Question

I have a Scala array of strings:

val names:Array[String] = something.map(...)

I need to call an Android(java) method that accepts a Collection

public void addAll (Collection<? extends T> collection)

How do I covert the Array to a Collection?

Answer 1

Java approach:

java.util.Arrays.asList(names: _*)

Scala approach:

import collection.JavaConversions._

val namesColl: java.util.Collection[String] = names.toSeq

In the latter approach names array is first converted to Seq[String] and then an implicit conversion located in JavaConversions figures out that Java collection is needed so it applies necessary transformation trasparently. Don’t worry, it is constant in time.