}
    return params;
  }

  private static final ImmutableSet<String> NOT_WORKING_ON_MOCKS =
      ImmutableSet.of("latestPermitAgeSec", "setRate", "getAvailablePermits");

  // We would use ArbitraryInstances, but it returns 0, invalid for many RateLimiter methods.
  private static final ImmutableClassToInstanceMap<Object> PARAMETER_VALUES =
      ImmutableClassToInstanceMap.builder()
          .put(int.class, 1)

  @J2ktIncompatible
  @GwtIncompatible // reflection
  @AndroidIncompatible // TODO(cpovirk): ClassNotFoundException: com.google.common.base.Function
  // (I suspect that this and the other similar failures happen with ArbitraryInstances proxies.)
  public void testEqualsAndSerializable() throws Exception {
    new ClassSanityTester().forAllPublicStaticMethods(Functions.class).testEqualsAndSerializable();
  }

  @J2ktIncompatible

    if (defaultValue != null) {
      return defaultValue;
    }
    @SuppressWarnings("unchecked") // All arbitrary instances are generics-safe
    T arbitrary = (T) ArbitraryInstances.get(type.getRawType());
    if (arbitrary != null) {
      return arbitrary;
    }
    if (type.getRawType() == Class.class) {
      // If parameter is Class<? extends Foo>, we return Foo.class

  }

  private <T> @Nullable T defaultGenerate(Class<T> rawType) {
    if (rawType.isInterface()) {
      // always create a new proxy
      return newProxy(rawType);
    }
    return ArbitraryInstances.get(rawType);
  }

  private <T> T newProxy(Class<T> interfaceType) {
    return Reflection.newProxy(interfaceType, new FreshInvocationHandler(interfaceType));
  }

  }

  private <T> @Nullable T defaultGenerate(Class<T> rawType) {
    if (rawType.isInterface()) {
      // always create a new proxy
      return newProxy(rawType);
    }
    return ArbitraryInstances.get(rawType);
  }

  private <T> T newProxy(Class<T> interfaceType) {
    return Reflection.newProxy(interfaceType, new FreshInvocationHandler(interfaceType));
  }