byte result = 0x01;
    // Trick the JVM to prevent it from using the hash function non-polymorphically
    result ^= Hashing.crc32().hashInt(reps).asBytes()[0];
    result ^= Hashing.adler32().hashInt(reps).asBytes()[0];
    for (int i = 0; i < reps; i++) {
      result ^= hashFunction.hashBytes(testBytes).asBytes()[0];
    }
    return result;
  }

    byte result = 0x01;
    // Trick the JVM to prevent it from using the hash function non-polymorphically
    result ^= Hashing.crc32().hashInt(reps).asBytes()[0];
    result ^= Hashing.adler32().hashInt(reps).asBytes()[0];
    for (int i = 0; i < reps; i++) {
      result ^= hashFunction.hashBytes(testBytes).asBytes()[0];
    }
    return result;
  }

        Hashing.md5().bits() + Hashing.md5().bits(),
        Hashing.concatenating(Hashing.md5(), Hashing.md5()).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits(),
        Hashing.concatenating(Hashing.md5(), Hashing.murmur3_32()).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits() + Hashing.murmur3_128().bits(),

        Hashing.md5().bits() + Hashing.md5().bits(),
        Hashing.concatenating(Hashing.md5(), Hashing.md5()).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits(),
        Hashing.concatenating(Hashing.md5(), Hashing.murmur3_32()).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits() + Hashing.murmur3_128().bits(),

   * specific length.
   *
   * <p>For example, if you need 1024-bit hash codes, you could join two {@link Hashing#sha512} hash
   * functions together: {@code Hashing.concatenating(Hashing.sha512(), Hashing.sha512())}.
   *
   * @since 19.0
   */
  public static HashFunction concatenating(
      HashFunction first, HashFunction second, HashFunction... rest) {

## Die Passwörter hashen und überprüfen

Importieren Sie die benötigten Tools aus `passlib`.

Erstellen Sie einen PassLib-„Kontext“. Der wird für das Hashen und Verifizieren von Passwörtern verwendet.

!!! tip "Tipp"
    Der PassLib-Kontext kann auch andere Hashing-Algorithmen verwenden, einschließlich deprecateter Alter, um etwa nur eine Verifizierung usw. zu ermöglichen.

    assertEquals(
        "Hashing.hmacMd5(Key[algorithm=HmacMD5, format=RAW])", Hashing.hmacMd5(MD5_KEY).toString());
    assertEquals(
        "Hashing.hmacMd5(Key[algorithm=HmacMD5, format=RAW])", Hashing.hmacMd5(keyData).toString());

    assertEquals(
        "Hashing.hmacSha1(Key[algorithm=HmacSHA1, format=RAW])",
        Hashing.hmacSha1(SHA1_KEY).toString());
    assertEquals(

 * average, in the marking phase, not {@code 5.0} as in {@code java.util.HashSet}.
 *
 * <p>If there are no removals, then {@link #iterator iteration} order is the same as insertion
 * order. Any removal invalidates any ordering guarantees.
 *
 * <p>This class should not be assumed to be universally superior to {@code java.util.HashSet}.
 * Generally speaking, this class reduces object allocation and memory consumption at the price of

    assertEquals("Hashing.md5()", Hashing.md5().toString());
    assertEquals("Hashing.sha1()", Hashing.sha1().toString());
    assertEquals("Hashing.sha256()", Hashing.sha256().toString());
    assertEquals("Hashing.sha512()", Hashing.sha512().toString());
  }

  private static void assertMessageDigestHashing(byte[] input, String algorithmName) {
    try {
      MessageDigest digest = MessageDigest.getInstance(algorithmName);

 * average, in the marking phase, not {@code 5.0} as in {@code java.util.HashSet}.
 *
 * <p>If there are no removals, then {@link #iterator iteration} order is the same as insertion
 * order. Any removal invalidates any ordering guarantees.
 *
 * <p>This class should not be assumed to be universally superior to {@code java.util.HashSet}.
 * Generally speaking, this class reduces object allocation and memory consumption at the price of