Hasher hasher = HASH_FN.newHasher();
    // Expected data is 0x0100010100000000
    hasher
        .putBoolean(true)
        .putBoolean(true)
        .putBoolean(false)
        .putBoolean(true)
        .putBoolean(false)
        .putBoolean(false)
        .putBoolean(false)
        .putBoolean(false);
    long hashCode = hasher.hash().asLong();

    hasher = HASH_FN.newHasher();
    hasher

    Hasher hasher = HASH_FN.newHasher();
    // Expected data is 0x0100010100000000
    hasher
        .putBoolean(true)
        .putBoolean(true)
        .putBoolean(false)
        .putBoolean(true)
        .putBoolean(false)
        .putBoolean(false)
        .putBoolean(false)
        .putBoolean(false);
    long hashCode = hasher.hash().asLong();

    hasher = HASH_FN.newHasher();
    hasher

 *
 * @author Dimitris Andreou
 */
abstract class AbstractHasher implements Hasher {
  @Override
  @CanIgnoreReturnValue
  public final Hasher putBoolean(boolean b) {
    return putByte(b ? (byte) 1 : (byte) 0);
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putDouble(double d) {
    return putLong(Double.doubleToRawLongBits(d));
  }

  /** Puts a double into this sink. */
  @CanIgnoreReturnValue
  PrimitiveSink putDouble(double d);

  /** Puts a boolean into this sink. */
  @CanIgnoreReturnValue
  PrimitiveSink putBoolean(boolean b);

  /** Puts a character into this sink. */
  @CanIgnoreReturnValue
  PrimitiveSink putChar(char c);

  /**
   * Puts each 16-bit code unit from the {@link CharSequence} into this sink.
   *

  @CanIgnoreReturnValue
  @Override
  Hasher putDouble(double d);

  /** Equivalent to {@code putByte(b ? (byte) 1 : (byte) 0)}. */
  @CanIgnoreReturnValue
  @Override
  Hasher putBoolean(boolean b);

  @CanIgnoreReturnValue
  @Override
  Hasher putChar(char c);

  /**
   * Equivalent to processing each {@code char} value in the {@code CharSequence}, in order. In