@Override
              public Sub apply(Sub sub) {
                return new ForwardingSub(sub);
              }
            });
  }

  interface Base {
    CharSequence getId();
  }

  interface Sub extends Base {
    @Override
    String getId();
  }

  private static class ForwardingSub implements Sub {
    private final Sub delegate;

    }
  }

  // TODO(benyu): migrate all subtyping tests from TypeTokenTest to this class using SubtypeTester.

  private interface Outdoor {}

  private interface Indoor {}

  private interface Grocery {}

  private interface Electronics {}

  private interface ConsumerFacing<T> {}

  private static class Mall<T> {
    class Shop<ProductT> {}

 * true or false value for a given input.
 *
 * <p>As this interface extends {@code java.util.function.Predicate}, an instance of this type may
 * be used as a {@code Predicate} directly. To use a {@code java.util.function.Predicate} where a
 * {@code com.google.common.base.Predicate} is expected, use the method reference {@code
 * predicate::test}.
 *
 * <p>This interface is now a legacy type. Use {@code java.util.function.Predicate} (or the

        interfaceMap);
  }

  private interface Interface1 {}

  private interface Interface2 {}

  private interface Interface3<T> extends Iterable<T> {}

  private interface Interface12 extends Interface1, Interface2 {}

  private static class Class1 implements Interface1 {}

  private static final class NoInterface {}

import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates queues, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestQueueGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  Queue<E> create(Object... elements);

 * parameters.
 *
 * @param <T> the type created by this generator.
 * @author George van den Driessche
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestSubjectGenerator<T extends @Nullable Object> {
  T createTestSubject();

import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates multisets, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestMultisetGenerator<E extends @Nullable Object>
    extends TestCollectionGenerator<E> {
  @Override
  Multiset<E> create(Object... elements);

class Promise<T extends @Nullable Object> implements IThenable<T> {

  @JsFunction
  interface PromiseExecutorCallbackFn<T extends @Nullable Object> {
    @JsFunction
    interface ResolveCallbackFn<T extends @Nullable Object> {
      void onInvoke(T value);
    }

    @JsFunction
    interface RejectCallbackFn {
      void onInvoke(Object error);
    }

 * "undo" it as best we can.
 */
@GwtCompatible
@Retention(RUNTIME)
@Target(TYPE)
@TypeQualifierDefault({FIELD, METHOD, PARAMETER})
@Nonnull

      throw new RuntimeException();
    }
  }

  private interface InterfaceStaticMethodFailsToCheckNull {
    static String create(String s) {
      return "I don't check";
    }
  }

  private interface InterfaceStaticMethodChecksNull {
    static String create(String s) {
      return checkNotNull(s);
    }
  }

  private interface InterfaceDefaultMethodFailsToCheckNull {