在Lift中定義一個MongoRecord，裏面有一個地圖

Question

我找不到定義MongoRecord的方法，在Lift-MongoRecord裏面有一個Map[String,String]字段。

的提升文檔說：

所有標準記錄字段的支持。還有對Mongo特定類型的支持; ObjectId，UUID，Pattern，List和Map。

如何定義Map和List字段？

Answer 1

我定義了一個BsonRecordMapField：

class BsonRecordMapField[OwnerType <: BsonRecord[OwnerType], SubRecordType <: BsonRecord[SubRecordType]] 
(rec: OwnerType, valueMeta: BsonMetaRecord[SubRecordType])(implicit mf: Manifest[SubRecordType]) 
    extends MongoMapField[OwnerType, SubRecordType](rec: OwnerType) { 

    import scala.collection.JavaConversions._ 

    override def asDBObject: DBObject = { 
    val javaMap = new HashMap[String, DBObject]() 
    for ((key, element) <- value) { 
     javaMap.put(key.asInstanceOf[String], element.asDBObject) 
    } 
    val dbl = new BasicDBObject(javaMap) 
    dbl 
    } 

    override def setFromDBObject(dbo: DBObject): Box[Map[String, SubRecordType]] = { 
    val mapResult: Map[String, SubRecordType] = (for ((key, dboEl) <- dbo.toMap.toSeq) yield (key.asInstanceOf[String], valueMeta.fromDBObject(dboEl.asInstanceOf[DBObject]))).toMap 
    setBox(Full(mapResult)) 
    } 


    override def asJValue = { 
    val fieldList = (for ((key, elem) <- value) yield JField(key, elem.asJValue)).toList 
    JObject(fieldList) 
    } 

    override def setFromJValue(jvalue: JValue) = jvalue match { 
    case JNothing | JNull if optional_? => setBox(Empty) 
    case JObject(fieldList) => val retrievedMap = fieldList.map { 
     field => 
     val key = field.name 
     val valRetrieved = valueMeta.fromJValue(field.value) openOr valueMeta.createRecord 
     (key, valRetrieved) 
    }.toMap 
    setBox(Full(retrievedMap)) 
    case other => setBox(FieldHelpers.expectedA("JObject", other)) 
    } 
} 

這是盜賊的隱式查詢：

class BsonRecordMapQueryField[M <: BsonRecord[M], B <: BsonRecord[B]](val field: BsonRecordMapField[M, B])(implicit mf: Manifest[B]) { 

    def at(key: String): BsonRecordField[M, B] = { 
    val listBox = field.setFromJValue(JObject(List(JField("notExisting", JInt(0))))) 
    val rec = listBox.open_!.head._2 
    new BsonRecordField[M, B](field.owner, rec.meta)(mf) { 
     override def name = field.name + "." + key 
    } 
    } 
} 

object ExtendedRogue extends Rogue { 
    implicit def bsonRecordMapFieldToBsonRecordMapQueryField[M <: BsonRecord[M], B <: BsonRecord[B]](f: BsonRecordMapField[M, B])(implicit mf: Manifest[B]): BsonRecordMapQueryField[M, B] = new BsonRecordMapQueryField[M, B](f) (mf) 


} 

您可以在地圖中現在使用的是在操作。

Answer 2

MongoMapField怎麼樣？