private[twitter] def isAssignableFrom()

in util-jackson/src/main/scala/com/twitter/util/jackson/caseclass/package.scala [38:98]
50 lines of code
5 McCabe index (conditional complexity)

  private[twitter] def isAssignableFrom(fromType: Class[_], toType: Class[_]): Boolean =
    Types.wrapperType(toType).isAssignableFrom(Types.wrapperType(fromType))

  /** Create a new [[CaseClassBeanProperty]]. Returns the [[CaseClassBeanProperty]] and the JacksonInject.Value */
  private[twitter] def newBeanProperty(
    context: DeserializationContext,
    javaType: JavaType,
    optionalJavaType: Option[JavaType],
    annotatedParameter: AnnotatedParameter,
    annotations: Iterable[Annotation],
    name: String,
    index: Int
  ): CaseClassBeanProperty = {
    // to support deserialization with JsonFormat and other Jackson annotations on fields,
    // the Jackson annotations must be carried in the mutator of the ValueInjector.
    val jacksonAnnotations = new AnnotationMap()
    val contextAnnotationsMap = new AnnotationMap()
    annotations.foreach { annotation =>
      if (annotation.annotationType().isAnnotationPresent(classOf[JacksonAnnotation])) {
        jacksonAnnotations.add(annotation)
      } else {
        contextAnnotationsMap.add(annotation)
      }
    }

    val mutator: AnnotatedMember = optionalJavaType match {
      case Some(optJavaType) =>
        newAnnotatedParameter(
          context,
          annotatedParameter,
          AnnotationMap.merge(jacksonAnnotations, contextAnnotationsMap),
          optJavaType,
          index)
      case _ =>
        newAnnotatedParameter(
          context,
          annotatedParameter,
          AnnotationMap.merge(jacksonAnnotations, contextAnnotationsMap),
          javaType,
          index)
    }

    val jacksonInjectValue = context.getAnnotationIntrospector.findInjectableValue(mutator)
    val beanProperty: BeanProperty = new ValueInjector(
      /* propName = */ new PropertyName(name),
      /* type =     */ optionalJavaType.getOrElse(javaType),
      /* mutator =  */ mutator,
      /* valueId =  */ if (jacksonInjectValue == null) null else jacksonInjectValue.getId
    ) {
      // ValueInjector no longer supports passing contextAnnotations as an
      // argument as of jackson 2.9.x
      // https://github.com/FasterXML/jackson-databind/commit/76381c528c9b75265e8b93bf6bb4532e4aa8e957#diff-dbcd29e987f27d95f964a674963a9066R24
      private[this] val contextAnnotations = contextAnnotationsMap

      override def getContextAnnotation[A <: Annotation](clazz: Class[A]): A = {
        contextAnnotations.get[A](clazz)
      }
    }

    CaseClassBeanProperty(valueObj = Option(jacksonInjectValue), property = beanProperty)
  }