* Null row keys, columns keys, and values are not supported.
 *
 * <p>Lookups by row key are often faster than lookups by column key, because the data is stored in
 * a {@code Map<R, Map<C, V>>}. A method call like {@code column(columnKey).get(rowKey)} still runs
 * quickly, since the row key is provided. However, {@code column(columnKey).size()} takes longer,

    /**
     * Associates {@code key} with {@code value} in the built map. Duplicate keys are not allowed,
     * and will cause {@link #build} to fail.
     */
    @CanIgnoreReturnValue
    public <T extends B> Builder<B> put(Class<T> key, T value) {
      mapBuilder.put(key, value);
      return this;
    }

    /**
     * Associates all of {@code map's} keys and values in the built map. Duplicate keys are not

    }

    @Override
    public Collection<V> get(@ParametricNullness K key) {
      return unmodifiableValueCollection(delegate.get(key));
    }

    @Override
    public Multiset<K> keys() {
      Multiset<K> result = keys;
      if (result == null) {
        keys = result = Multisets.unmodifiableMultiset(delegate.keys());
      }
      return result;
    }

    @Override

    }

    @Override
    public Collection<V> get(@ParametricNullness K key) {
      return unmodifiableValueCollection(delegate.get(key));
    }

    @Override
    public Multiset<K> keys() {
      Multiset<K> result = keys;
      if (result == null) {
        keys = result = Multisets.unmodifiableMultiset(delegate.keys());
      }
      return result;
    }

    @Override

    return delegate().getAll(keys);
  }

  @Override
  public V apply(K key) {
    return delegate().apply(key);
  }

  @Override
  public void refresh(K key) {
    delegate().refresh(key);
  }

  /**
   * A simplified version of {@link ForwardingLoadingCache} where subclasses can pass in an already
   * constructed {@link LoadingCache} as the delegate.

                for (KerberosKey key : keys) {
                    keysByAlgo.put(key.getKeyType(), key);
                }

                KerberosKey serverKey = keysByAlgo.get(encType.getValue().intValue());
                if (keysByAlgo.isEmpty() || serverKey == null) {
                    throw new PACDecodingException("Kerberos key not found for eType " + encType.getValue());
                }

    /** Storage endpoint configuration key. */
    public static final String STORAGE_ENDPOINT = "storage.endpoint";

    /** Storage access key configuration key. */
    public static final String STORAGE_ACCESS_KEY = "storage.accesskey";

    /** Storage secret key configuration key. */
    public static final String STORAGE_SECRET_KEY = "storage.secretkey";

    assertEmpty(multimap().entries());
    assertEmpty(multimap().asMap());
    assertEmpty(multimap().keySet());
    assertEmpty(multimap().keys());
    assertEmpty(multimap().values());
    for (K key : sampleKeys()) {
      assertGet(key);
    }
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClear() {
    multimap().clear();
    assertCleared();
  }

 * interface. It does not permit null keys or values.
 *
 * <p><b>Note:</b> by default, the returned map uses equality comparisons (the {@link Object#equals
 * equals} method) to determine equality for keys or values. However, if {@link #weakKeys} was
 * specified, the map uses identity ({@code ==}) comparisons instead for keys. Likewise, if {@link

   * Multimap#asMap} view determines the ordering in which data is written to the stream.
   *
   * <p>The serialized output consists of the number of distinct keys, and then for each distinct
   * key: the key, the number of values for that key, and the key's values.
   */
  static <K extends @Nullable Object, V extends @Nullable Object> void writeMultimap(