diff --git a/idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/JetChangeSignatureProcessor.kt b/idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/JetChangeSignatureProcessor.kt
index 7c7e00dcda9..8e14ed1da06 100644
--- a/idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/JetChangeSignatureProcessor.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/JetChangeSignatureProcessor.kt
@@ -30,10 +30,11 @@ import com.intellij.refactoring.rename.UnresolvableCollisionUsageInfo
 import com.intellij.usageView.UsageInfo
 import com.intellij.usageView.UsageViewDescriptor
 import com.intellij.util.containers.MultiMap
-import org.jetbrains.annotations.NotNull
 import org.jetbrains.kotlin.idea.refactoring.changeSignature.usages.JetUsageInfo
 import org.jetbrains.kotlin.idea.refactoring.changeSignature.usages.KotlinWrapperForJavaUsageInfos
-import java.util.*
+import java.util.ArrayList
+import java.util.Arrays
+import java.util.LinkedHashSet
 
 public class JetChangeSignatureProcessor(project: Project,
                                          changeInfo: JetChangeInfo,
@@ -103,7 +104,7 @@ public class JetChangeSignatureProcessor(project: Project,
         return true
     }
 
-    override fun isPreviewUsages(NotNull usages: Array<out UsageInfo>): Boolean = isPreviewUsages()
+    override fun isPreviewUsages(usages: Array<out UsageInfo>): Boolean = isPreviewUsages()
 
     override fun getCommandName() = commandName
 }