tail invocation (makes tests a bit more understandable)
    }

    // ensures that the number of invocations looks sane

    int length = 0;
    for (char[] array : arrays) {
      length += array.length;
    }
    char[] result = new char[length];
    int pos = 0;
    for (char[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  /**
   * Returns a big-endian representation of {@code value} in a 2-element byte array; equivalent to