* "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#maps">{@code Maps}</a>.
 *
 * @author Kevin Bourrillion
 * @author Mike Bostock
 * @author Isaac Shum
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public final class Maps {
  private Maps() {}

  private enum EntryFunction implements Function<Entry<?, ?>, @Nullable Object> {

                    Map<String, String> map = Maps.newHashMap();
                    putEntries(map, entries);
                    map.putAll(ENTRIES_TO_FILTER);
                    map = Maps.filterEntries(map, FILTER_ENTRIES_1);
                    return Maps.filterEntries(map, FILTER_ENTRIES_2);
                  }
                })
            .named("Maps.filterEntries[Maps.filterEntries[Map, Predicate], Predicate]")

    assertEquals(Maps.immutableEntry("foo", 5), entryIterator.next());
    assertEquals(Maps.immutableEntry("bar", 4), entryIterator.next());
    assertEquals(Maps.immutableEntry("foo", 3), entryIterator.next());
    assertEquals(Maps.immutableEntry("cow", 2), entryIterator.next());
    assertEquals(Maps.immutableEntry("bar", 1), entryIterator.next());

    Map<C, V> row = Maps.safeGet(rowMap(), rowKey);
    return row != null && Maps.safeContainsKey(row, columnKey);
  }

  @Override
  @CheckForNull
  public V get(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {
    Map<C, V> row = Maps.safeGet(rowMap(), rowKey);
    return (row == null) ? null : Maps.safeGet(row, columnKey);
  }

  @Override

/**
 * An object representing the differences between two maps.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@DoNotMock("Use Maps.difference")
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface MapDifference<K extends @Nullable Object, V extends @Nullable Object> {
  /**
   * Returns {@code true} if there are no differences between the two maps; that is, if the maps are
   * equal.
   */
  boolean areEqual();

import java.util.Map;

/**
 * Tests for {@link Maps#transformValues(Map, Function)}.
 *
 * @author Isaac Shum
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class MapsTransformValuesTest extends AbstractMapsTransformValuesTest {
  @Override
  protected Map<String, String> makeEmptyMap() {
    return Maps.transformValues(Maps.<String, String>newHashMap(), Functions.<String>identity());
  }

    assertFalse(entries.remove((Object) 4.5));
    assertFalse(entries.contains(Maps.immutableEntry("foo", Collections.singletonList(1))));
    assertFalse(entries.remove(Maps.immutableEntry("foo", Collections.singletonList(1))));
    assertFalse(entries.contains(Maps.immutableEntry("foo", Sets.newLinkedHashSet(asList(1, 2)))));
    assertFalse(entries.remove(Maps.immutableEntry("foo", Sets.newLinkedHashSet(asList(1, 2)))));

    assertThat(map.entrySet())
        .containsExactly(Maps.immutableEntry("one", 1), Maps.immutableEntry("three", 3))
        .inOrder();
  }

  public void testHeadMapExclusive() {
    Map<String, Integer> map =
        ImmutableSortedMap.of("one", 1, "two", 2, "three", 3).headMap("three", false);
    assertThat(map.entrySet()).containsExactly(Maps.immutableEntry("one", 1));
  }

        return obj != null && removeFromColumnIf(Maps.<V>valuePredicateOnEntries(equalTo(obj)));
      }

      @Override
      public boolean removeAll(final Collection<?> c) {
        return removeFromColumnIf(Maps.<V>valuePredicateOnEntries(in(c)));
      }

      @Override
      public boolean retainAll(final Collection<?> c) {
        return removeFromColumnIf(Maps.<V>valuePredicateOnEntries(not(in(c))));
      }

        ImmutableList.of(
            Maps.immutableEntry("foo", 99),
            Maps.immutableEntry("foo", 88),
            Maps.immutableEntry("bar", 77));

    for (final int startIndex : new int[] {0, 3, 5}) {
      List<Entry<String, Integer>> list =
          Lists.newArrayList(
              Maps.immutableEntry("foo", 2),
              Maps.immutableEntry("foo", 3),