Converting a Java collection into a Scala collection

Question

Related to Stack Overflow question Scala equivalent of new HashSet(Collection) , how do I convert a Java collection (java.util.List say) into a Scala c

Answer 1

Starting Scala 2.13, package scala.jdk.CollectionConverters replaces packages scala.collection.JavaConverters/JavaConversions._:

import scala.jdk.CollectionConverters._

// val javaList: java.util.List[String] = java.util.Arrays.asList("one","two","three")
javaList.asScala
// collection.mutable.Buffer[String] = Buffer("one", "two", "three")
javaList.asScala.toSet
// collection.immutable.Set[String] = Set("one", "two", "three")