CSVReader (Scala)

	/**
	I wanted to find out how much lines of code a simple easy to use CSVReader would take in Scala.
	So here is a quick first try-out.
	**/
	package csv
	import java.lang.Boolean
	import scala.util.Try
	import scala.io.Source
	trait LineTokenizer {
	def tokenize(line: String, separator: String): Array[String] =
	line.split(separator).map(value => value.trim())
	def tokenize(line: String, separator: String, labels: List[String]): FieldSet =
	new FieldSet(labels, tokenize(line, separator))
	}
	trait LineMapper[T] {
	def mapLine(fieldSet: FieldSet): T
	}
	class CSVReader[T](file: String, separator: String, labels: List[String], hasHeader: Boolean,
	lineMapper: LineMapper[T]) extends LineTokenizer {
	val lines = Source.fromFile(file).getLines()
	val header = if (hasHeader) lines.next() else ""
	def hasNext: Boolean = lines.hasNext
	def next: T = lineMapper.mapLine(tokenize(lines.next(), separator, labels))
	}
	class FieldSet(labels: List[String], values: Array[String]) {
	val fields = labels.zip(values).toMap
	def readString(field: String): Option[String] = fields.get(field)
	def readBoolean(field: String): Option[Boolean] =
	convert(field, (s: String) => Boolean.valueOf(s))
	def readInt(field: String): Option[Int] = convert(field, (s: String) => s.toInt)
	def readLong(field: String): Option[Long] = convert(field, (s: String) => s.toLong)
	def readBigDecimal(field: String): Option[BigDecimal] =
	convert(field, (s: String) => BigDecimal.valueOf(s.toDouble))
	def convert[T](field: String, f: String => T): Option[T] = {
	readString(field) match {
	case None => None
	case Some(x) => Try[Option[T]](Some(f(x))).getOrElse(None)
	}
	}
	override def toString =
	List("FieldSet([", labels.mkString(","), "],[", values.mkString(","), "])").mkString
	}
	/***************** persons.csv ******************************************/
	name, age, male
	Robby, 36, true
	Valerie, 6, false
	Lindsey, 10, false
	/**************** USAGE *************************************************/
	import csv.{FieldSet, LineMapper, CSVReader}
	import java.lang.Boolean
	case class Person(name: String, age: Int, isMale: Boolean)
	val NAME = "NAME"
	val AGE = "AGE"
	val IS_MALE = "IS_MALE"
	val lineMapper = new LineMapper[Person] {
	override def mapLine(fieldSet: FieldSet): Person = {
	val name = fieldSet.readString(NAME).getOrElse("")
	val age = fieldSet.readInt(AGE).getOrElse(0)
	val isMale = fieldSet.readBoolean(IS_MALE).getOrElse(Boolean.FALSE)
	Person(name, age , isMale)
	}
	}
	val csvReader = new CSVReader[Person](
	"/Users/robbypelssers/Documents/persons.csv",
	",", List(NAME, AGE, IS_MALE),
	true,
	lineMapper
	)
	while (csvReader.hasNext) {
	println(csvReader.next)
	}

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