public void testFrequency_multiset() {
    Multiset<String> multiset = ImmutableMultiset.of("a", "b", "a", "c", "b", "a");
    assertEquals(3, frequency(multiset, "a"));
    assertEquals(2, frequency(multiset, "b"));
    assertEquals(1, frequency(multiset, "c"));
    assertEquals(0, frequency(multiset, "d"));
    assertEquals(0, frequency(multiset, 4.2));
    assertEquals(0, frequency(multiset, null));
  }

import static java.util.Arrays.asList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionSize;
import org.junit.Ignore;

/**
 * Tests for {@code Multiset.containsAll} not already addressed by {@code CollectionContainsTester}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

    // targets.size() < size() / log(size())
    // TODO(kevinb): see if we can share code with OrderedIterator after it
    // graduates from labs.
    if (targets instanceof Multiset) {
      targets = ((Multiset<?>) targets).elementSet();
    }
    if (!SortedIterables.hasSameComparator(comparator(), targets) || (targets.size() <= 1)) {
      return super.containsAll(targets);
    }

    /*

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionFeature;
import java.util.Collections;
import org.junit.Ignore;

/**
 * Tests for {@code Multiset.add}.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionFeature;
import java.util.Collections;
import org.junit.Ignore;

/**
 * Tests for {@code Multiset.add}.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

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

  @Override
  public boolean isEmpty() {
    return delegate().isEmpty();
  }

  @Override
  public Multiset<K> keys() {
    return delegate().keys();
  }

  @Override
  public Set<K> keySet() {
    return delegate().keySet();
  }

  @CanIgnoreReturnValue
  @Override

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

  @Override
  public boolean isEmpty() {
    return delegate().isEmpty();
  }

  @Override
  public Multiset<K> keys() {
    return delegate().keys();
  }

  @Override
  public Set<K> keySet() {
    return delegate().keySet();
  }

  @CanIgnoreReturnValue
  @Override

 *
 * <p><b>Note:</b> If your values are always positive and less than 2^31, you may wish to use a
 * {@link com.google.common.collect.Multiset} such as {@link
 * com.google.common.collect.ConcurrentHashMultiset} instead.
 *
 * <p><b>Warning:</b> Unlike {@code Multiset}, entries whose values are zero are not automatically
 * removed from the map. Instead they must be removed manually with {@link #removeAllZeros}.
 *

import com.google.common.collect.LinkedHashMultiset;
import com.google.common.collect.ListMultimap;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multiset;
import com.google.common.collect.Ordering;
import com.google.common.collect.Range;
import com.google.common.collect.RowSortedTable;
import com.google.common.collect.SetMultimap;

        Set<String> set,
        ImmutableSet<Integer> immutableSet,
        SortedSet<Number> sortedSet,
        ImmutableSortedSet<Number> immutableSortedSet,
        Multiset<String> multiset,
        ImmutableMultiset<Integer> immutableMultiset,
        Multimap<String, Integer> multimap,
        ImmutableMultimap<String, Integer> immutableMultimap,
        Table<String, Integer, Exception> table,