diff --git a/platform/util-rt/src/com/intellij/openapi/util/io/FileUtilRt.java b/platform/util-rt/src/com/intellij/openapi/util/io/FileUtilRt.java
index db39aa8c2372..d869597e7c4a 100644
--- a/platform/util-rt/src/com/intellij/openapi/util/io/FileUtilRt.java
+++ b/platform/util-rt/src/com/intellij/openapi/util/io/FileUtilRt.java
@@ -6,10 +6,7 @@ import com.intellij.openapi.diagnostic.LoggerRt;
 import com.intellij.openapi.util.SystemInfoRt;
 import com.intellij.openapi.util.text.StringUtilRt;
 import com.intellij.util.ArrayUtilRt;
-import org.jetbrains.annotations.Contract;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-import org.jetbrains.annotations.TestOnly;
+import org.jetbrains.annotations.*;
 
 import java.io.*;
 import java.lang.reflect.InvocationHandler;
@@ -443,7 +440,7 @@ public class FileUtilRt {
     return fileName.subSequence(index + 1, fileName.length());
   }
 
-  public static boolean extensionEquals(@NotNull String filePath, @NotNull String extension) {
+  public static boolean extensionEquals(@NonNls @NotNull String filePath, @NonNls @NotNull String extension) {
     int extLen = extension.length();
     if (extLen == 0) {
       int lastSlash = Math.max(filePath.lastIndexOf('/'), filePath.lastIndexOf('\\'));