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这是我第一次使用Mongo Scala驱动程序（版本2.1），我注意到在处理我的一些case类时的奇怪行为 - 其中一些没有被识别因此classToCaseClassMap的结果是，其中一个解码数据沿着错误的路径行进，并以org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec中204行的错误java.util.NoSuchElementException: head of empty list结束，因为fieldClazzTypeArgs列表为空。Mongo Scala驱动程序2.1 - case class error
这里是顶部三分之一左右的堆栈跟踪的：
error: class java.util.NoSuchElementException: head of empty list
scala.collection.immutable.Nil$.head(List.scala:420)
scala.collection.immutable.Nil$.head(List.scala:417)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.readDocument(MacroCodec.scala:204)
palladium.calendar.dal.mongodb.Implicits$$anon$2$GoogleCalendarEventMacroCodec$3.readDocument(GoogleCalendarDAO.scala:55)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.readValue(MacroCodec.scala:173)
palladium.calendar.dal.mongodb.Implicits$$anon$2$GoogleCalendarEventMacroCodec$3.readValue(GoogleCalendarDAO.scala:55)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.decode(MacroCodec.scala:104)
palladium.calendar.dal.mongodb.Implicits$$anon$2$GoogleCalendarEventMacroCodec$3.decode(GoogleCalendarDAO.scala:55)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.readDocument(MacroCodec.scala:197)
palladium.calendar.dal.mongodb.Implicits$$anon$8$GoogleCalendarMacroCodec$3.readDocument(GoogleCalendarDAO.scala:61)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.readValue(MacroCodec.scala:173)
palladium.calendar.dal.mongodb.Implicits$$anon$8$GoogleCalendarMacroCodec$3.readValue(GoogleCalendarDAO.scala:61)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.readArray(MacroCodec.scala:187)
palladium.calendar.dal.mongodb.Implicits$$anon$8$GoogleCalendarMacroCodec$3.readArray(GoogleCalendarDAO.scala:61)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.readValue(MacroCodec.scala:174)
palladium.calendar.dal.mongodb.Implicits$$anon$8$GoogleCalendarMacroCodec$3.readValue(GoogleCalendarDAO.scala:61)
org.mongodb.scala.bson.codecs.macrocodecs.MacroCodec$class.decode(MacroCodec.scala:104)
palladium.calendar.dal.mongodb.Implicits$$anon$8$GoogleCalendarMacroCodec$3.decode(GoogleCalendarDAO.scala:61)
com.mongodb.operation.CommandResultArrayCodec.decode(CommandResultArrayCodec.java:52)
com.mongodb.operation.CommandResultDocumentCodec.readValue(CommandResultDocumentCodec.java:53)
org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:84)
org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:41)
org.bson.codecs.configuration.LazyCodec.decode(LazyCodec.java:47)
org.bson.codecs.BsonDocumentCodec.readValue(BsonDocumentCodec.java:101)
com.mongodb.operation.CommandResultDocumentCodec.readValue(CommandResultDocumentCodec.java:56)
org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:84)
org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:41)
com.mongodb.connection.ReplyMessage.<init>(ReplyMessage.java:57)
com.mongodb.connection.CommandProtocol.getResponseDocument(CommandProtocol.java:139)
com.mongodb.connection.CommandProtocol.access$000(CommandProtocol.java:51)
com.mongodb.connection.CommandProtocol$CommandResultCallback.callCallback(CommandProtocol.java:271)
com.mongodb.connection.ResponseCallback.onResult(ResponseCallback.java:48)
com.mongodb.connection.ResponseCallback.onResult(ResponseCallback.java:23)
com.mongodb.connection.DefaultConnectionPool$PooledConnection$2.onResult(DefaultConnectionPool.java:470)
com.mongodb.connection.DefaultConnectionPool$PooledConnection$2.onResult(DefaultConnectionPool.java:464)
com.mongodb.connection.UsageTrackingInternalConnection$3.onResult(UsageTrackingInternalConnection.java:119)
com.mongodb.connection.UsageTrackingInternalConnection$3.onResult(UsageTrackingInternalConnection.java:115)
com.mongodb.internal.async.ErrorHandlingResultCallback.onResult(ErrorHandlingResultCallback.java:49)
com.mongodb.connection.InternalStreamConnection.executeCallbackAndReceiveResponse(InternalStreamConnection.java:378)
com.mongodb.connection.InternalStreamConnection.access$1700(InternalStreamConnection.java:66)
com.mongodb.connection.InternalStreamConnection$ResponseBuffersCallback.onResult(InternalStreamConnection.java:420)
com.mongodb.connection.InternalStreamConnection$ResponseBuffersCallback.onResult(InternalStreamConnection.java:389)
com.mongodb.connection.InternalStreamConnection$ResponseHeaderCallback.onSuccess(InternalStreamConnection.java:562)
com.mongodb.connection.InternalStreamConnection$ResponseHeaderCallback.access$2200(InternalStreamConnection.java:517)
com.mongodb.connection.InternalStreamConnection$ResponseHeaderCallback$ResponseBodyCallback.onResult(InternalStreamConnection.java:584)
com.mongodb.connection.InternalStreamConnection$ResponseHeaderCallback$ResponseBodyCallback.onResult(InternalStreamConnection.java:568)
com.mongodb.connection.InternalStreamConnection$3.completed(InternalStreamConnection.java:447)
com.mongodb.connection.InternalStreamConnection$3.completed(InternalStreamConnection.java:444)
com.mongodb.connection.AsynchronousSocketChannelStream$BasicCompletionHandler.completed(AsynchronousSocketChannelStream.java:218)
com.mongodb.connection.AsynchronousSocketChannelStream$BasicCompletionHandler.completed(AsynchronousSocketChannelStream.java:201)
sun.nio.ch.Invoker.invokeUnchecked(Invoker.java:126)
sun.nio.ch.Invoker.invokeDirect(Invoker.java:157)
sun.nio.ch.UnixAsynchronousSocketChannelImpl.implRead(UnixAsynchronousSocketChannelImpl.java:553)
sun.nio.ch.AsynchronousSocketChannelImpl.read(AsynchronousSocketChannelImpl.java:276)
sun.nio.ch.AsynchronousSocketChannelImpl.read(AsynchronousSocketChannelImpl.java:297)
我的应用程序模型别人的谷歌日历。这里是我的情况下类：
case class GoogleDateTime(date: Option[DateTime] = None, dateTime: Option[DateTime])
case class LongId(id: Long)
case class GoogleCalendarEvent(id: String,
status: Option[String] = None,
htmlLink: Option[String] = None,
created: Option[DateTime] = None,
updated: Option[DateTime] = None,
creator: Option[GoogleWho] = None,
organizer: Option[GoogleWho] = None,
summary: Option[String],
description: Option[String] = None,
location: Option[String] = None,
start: GoogleDateTime,
end: GoogleDateTime,
extendedProperties: Option[GoogleEventExtendedProperties] = None)
case class GoogleCalendarEventList(nextPageToken: Option[String],
items: Option[List[GoogleCalendarEvent]])
case class GoogleWho(email: Option[String],
displayName: Option[String])
case class GoogleEventSharedProperties(createdBy: Option[String] = None,
sessionType: Option[String] = None,
sessionId: Option[LongId] = None,
locationId: Option[LongId] = None,
roomId: Option[LongId] = None)
case class GoogleEventExtendedProperties(shared: Option[GoogleEventSharedProperties])
Here is a link to a screenshot showing the contents of the classToCaseClassMap在发生错误的点。
的截图显示了六个项目，包括我的case类的四个地图：GoogleCalendarEvent，GoogleWho，GoogleDateTime和GoogleEventExtendedProperties。只有第一个（GoogleCalendarEvent）被正确识别为案例类。
我试图让有问题的类sealed但没有帮助。
这里是我创建CodecRegistry：
val dtMap = Map(BsonType.DATE_TIME -> classOf[DateTime])
val typeClassReplacedMap = new BsonTypeClassMap(JavaConversions.mapAsJavaMap(dtMap))
val gcCodecProvider = new DocumentCodecProvider(typeClassReplacedMap)
implicit val gcRegistry: CodecRegistry = fromRegistries(fromCodecs(dtCodec),
fromProviders(gcCodecProvider,
classOf[GoogleCalendarEvent],
classOf[GoogleDateTime],
classOf[LongId],
classOf[GoogleEventExtendedProperties],
classOf[GoogleEventSharedProperties],
classOf[GoogleWho],
classOf[GoogleCalendar]),
DEFAULT_CODEC_REGISTRY)
Here是示出数据访问码要旨，我如何使用它（在SBT控制台或IntelliJ IDEA的Scala的控制台）。
我正在重构的应用程序在Reactive Mongo版本0.11.7下工作正常，但我们需要将其迁移到正式支持的Mongo Scala驱动程序以使用新的Atlas数据库。在此时间之后
嗨“其中一些不被识别”，哪些不被识别。你可以在你使用mongoDB驱动程序的地方发布代码片段吗？对异常的堆栈跟踪也会有帮助。 – Teliatko
也许我在阅读我的文章后添加了这个内容（对不起，我一直在添加它）。该图像将显示包含六个项目的地图，包括我的四个案例类：GoogleCalendarEvent，GoogleWho，GoogleDateTime和GoogleEventExtendedProperties。只有第一个（GoogleCalendarEvent）被正确识别为案例类。 – KevinD
我添加了尽可能多的栈跟踪（前三名左右） – KevinD