multimap.put("bar", 32);
                    multimap.put("foo", 16);
                    multimap = filterKeys(multimap, not(equalTo("foo")));
                    return filterKeys(multimap, not(equalTo("bar")));
                  }
                })
            .named("Multimaps.filterKeys[Multimaps.filterKeys[ListMultimap], Predicate]")
            .withFeatures(
                CollectionSize.ANY,

import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(Multimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
class FilteredKeyMultimap<K extends @Nullable Object, V extends @Nullable Object>

import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(Multimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
class FilteredKeyMultimap<K extends @Nullable Object, V extends @Nullable Object>

import com.google.common.base.Predicate;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(SetMultimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class FilteredKeySetMultimap<K extends @Nullable Object, V extends @Nullable Object>

import com.google.common.base.Predicate;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(SetMultimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class FilteredKeySetMultimap<K extends @Nullable Object, V extends @Nullable Object>

          throw new TimeoutException(
              "Timeout waiting for the services to become healthy. The "
                  + "following services have not started: "
                  + Multimaps.filterKeys(servicesByState, in(ImmutableSet.of(NEW, STARTING))));
        }
        checkHealthy();
      } finally {
        monitor.leave();
      }
    }

    void awaitStopped() {

  public static <K extends @Nullable Object, V extends @Nullable Object> Multimap<K, V> filterKeys(
      Multimap<K, V> unfiltered, Predicate<? super K> keyPredicate) {
    if (unfiltered instanceof SetMultimap) {
      return filterKeys((SetMultimap<K, V>) unfiltered, keyPredicate);
    } else if (unfiltered instanceof ListMultimap) {
      return filterKeys((ListMultimap<K, V>) unfiltered, keyPredicate);

  public static <K extends @Nullable Object, V extends @Nullable Object> Multimap<K, V> filterKeys(
      Multimap<K, V> unfiltered, Predicate<? super K> keyPredicate) {
    if (unfiltered instanceof SetMultimap) {
      return filterKeys((SetMultimap<K, V>) unfiltered, keyPredicate);
    } else if (unfiltered instanceof ListMultimap) {
      return filterKeys((ListMultimap<K, V>) unfiltered, keyPredicate);

              }
            }));
    assertEquals(newArrayList("a", "c", "e"), list);
  }

  // The Maps returned by Maps.filterEntries(), Maps.filterKeys(), and
  // Maps.filterValues() are not tested with removeIf() since Maps are not
  // Iterable.  Those returned by Iterators.filter() and Iterables.filter()
  // are not tested because they are unmodifiable.

              }
            }));
    assertEquals(newArrayList("a", "c", "e"), list);
  }

  // The Maps returned by Maps.filterEntries(), Maps.filterKeys(), and
  // Maps.filterValues() are not tested with removeIf() since Maps are not
  // Iterable.  Those returned by Iterators.filter() and Iterables.filter()
  // are not tested because they are unmodifiable.