tuple-operations.scala

val t = List((1, Set(
  Order(1, "2017-01-01", 100, "COMPLETE"), 
  Order(2, "2017-01-01", 20, "CLOSED"),
  Order(3, "2017-01-01", 301, "PENDING"),
  Order(4, "2017-01-01", 202, "CLOSED"),
  Order(5, "2017-01-01", 3013, "COMPLETE"),
  Order(6, "2017-01-01", 203, "PENDING"),
  Order(7, "2017-01-01", 3014, "COMPLETE"),
  Order(8, "2017-01-01", 20, "NEW"),
  Order(9, "2017-01-01", 301, "PENDING"),
  Order(10, "2017-01-01", 2, "CLOSED"),
  Order(11, "2017-01-01", 1, "COMPLETE"),
  Order(12, "2017-01-01", 3, "NEW"),
  Order(13, "2017-01-01", 301, "COMPLETE")
)),
(2, Set(
  Order(1, "2017-01-01", 100, "COMPLETE"), 
  Order(2, "2017-01-01", 20, "CLOSED"),
  Order(3, "2017-01-01", 301, "PENDING"),
  Order(4, "2017-01-01", 202, "CLOSED"),
  Order(5, "2017-01-01", 3013, "COMPLETE"),
  Order(6, "2017-01-01", 203, "PENDING"),
  Order(7, "2017-01-01", 3014, "COMPLETE"),
  Order(8, "2017-01-01", 20, "NEW"),
  Order(9, "2017-01-01", 301, "PENDING"),
  Order(10, "2017-01-01", 2, "CLOSED"),
  Order(11, "2017-01-01", 1, "COMPLETE"),
  Order(12, "2017-01-01", 3, "NEW"),
  Order(13, "2017-01-01", 301, "COMPLETE")
)))

// get min of orderId
t.map(a => (a._1, a._2.map(o => o.orderId).min))

// get order details with minimum orderId
t.map(a => (a._1, a._2.minBy(o => o.orderId)))

// get size of each set in the collection of key and value.
// Value is set in this case
t.map(a => (a._1, a._2.size))

// get completed orders from each of the set in the list of tuples
// Each tuple is nothing but key and value, where value is of type set
t.map(a => (a._1, a._2.filter(o => o.orderStatus == "COMPLETE"))).foreach(println)

// We can flatten the list by using flatMap
t.flatMap(rec => rec._2.filter(order => order.orderStatus == "COMPLETE")).foreach(println)