diff --git a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSeqImpl.scala b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSeqImpl.scala
index 2d95f8e4..c9c697fb 100644
--- a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSeqImpl.scala
+++ b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSeqImpl.scala
@@ -2,7 +2,7 @@
 
 package stmbench7.scalastm
 
-import scala.collection.JavaConversions
+import scala.jdk.CollectionConverters.IteratorHasAsJava
 
 import stmbench7.backend.ImmutableCollection
 
@@ -10,7 +10,5 @@ class ImmutableSeqImpl[A](contents: Seq[A]) extends ImmutableCollection[A] {
   override def clone: ImmutableCollection[A] = this
   override def contains(element: A): Boolean = contents.contains(element)
   override def size: Int = contents.size
-
-  override def iterator: java.util.Iterator[A] =
-    JavaConversions.asJavaIterator(contents.iterator)
+  override def iterator: java.util.Iterator[A] = contents.iterator.asJava
 }
diff --git a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSetImpl.scala b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSetImpl.scala
index a350d560..9f607ff4 100644
--- a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSetImpl.scala
+++ b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ImmutableSetImpl.scala
@@ -2,7 +2,7 @@
 
 package stmbench7.scalastm
 
-import scala.collection.JavaConversions
+import scala.jdk.CollectionConverters.IteratorHasAsJava
 
 import scala.concurrent.stm.TSet
 
@@ -17,7 +17,5 @@ class ImmutableSetImpl[A](contents: TSet.View[A], shared: Boolean = true)
 
   override def contains(element: A): Boolean = contents.contains(element)
   override def size: Int = contents.size
-
-  override def iterator: java.util.Iterator[A] =
-    JavaConversions.asJavaIterator(contents.iterator)
+  override def iterator: java.util.Iterator[A] = contents.iterator.asJava
 }
diff --git a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/IndexImpl.scala b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/IndexImpl.scala
index 88fb9ee2..4324171c 100644
--- a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/IndexImpl.scala
+++ b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/IndexImpl.scala
@@ -2,8 +2,9 @@
 
 package stmbench7.scalastm
 
-import scala.collection.JavaConversions
 import scala.collection.immutable.TreeMap
+import scala.jdk.CollectionConverters.SetHasAsJava
+import scala.jdk.CollectionConverters.IteratorHasAsJava
 
 import scala.concurrent.stm.Ref
 
@@ -34,8 +35,7 @@ object IndexImpl {
 
     override def iterator: java.util.Iterator[V] = makeValuesIterator(underlying())
 
-    override def getKeys: java.lang.Iterable[K] =
-      JavaConversions.setAsJavaSet(underlying().keySet)
+    override def getKeys: java.lang.Iterable[K] = underlying().keySet.asJava
 
     override def getRange(minKey: K, maxKey: K): java.lang.Iterable[V] =
       new java.lang.Iterable[V] {
@@ -44,7 +44,7 @@ object IndexImpl {
       }
 
     private def makeValuesIterator(m: TreeMap[K, V]) = {
-      JavaConversions.asJavaIterator(m.values.iterator)
+      m.values.iterator.asJava
     }
   }
 }
diff --git a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/LargeSetImpl.scala b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/LargeSetImpl.scala
index 614c4265..f5147402 100644
--- a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/LargeSetImpl.scala
+++ b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/LargeSetImpl.scala
@@ -2,7 +2,7 @@
 
 package stmbench7.scalastm
 
-import scala.collection.JavaConversions
+import scala.jdk.CollectionConverters.IteratorHasAsJava
 
 import scala.concurrent.stm.TMap
 
@@ -15,7 +15,5 @@ class LargeSetImpl[A <: Comparable[A]] extends LargeSet[A] {
   override def remove(e: A): Boolean = underlying.remove(e).isDefined
   override def contains(e: A): Boolean = underlying.contains(e)
   override def size: Int = underlying.size
-
-  override def iterator: java.util.Iterator[A] =
-    JavaConversions.asJavaIterator(underlying.keysIterator)
+  override def iterator: java.util.Iterator[A] = underlying.keysIterator.asJava
 }
diff --git a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ScalaSTMInitializer.scala b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ScalaSTMInitializer.scala
index 16aad7d8..7691de76 100644
--- a/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ScalaSTMInitializer.scala
+++ b/benchmarks/scala-stm/src/main/scala/stmbench7/scalastm/ScalaSTMInitializer.scala
@@ -2,6 +2,8 @@
 
 package stmbench7.scalastm
 
+import scala.annotation.unused
+
 import scala.concurrent.stm.atomic
 import scala.concurrent.stm.Ref
 
@@ -23,6 +25,7 @@ import stmbench7.core.Module
 import stmbench7.core.Operation
 import stmbench7.impl.core.ConnectionImpl
 
+@unused("Referenced via string name")
 class ScalaSTMInitializer extends SynchMethodInitializer {
 
   def createOperationExecutorFactory(): OperationExecutorFactory =