Scala read file
621 ワード
// use loan pattern
// close resource after used
def using[A <: def="" close="" unit="" b="" a=""> B): B = {
try {
f(resource)
} finally {
resource.close()
}
}
// use Option as return
def readTextFile(filename: String): Option[List[String]] = {
try {
val lines = using(Source.fromFile(filename)) {
source =>
source.getLines.toList
}
Some(lines)
} catch {
case e: Exception => None
}
}
// print lines
val lines = readTextFile(filename).get
lines.foreach { line =>
println(line)
}