* key. A {@link HashMap} associates each key with an {@link ArrayList} of values.
 *
 * <p>When iterating through the collections supplied by this class, the ordering of values for a
 * given key agrees with the order in which the values were added.
 *
 * <p>This multimap allows duplicate key-value pairs. After adding a new key-value pair equal to an

  /** Discards any cached value for key {@code key}. */
  void invalidate(@CompatibleWith("K") Object key);

  /**
   * Discards any cached values for keys {@code keys}.
   *
   * @since 11.0
   */
  // For discussion of <? extends Object>, see getAllPresent.
  void invalidateAll(Iterable<? extends Object> keys);

  /** Discards all entries in the cache. */
  void invalidateAll();

      return;
    }

    Set<K> keys = map.keySet();
    K key = keys.iterator().next();
    if (supportsRemove) {
      int initialSize = map.size();
      keys.remove(key);
      assertEquals(initialSize - 1, map.size());
      assertFalse(map.containsKey(key));
    } else {
      assertThrows(UnsupportedOperationException.class, () -> keys.remove(key));
    }
    assertInvariants(map);
  }

   * key-value pairs are added to the multimap.
   *
   * @param key key to associate with values in the collection
   * @return a new decorated set containing a collection of values for one key
   */
  @Override
  Collection<V> createCollection(@ParametricNullness K key) {
    return new ValueSet(key, valueSetCapacity);
  }

  /**
   * {@inheritDoc}
   *

  Multiset<K> createKeys() {
    return new Keys();
  }

  @WeakOuter
  final class Keys extends Multimaps.Keys<K, V> {
    Keys() {
      super(FilteredEntryMultimap.this);
    }

    @Override
    public int remove(@Nullable Object key, int occurrences) {
      checkNonnegative(occurrences, "occurrences");
      if (occurrences == 0) {
        return count(key);
      }

        valuesBuilder.add(value);
      }
      return this;
    }

    /**
     * Stores an array of values with the same key in the built multimap.
     *
     * @throws NullPointerException if the key or any value is null. The builder is left in an
     *     invalid state.
     */
    @CanIgnoreReturnValue
    public Builder<K, V> putAll(K key, V... values) {

  }

  /**
   * Returns a hash table for the specified keys and values, and ensures that neither keys nor
   * values are null. This method may update {@code alternatingKeysAndValues} if there are duplicate
   * keys. If so, the return value will indicate how many entries are still valid, and will also
   * include a {@link Builder.DuplicateKey} in case duplicate keys are not allowed now or will not

      keys.remove(1);
      keys.remove(2);
      assertFalse(keys.remove(null));
      assertFalse(keys.remove(6));
      assertFalse(keys.remove(-6));
      assertFalse(keys.removeAll(asList(null, 0, 15, 1500)));
      assertFalse(keys.retainAll(asList(null, 0, 15, 1500)));
      checkEmpty(keys);
      checkEmpty(cache);
    }
  }

        # String columns may not be needed
        # to be set these condition-keys basically.
        #; GreaterThan = map:{}
        #; LessThan = map:{}
        #; GreaterEqual = map:{}
        #; LessEqual = map:{}

        # [Exclude]
        # Common columns of String type may not be needed
        # to be set these condition-keys basically.
        #; !NotEqual = map:{ $$ALL$$ = list:{ $$CommonColumn$$ } }

 * 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,