FreshValueGenerator paramValues = new FreshValueGenerator();
    List<@Nullable Object> passedArgs = Lists.newArrayList();
    for (Class<?> paramType : method.getParameterTypes()) {
      passedArgs.add(paramValues.generateFresh(paramType));
    }
    return passedArgs.toArray();
  }

  /** Tests a single interaction against a method. */
  private static final class InteractionTester<T> extends AbstractInvocationHandler {

    FreshValueGenerator paramValues = new FreshValueGenerator();
    List<@Nullable Object> passedArgs = Lists.newArrayList();
    for (Class<?> paramType : method.getParameterTypes()) {
      passedArgs.add(paramValues.generateFresh(paramType));
    }
    return passedArgs.toArray();
  }

  /** Tests a single interaction against a method. */
  private static final class InteractionTester<T> extends AbstractInvocationHandler {

   * </ul>
   */
  final @Nullable Object generateFresh(TypeToken<?> type) {
    Object generated = generate(type);
    if (generated != null) {
      freshness.incrementAndGet();
    }
    return generated;
  }

  final <T> @Nullable T generateFresh(Class<T> type) {
    return Primitives.wrap(type).cast(generateFresh(TypeToken.of(type)));
  }

   * </ul>
   */
  final @Nullable Object generateFresh(TypeToken<?> type) {
    Object generated = generate(type);
    if (generated != null) {
      freshness.incrementAndGet();
    }
    return generated;
  }

  final <T> @Nullable T generateFresh(Class<T> type) {
    return Primitives.wrap(type).cast(generateFresh(TypeToken.of(type)));
  }

    tester.addEqualityGroup(instance, createInstance(factory, equalArgs));
    for (int i = 0; i < params.size(); i++) {
      List<Object> newArgs = Lists.newArrayList(args);
      Object newArg = argGenerators.get(i).generateFresh(params.get(i).getType());

      if (newArg == null || Objects.equal(args.get(i), newArg)) {
        if (params.get(i).getType().getRawType().isEnum()) {