Try examples 1

try_example1.scala

import scala.util.Try

val r = new java.util.Random
def randomBoolean = r.nextInt(8) != 0

def stringOrException = if (randomBoolean) "Hello" else throw new RuntimeException
def stringOrException2(string: String) = if(randomBoolean) s"$string world" else throw new ArithmeticException()
def stringOrException3(string: String) = if(randomBoolean) s"$string human" else throw new NullPointerException

val getString: String = Try(stringOrException).getOrElse("There was a problem getting the string") // Hello

val getStrings: Try[Try[String]] = Try(stringOrException).map(x => Try(stringOrException2(x))) //Success(Success(Hello world))

val getStrings2: Try[String] =
  Try(stringOrException).flatMap(x => Try(stringOrException2(x))).flatMap(x => Try(stringOrException3(x))) //Success(Hello world human)

// This is the same as above
for {
  s1 <- Try(stringOrException)
  s2 <- Try(stringOrException2(s1))
  s3 <- Try(stringOrException3(s2))
} yield s3


// def recover[U >: T](f: PartialFunction[Throwable, U]): Try[U]
getStrings2 recover {
  case r: RuntimeException => s"Exception has been thrown $r"
  case a: ArithmeticException => s"Exception has been thrown $a"
  case n: NullPointerException => s"Exception has been thrown $n"
}