diff --git a/idea/src/org/jetbrains/jet/plugin/completion/LeafElementFilter.java b/idea/src/org/jetbrains/jet/plugin/completion/LeafElementFilter.java
index 6f4f089858e..d79123b44a1 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/LeafElementFilter.java
+++ b/idea/src/org/jetbrains/jet/plugin/completion/LeafElementFilter.java
@@ -25,7 +25,7 @@ import com.intellij.psi.tree.IElementType;
 public class LeafElementFilter implements ElementFilter {
     private static final ClassFilter LEAF_CLASS_FILTER = new ClassFilter(LeafPsiElement.class);
 
-    private IElementType myElementType;
+    private final IElementType myElementType;
 
     LeafElementFilter(IElementType elementType) {
         myElementType = elementType;