}
    return fromHashers(hashers);
  }

  private Hasher fromHashers(Hasher[] hashers) {
    return new Hasher() {
      @Override
      public Hasher putByte(byte b) {
        for (Hasher hasher : hashers) {
          hasher.putByte(b);
        }
        return this;
      }

      @Override
      public Hasher putBytes(byte[] bytes) {
        for (Hasher hasher : hashers) {
          hasher.putBytes(bytes);
        }

    Random random = new Random(0);
    for (int i = 0; i < 200; i++) {
      RandomHasherAction.pickAtRandom(random).performAction(random, hashers);
    }
    HashCode[] codes = new HashCode[hashers.size()];
    for (int i = 0; i < hashers.size(); i++) {
      codes[i] = hashers.get(i).hash();
    }
    for (int i = 1; i < codes.length; i++) {
      assertEquals(codes[i - 1], codes[i]);
    }
  }

            function.bits(),
            function);
      }
    }

    @Override
    HashCode makeHash(Hasher[] hashers) {
      byte[] bytes = new byte[bits() / 8];
      int i = 0;
      for (Hasher hasher : hashers) {
        HashCode newHash = hasher.hash();
        i += newHash.writeBytesTo(bytes, i, newHash.bits() / 8);
      }
      return HashCode.fromBytesNoCopy(bytes);
    }

}

// Borrow a single hasher.
func (h *HashBorrower) Borrow() hash.Hash {
	hasher := h.pool.Get()
	h.borrowed = append(h.borrowed, hasher)
	hasher.Reset()
	return hasher
}

// ReturnAll will return all borrowed hashes.
func (h *HashBorrower) ReturnAll() {
	for _, hasher := range h.borrowed {
		h.pool.Put(hasher)
	}
	h.borrowed = nil
}

// StandardClaims are basically standard claims with "accessKey"

 * @since 11.0
 */
@Beta
public interface Hasher extends PrimitiveSink {
  @CanIgnoreReturnValue
  @Override
  Hasher putByte(byte b);

  @CanIgnoreReturnValue
  @Override
  Hasher putBytes(byte[] bytes);

  @CanIgnoreReturnValue
  @Override
  Hasher putBytes(byte[] bytes, int off, int len);

  @CanIgnoreReturnValue
  @Override
  Hasher putBytes(ByteBuffer bytes);

  @CanIgnoreReturnValue

    Random random2 = new Random(2L);
    Hasher hasher1 = hashFunction.newHasher();
    Hasher hasher2 = hashFunction.newHasher();
    for (int i = 0; i < numActions; i++) {
      RandomHasherAction.pickAtRandom(random1).performAction(random1, ImmutableSet.of(hasher1));
      RandomHasherAction.pickAtRandom(random2).performAction(random2, ImmutableSet.of(hasher2));
    }

    Assert.assertEquals(expected1, hasher1.hash());

 *       cryptographic hashes.)
 *   <li><b>fast:</b> perhaps self-explanatory, but often the most important consideration.
 * </ul>
 *
 * <h3>Providing input to a hash function</h3>
 *
 * <p>The primary way to provide the data that your hash function should act on is via a {@link
 * Hasher}. Obtain a new hasher from the hash function using {@link #newHasher}, "push" the relevant

 *
 * @author Qian Huang
 * @since 16.0
 */
@Beta
public final class HashingInputStream extends FilterInputStream {
  private final Hasher hasher;

  /**
   * Creates an input stream that hashes using the given {@link HashFunction} and delegates all data
   * read from it to the underlying {@link InputStream}.
   *

  @Override
  @CanIgnoreReturnValue
  public final Hasher putByte(byte b) {
    buffer.put(b);
    munchIfFull();
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putShort(short s) {
    buffer.putShort(s);
    munchIfFull();
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putChar(char c) {
    buffer.putChar(c);

 *
 * @author Zoe Piepmeier
 * @since 16.0
 */
@Beta
public final class HashingOutputStream extends FilterOutputStream {
  private final Hasher hasher;

  /**
   * Creates an output stream that hashes using the given {@link HashFunction}, and forwards all
   * data written to it to the underlying {@link OutputStream}.
   *