Scala and Spark for Big Data Analytics

Creating an Either

Either[X, Y] is an instance that contains either an instance of X or an instance of Y but not both. We call these subtypes left and right of Either. Creating an Either is trivial. But it's very powerful sometimes to use it in your program:

package com.chapter3.ScalaFPimport java.net.URLimport scala.io.Sourceobject Either {  def getData(dataURL: URL): Either[String, Source] =    if (dataURL.getHost.contains("xxx"))      Left("Requested URL is blocked or prohibited!")    else      Right(Source.fromURL(dataURL))        def main(args: Array[String]) {      val either1 = getData(new URL("http://www.xxx.com"))          println(either1)            val either2 = getData(new URL("http://www.google.com"))          println(either2)  }}

Now, if we pass any arbitrary URL that doesn't contain ...