Collection filter by Xtend closure

CollectionFilter.xtend

import java.util.List
import static extension java.util.Collections.*

class CollectionFilter {
	def static void main(String[] _) {
		val values = newArrayList(1, 5, 0, -2, -10, 4)
		val filtered = positiveOnly(values)
		println(filtered)
	}

	def static positiveOnly(List<Integer> values) {
		values.filter(v| v > 0)
	}
}