ProvisionException：無法提供，在玩框架

Question

我收到這些錯誤 ProvisionException: Unable to provision，請參閱以下錯誤：

com.google.inject.ProvisionException: Unable to provision, see the following errors:

1) Could not find a suitable constructor in models.factory.FactoryHandler. Classes must have either one (and only one) constructor annotated with @Inject or a zero-argument constructor that is not private.
  at models.factory.FactoryHandler.class(FactoryHandler.scala:7)
  while locating models.factory.FactoryHandler
    for parameter 0 at controllers.DirectUserController.<init>(DirectUserController.scala:90)
  while locating controllers.DirectUserController
    for parameter 7 at router.Routes.<init>(Routes.scala:124)
  while locating router.Routes
  while locating play.api.inject.RoutesProvider
  while locating play.api.routing.Router

1 error
     com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1025)
     com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1051)
     play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:321)
     play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:316)
     play.api.Application$class.routes(Application.scala:111)
     play.api.DefaultApplication.routes(Application.scala:240)
     play.api.Play$$anonfun$start$1.apply$mcV$sp(Play.scala:90)
     play.api.Play$$anonfun$start$1.apply(Play.scala:87)
     play.api.Play$$anonfun$start$1.apply(Play.scala:87)
     play.utils.Threads$.withContextClassLoader(Threads.scala:21)
     play.api.Play$.start(Play.scala:87)

這是代碼

class FactoryHandler(var s:String="real") {
  val log = LoggerFactory.getLogger(this.getClass)
  log.debug("choice {}",s)
}

這是 DirectUserController 的第 90 行

    class DirectUserController @Inject() (var factory:FactoryHandler) extends Controller {
//other Action code 
}

我還在路由文件中添加了代碼

routesGenerator := InjectedRoutesGenerator

我正在使用播放框架 2.4 請幫助我為什么我會收到此錯誤

Answer 1

您需要在 FactoryHandler 代碼中指定 @Inject() .. 閱讀錯誤，我認為它說明了它有什么問題。