Reassign ArrayList in a better Way

Question

The below code is working, but its looking odd to me, is there any better way to this.

var res:scala.collection.mutable.LinkedHashMap[String,scala.collection.immutable.Map[String,String]]=??
var arList = new ArrayList[String]()
res.keySet.map(arList.add(_))
//here res key set changed so i want to reassign the list by new keySet
res=??                                                        //updated
arList.clear
res.keySet.map(arList.add(_))

its looking very odd that to call the .clear on arList

Why not using the `res.keySet`? Why do you need a `List` for that? — Nader Ghanbari, Nov 05 '14 at 05:15
@NaderHadjiGhanbari becuase `res.keSet` is `scala.collection.Set[String]` and i need `java.util.ArrayList[String]` , i Have to pass it for another method that needs `Array List` — Govind Singh, Nov 05 '14 at 05:17
@NaderHadjiGhanbari it will convert into `List` not `ArrayList` — Govind Singh, Nov 05 '14 at 06:04

score 5 · Accepted Answer · answered Nov 05 '14 at 05:30

You can use default JavaConverters.

  import scala.collection.JavaConverters._
  val list = new java.util.ArrayList(res.keySet.asJavaCollection)

I didn't get why do you need to do clear, is it some requirement that you pass ArrayList once and update it's content later?

Reassign ArrayList in a better Way

1 Answers1