JavaCallingScalaHashMap.java

import scala.collection.immutable.HashMap$;
import scala.collection.immutable.HashMap;
import scala.collection.immutable.Map;
import scala.collection.mutable.Builder;
import scala.Tuple2;

public class JavaCallingScalaHashMap {
    public static void main( String[] args ) {
        Map<String, Integer> hashMap = HashMap$.MODULE$.empty();

        Builder<Tuple2<String, Integer>, HashMap<String, Integer>> b = HashMap$.MODULE$.newBuilder();
        b.addOne(new Tuple2<>("foo", 42));
        Map<String, Integer> hashMap2 = b.result();
    }
}