diff --git a/jps/jps-common/src/org/jetbrains/kotlin/config/KotlinCommonJpsModelSerializerExtension.kt b/jps/jps-common/src/org/jetbrains/kotlin/config/KotlinCommonJpsModelSerializerExtension.kt
index a088979f6be..8dba547a291 100644
--- a/jps/jps-common/src/org/jetbrains/kotlin/config/KotlinCommonJpsModelSerializerExtension.kt
+++ b/jps/jps-common/src/org/jetbrains/kotlin/config/KotlinCommonJpsModelSerializerExtension.kt
@@ -1,26 +1,17 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
+package org.jetbrains.kotlin.config
 
-package org.jetbrains.kotlin.config;
+import org.jetbrains.jps.model.serialization.JpsModelSerializerExtension
+import org.jetbrains.jps.model.serialization.module.JpsModuleSourceRootPropertiesSerializer
 
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.jps.model.serialization.JpsModelSerializerExtension;
-import org.jetbrains.jps.model.serialization.module.JpsModuleSourceRootPropertiesSerializer;
-
-import java.util.Arrays;
-import java.util.List;
-
-public class KotlinCommonJpsModelSerializerExtension extends JpsModelSerializerExtension {
-    @NotNull
-    @Override
-    public List<? extends JpsModuleSourceRootPropertiesSerializer<?>> getModuleSourceRootPropertiesSerializers() {
-        return Arrays.asList(
-                KotlinSourceRootPropertiesSerializer.Source.INSTANCE,
-                KotlinSourceRootPropertiesSerializer.TestSource.INSTANCE,
-                KotlinResourceRootPropertiesSerializer.Resource.INSTANCE,
-                KotlinResourceRootPropertiesSerializer.TestResource.INSTANCE
-        );
-    }
+open class KotlinCommonJpsModelSerializerExtension : JpsModelSerializerExtension() {
+    override fun getModuleSourceRootPropertiesSerializers(): List<JpsModuleSourceRootPropertiesSerializer<*>> = listOf(
+        KotlinSourceRootPropertiesSerializer.Source,
+        KotlinSourceRootPropertiesSerializer.TestSource,
+        KotlinResourceRootPropertiesSerializer.Resource,
+        KotlinResourceRootPropertiesSerializer.TestResource
+    )
 }
\ No newline at end of file