* 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) {

    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);

    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(

    String init = "d41d8cd98f00b204e9800998ecf8427e";
    assertEquals(init, Hashing.md5().newHasher().hash().toString());

    String asciiHash = "e5df5a39f2b8cb71b24e1d8038f93131";
    assertEquals(asciiHash, Files.hash(asciiFile, Hashing.md5()).toString());

    String i18nHash = "7fa826962ce2079c8334cd4ebf33aea4";
    assertEquals(i18nHash, Files.hash(i18nFile, Hashing.md5()).toString());
  }

  public void testMap() throws IOException {

  }

  @Override
  public boolean contains(@CheckForNull Object target) {
    @Nullable Object[] table = this.table;
    if (target == null || table.length == 0) {
      return false;
    }
    for (int i = Hashing.smearedHash(target); ; i++) {
      i &= mask;
      Object candidate = table[i];
      if (candidate == null) {
        return false;
      } else if (candidate.equals(target)) {
        return true;
      }

 *
 */
public interface MetadataReader {

    /**
     * The key for the option to enable strict parsing. This option is of type {@link Boolean} and defaults to {@code
     * true}. If {@code false}, unknown elements will be ignored instead of causing a failure.
     */
    String IS_STRICT = "org.apache.maven.artifact.repository.metadata.io.isStrict";

    /**

import com.google.common.base.Charsets;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.hash.Hashing;
import com.google.common.io.Closer.LoggingSuppressor;
import com.google.common.primitives.UnsignedBytes;
import com.google.common.testing.TestLogHandler;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

      addressAsLong = ByteBuffer.wrap(ip6.getAddress(), 0, 8).getLong();
    }

    // Many strategies for hashing are possible. This might suffice for now.
    int coercedHash = Hashing.murmur3_32_fixed().hashLong(addressAsLong).asInt();

    // Squash into 224/4 Multicast and 240/4 Reserved space (i.e. 224/3).
    coercedHash |= 0xe0000000;

 *     class (such as {@link #named}) return this type, so that Builder methods of more derived
 *     classes can be chained onto them without casting.
 * @param <G> The type of the generator to be passed to testers in the generated test suite. An
 *     instance of G should somehow provide an instance of the class under test, plus any other

    // This will be caught by getAll(), causing it to fall back to multiple calls to
    // LoadingCache.get
    throw new UnsupportedLoadingOperationException();
  }

  /**
   * Returns a cache loader that uses {@code function} to load keys, without supporting either
   * reloading or bulk loading. This allows creating a cache loader using a lambda expression.
   *