`UnmodifiableMultimap.forEach` uses the `Multimap.forEach` default implementation which involves listing entries, and creating a new lambda instead of simply passing the BiConsumer through to the protected instance. This is safe to pass directly though because `forEach(BiConsumer)` is a read-only operation.
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.SortedSet;
import java.util.Spliterator;
import java.util.function.BiConsumer;
import java.util.function.Consumer;
import java.util.stream.Collector;
import java.util.stream.Stream;
import org.checkerframework.checker.nullness.qual.Nullable;
/**
 * Provides static methods acting on or generating a {@code Multimap}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#multimaps"> {@code
 * Multimaps}</a>.
 *
 * @author Jared Levy
 * @author Robert Konigsberg
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible(emulated = true)