2.8.0: scala hashmap keys to java array

Works for me in 2.8.0.final:

Welcome to Scala version 2.8.0.final (Java HotSpot(TM) 64-Bit Server
VM, Java 1.6.0_21).
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scala> import scala.collection.immutable._
import scala.collection.immutable._

scala> val map = HashMap(1->"a", 2->"b")
map: scala.collection.immutable.HashMap[Int,java.lang.String] =
Map((1,a), (2,b))

scala> map.keys.map(_.toString).toArray
res1: Array[java.lang.String] = Array(1, 2)

But you don't need to map if your keys are already Strings.

Regards,
Ruediger

2010/9/25 Josh Stratton :
> I'm having trouble finding an easy way to convert a hashmap's keys to
> a java String array.  Looking at the docs, I see a toArray() function,
> which my compiler doesn't see.  I'm running 2.8.0.  The documentation
> says "current", which is a little ambiguous as to what version it's
> for.
>
> http://www.scala-lang.org/api/current/scala/collection/Iterable.html
>
> I'd like to do something like this:
>
> // in java, Register.hashMap is a scala Object
> String[] keys = Register.hashMap.keys().toArray()
>
> I feel like I've seen a miriad of solutions online like JavaConversion
> libraries, but I can't tell if they're more for java to scala.  Also,
> I've seen some function like .asJava(), which would be extremely
> convenient, but that doesn't work.  Are the 2.8.0 docs posted
> anywhere?
>

On Sat, September 25, 2010 7:09 pm, Josh Stratton wrote:
> The documentation
> says "current", which is a little ambiguous as to what version it's
> for.

"current" always points to the documentation of the most recently released
stable version, in this case 2.8.0 final. If you check the title bar, it
actually says "Scala Standard Library (2.8.0)".

> Are the 2.8.0 docs posted anywhere?

The shortcuts to all the APIs are the following:

http://www.scala-lang.org/api -- most recent stable
http://www.scala-lang.org/api/current -- same as above
http://www.scala-lang.org/api/rc -- most recent rc
http://www.scala-lang.org/api/2.x.y -- docs for Scala version 2.x.y
http://www.scala-lang.org/api/nightly -- most recent nightly (library)
http://www.scala-lang.org/api/nightly-comp -- most recent nightly (compiler)

Toni