Effiziente Weise Fall Objekt in scala passen

Question

Ich möchte Studenten und Mitarbeiter erhalten, die in Land Indien und China arbeitet

object Countries { 
    sealed trait Country {def name: String} 
    case object FRANCE extends Country {val name = "FRANCE"} 
    case object INDIA extends Country {val name = "INDIA"} 
    case object CHINA extends Country {val name = "CHINA"} 
    val list = Seq(FRANCE, INDIA, CHINA) 
} 

def getCountry: Option[Countries.Country] ={ 
    //some DB call to return country based on some parameters .I assume INDIA here 
    Option(Countries.INDIA) 
} 

case class Student(name: String, id: Symbol = Symbol("Id")) 

def getStudentName(name: Option[String]): Option[Student]={ 
    val std = name 
    .filterNot(_.isEmpty) 
    .map(Student(_)) 

    getCountry.collect { 
    case Countries.INDIA => std 
    case Countries.CHINA => std 
    }.flatten    
} 

case class Emp(id: Int) 

def getEmp(id: Option[String]): Option[Emp] = { 
    val emp = id.flatMap(_ => Option(Emp(id.get.toInt))) 
    getCountry.collect { 
    case Countries.INDIA => emp 
    case Countries.CHINA => emp 
    }.flatten 
} 

Gibt es eine effiziente Möglichkeit der wiederholten Code collect und Fall Matching Ich habe getan, zu vermeiden .

Answer 1

def ifCountry[T](result: => Option[T], countries: Country*) = getCountry 
    .filter(countries.toSet) 
    .flatMap(_ => result) 


def getStudentName(name: Option[String]) = ifCountry(
    name.filterNot(_.isEmpty).map(Student(_)), 
    INDIA, CHINA 
) 

def getEmp(id: Option[String]) = ifCountry(
    id.map(Emp(_)), 
    INDIA, CHINA 
}