} else {
        Type[] upperBounds = wildcard.getUpperBounds();
        checkArgument(upperBounds.length == 1, "Wildcard should have only one upper bound.");
        return subtypeOf(newArrayType(upperBounds[0]));
      }
    }
    return JavaVersion.CURRENT.newArrayType(componentType);
  }

  /**
   * Returns a type where {@code rawType} is parameterized by {@code arguments} and is owned by

  /**
   * Returns a predicate that evaluates to {@code true} if the class being tested is assignable to
   * (is a subtype of) {@code clazz}. Example:
   *
   * {@snippet :
   * List<Class<?>> classes = Arrays.asList(Object.class, String.class, Number.class, Long.class);
   * return Iterables.filter(classes, subtypeOf(Number.class));
   * }
   *

  /**
   * Returns a predicate that evaluates to {@code true} if the class being tested is assignable to
   * (is a subtype of) {@code clazz}. Example:
   *
   * {@snippet :
   * List<Class<?>> classes = Arrays.asList(Object.class, String.class, Number.class, Long.class);
   * return Iterables.filter(classes, subtypeOf(Number.class));
   * }
   *

    assertThrows(IllegalArgumentException.class, () -> Types.subtypeOf(int.class));
  }

  public void testNewWildcardType_serializable() {
    SerializableTester.reserializeAndAssert(Types.supertypeOf(String.class));
    SerializableTester.reserializeAndAssert(Types.subtypeOf(String.class));
    SerializableTester.reserializeAndAssert(Types.subtypeOf(Object.class));
  }

    assertEquals(
        Types.subtypeOf(Object.class),
        TypeToken.of(Types.subtypeOf(Object[].class)).getComponentType().getType());
    assertEquals(
        Types.subtypeOf(Object[].class),
        Types.newArrayType(
            TypeToken.of(Types.subtypeOf(Object[].class)).getComponentType().getType()));
    assertEquals(
        int.class, TypeToken.of(Types.subtypeOf(int[].class)).getComponentType().getType());

    assertEquals(
        Types.subtypeOf(Object.class),
        TypeToken.of(Types.subtypeOf(Object[].class)).getComponentType().getType());
    assertEquals(
        Types.subtypeOf(Object[].class),
        Types.newArrayType(
            TypeToken.of(Types.subtypeOf(Object[].class)).getComponentType().getType()));
    assertEquals(
        int.class, TypeToken.of(Types.subtypeOf(int[].class)).getComponentType().getType());

    assertTrue(isComparable.apply(Integer.class));
    assertTrue(isComparable.apply(Float.class));
  }

  @J2ktIncompatible
  @GwtIncompatible // Predicates.subtypeOf
  public void testSubtypeOf_equality() {
    new EqualsTester()
        .addEqualityGroup(Predicates.subtypeOf(Integer.class))
        .addEqualityGroup(Predicates.subtypeOf(Number.class))

        return methodParametersFromSignature(methodInSubClass) == methodParametersFromSignature(method)
            // Subclass can override method return type
            && methodInSubClass.returnType.subtypeOf(method.returnType)
    }

    /**
     * Returns method parameters from method signature, e.g. "(Ljava/lang/String;I)V" -> "(Ljava/lang/String;I)"
     */

 * annotated by {@link TestSubtype}.
 *
 * <p>These declaration methods rely on Java static type checking to make sure what we want to
 * assert as subtypes are really subtypes according to javac. For example:
 *
 * {@snippet :
 * class MySubtypeTests extends SubtypeTester {
 *   @TestSubtype(suppressGetSubtype = true, suppressGetSupertype = true)

 * annotated by {@link TestSubtype}.
 *
 * <p>These declaration methods rely on Java static type checking to make sure what we want to
 * assert as subtypes are really subtypes according to javac. For example:
 *
 * {@snippet :
 * class MySubtypeTests extends SubtypeTester {
 *   @TestSubtype(suppressGetSubtype = true, suppressGetSupertype = true)