*
   * <p><b>Discouraged:</b> Prefer using a lambda like {@code v -> v}, which is shorter and often
   * more readable.
   */
  // implementation is "fully variant"; E has become a "pass-through" type
  @SuppressWarnings("unchecked")
  public static <E extends @Nullable Object> Function<E, E> identity() {
    return (Function<E, E>) IdentityFunction.INSTANCE;
  }

  // enum singleton pattern

  @SuppressWarnings("CatchingUnchecked") // sneaky checked exception
  public void addListener(Runnable listener, Executor executor) {
    checkNotNull(listener, "Runnable was null.");
    checkNotNull(executor, "Executor was null.");
    try {
      executor.execute(listener);
    } catch (Exception e) { // sneaky checked exception
      // ListenableFuture's contract is that it will not throw unchecked exceptions, so log the bad

    public Set<Multiset.Entry<E>> create(Object... entries) {
      List<Object> contents = new ArrayList<>();
      Set<E> elements = new HashSet<>();
      for (Object o : entries) {
        @SuppressWarnings("unchecked")
        Multiset.Entry<E> entry = (Entry<E>) o;
        checkArgument(
            elements.add(entry.getElement()), "Duplicate keys not allowed in EntrySetGenerator");
        for (int i = 0; i < entry.getCount(); i++) {

import java.util.HashSet;
import java.util.Set;

public class AcceptedRegressionsRulePostProcess implements PostProcessViolationsRule {

    @Override
    @SuppressWarnings("unchecked")
    public void execute(ViolationCheckContextWithViolations context) {
        Set<ApiChange> acceptedApiChanges = (Set<ApiChange>) context.getUserData().get("acceptedApiChanges");

   *
   * <p><b>Discouraged:</b> Prefer using a lambda like {@code v -> v}, which is shorter and often
   * more readable.
   */
  // implementation is "fully variant"; E has become a "pass-through" type
  @SuppressWarnings("unchecked")
  public static <E extends @Nullable Object> Function<E, E> identity() {
    return (Function<E, E>) IdentityFunction.INSTANCE;
  }

  // enum singleton pattern

    JAPAN,
    SWITZERLAND,
    UK
  }

  @AndroidIncompatible // test-suite builders
  public static final class EnumBiMapGenerator implements TestBiMapGenerator<Country, Currency> {
    @SuppressWarnings("unchecked")
    @Override
    public BiMap<Country, Currency> create(Object... entries) {
      BiMap<Country, Currency> result = EnumBiMap.create(Country.class, Currency.class);
      for (Object object : entries) {

  public <S extends @Nullable T> Ordering<S> reverse() {
    // ordering.reverse() might be optimized, so let it do its thing
    return ordering.<T>reverse().<@NonNull S>nullsLast();
  }

  @SuppressWarnings("unchecked") // still need the right way to explain this
  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsFirst() {
    return (Ordering<@Nullable S>) this;
  }

  @Override

  }

  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsFirst() {
    return ordering.<@NonNull S>nullsFirst();
  }

  @SuppressWarnings("unchecked") // still need the right way to explain this
  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsLast() {
    return (Ordering<@Nullable S>) this;
  }

  @Override

  }

  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsFirst() {
    return ordering.<@NonNull S>nullsFirst();
  }

  @SuppressWarnings("unchecked") // still need the right way to explain this
  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsLast() {
    return (Ordering<@Nullable S>) this;
  }

  @Override

 * This implementation passes the navigable map test suites.
 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeMap<K, V> implements Serializable, NavigableMap<K, V> {
  @SuppressWarnings("unchecked")
  private static final Comparator<Object> NATURAL_ORDER =
      (o1, o2) -> ((Comparable<Object>) o1).compareTo(o2);

  private final NavigableMap<K, V> delegate;

  public SafeTreeMap() {