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 collection List
?
I am actually trying to convert a Java API call to Spring's SimpleJdbcTemplate
, which returns a java.util.List<T>
, into a Scala immutable HashSet
. So for example:
val l: java.util.List[String] = javaApi.query( ... )
val s: HashSet[String] = //make a set from l
This seems to work. Criticism is welcome!
import scala.collection.immutable.Set
import scala.collection.jcl.Buffer
val s: scala.collection.Set[String] =
Set(Buffer(javaApi.query( ... ) ) : _ *)
For future reference: With Scala 2.8, it could be done like this:
import scala.collection.JavaConversions._
val list = new java.util.ArrayList[String]()
list.add("test")
val set = list.toSet
set
is a scala.collection.immutable.Set[String]
after this.
Also see Ben James' answer for a more explicit way (using JavaConverters), which seems to be recommended now.