kotlin，如何从函数返回类类型

有一个基类a，B类和C类都从a扩展而来

in A it has function to create a retrofit service, which takes a class type as pram:

protected fun <T> createRemoteService(clazz: Class<T>, baseUrl: String): T {
    return Retrofit.Builder()
        .baseUrl(baseUrl)
        .client(okHttpClient)
        .addConverterFactory(GsonConverterFactory.create(createGson()))
        .build()
        .create(clazz)
}

and in class B and C, the service could be created as (with IBService::class.java or ICService::class.java passed in respectively):

in B:

var remoteServ: IBService
init {
    remoteApi = createRemoteService(IBService::class.java, getBaseUrl())
}

and in C:

var remoteServ: ICService
init {
    remoteApi = createRemoteService(ICService::class.java, getBaseUrl())
}

it is ok to pass IBService::class.java as the Class<T>

would like to have a abstract function in base A to return the class type

abstract fun<T> getRemoteServiceClassType() : Class<T>

so it could be done in base A to create the service by getting the class type

remoteServ: Any = createRemoteApi(getRemoteServiceClassType(), getBaseUrl())

并在B类中实现(获取错误):

override fun<T> getRemoteServiceClassType() : Class<T> {
    return IBService::class.java  //<=== got compiler error “Type inference 
                                  // failed. Expected type mismatch: required Class<T>
                                  // found Class<IBService>
}

interface IBService {
    @GET
    fun getRemoteData(@Url url: String,
                  @HeaderMap headers: Map<String, String>,
                  @QueryMap params: Map<String, String>?): 
        Call<BResponseData>

}

why cant return IBService::java.class for the Class<T>, but passing IBService::class.java to a function where requires a Class<T> is ok?