* @return the merged node
     */
    @Nullable
    static XmlNode merge(@Nullable XmlNode dominant, @Nullable XmlNode recessive) {
        return merge(dominant, recessive, null);
    }

    @Nullable
    static XmlNode merge(
            @Nullable XmlNode dominant, @Nullable XmlNode recessive, @Nullable Boolean childMergeOverride) {
        if (recessive == null) {
            return dominant;
        }

            return Lists.transform(objs, OPTIONAL_TO_NULLABLE);
          }
        });
  }

  private CacheBuilder<Object, Object> createCacheBuilder(
      @Nullable Integer concurrencyLevel,
      @Nullable Integer initialCapacity,
      @Nullable Integer maximumSize,
      @Nullable DurationSpec expireAfterWrite,
      @Nullable DurationSpec expireAfterAccess,
      @Nullable DurationSpec refresh,

  }

  static <R extends @Nullable Object, C extends @Nullable Object, V extends @Nullable Object>
      Table<R, C, V> table(Table<R, C, V> table, @CheckForNull Object mutex) {
    return new SynchronizedTable<>(table, mutex);
  }

  static final class SynchronizedTable<
          R extends @Nullable Object, C extends @Nullable Object, V extends @Nullable Object>

                return (from == null) ? true : null;
              }
            });

    Set<Entry<@Nullable String, @Nullable Boolean>> entries = map.entrySet();
    assertTrue(entries.contains(Maps.immutableEntry("a", true)));
    assertTrue(entries.contains(Maps.<String, @Nullable Boolean>immutableEntry("b", null)));
    assertTrue(

import java.util.List;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@code GeneralRange}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class GeneralRangeTest extends TestCase {
  private static final Ordering<@Nullable Integer> ORDERING =
      Ordering.<Integer>natural().<Integer>nullsFirst();

    return super.containsAll(collection);
  }

  @Override
  public Iterator<E> iterator() {
    return Arrays.asList(contents).iterator();
  }

  @Override
  public @Nullable Object[] toArray() {
    @Nullable Object[] result = new @Nullable Object[contents.length];
    System.arraycopy(contents, 0, result, 0, contents.length);
    return result;
  }

  /*

    TreeMultimap<@Nullable String, @Nullable Integer> multimap = createPopulate();
    assertThat(multimap.entries())
        .containsExactly(
            Maps.<@Nullable String, Integer>immutableEntry(null, 7),
            Maps.<@Nullable String, Integer>immutableEntry(null, 3),
            Maps.<@Nullable String, Integer>immutableEntry(null, 1),
            Maps.<String, @Nullable Integer>immutableEntry("tree", null),

    }

    @Override
    public @Nullable Entry<K, V> firstEntry() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate().firstEntry();
    }

    @Override
    public @Nullable Entry<K, V> floorEntry(K key) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate().floorEntry(key);
    }

    @Override
    public @Nullable K floorKey(K key) {

  @GwtCompatible(serializable = true)
  public static <T extends @Nullable Object> Predicate<T> alwaysTrue() {
    return ObjectPredicate.ALWAYS_TRUE.withNarrowedType();
  }

  /** Returns a predicate that always evaluates to {@code false}. */
  @GwtCompatible(serializable = true)
  public static <T extends @Nullable Object> Predicate<T> alwaysFalse() {
    return ObjectPredicate.ALWAYS_FALSE.withNarrowedType();
  }

            Tables.<@Nullable Object, @Nullable Object, @Nullable Object>immutableCell(
                null, null, null))
        .addEqualityGroup(
            Tables.<String, @Nullable Object, @Nullable Object>immutableCell("bar", null, null))
        .addEqualityGroup(
            Tables.<@Nullable Object, Integer, @Nullable Object>immutableCell(null, 2, null))
        .addEqualityGroup(