diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetFunctionType.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetFunctionType.java
index 3e64f25f47b..4f1a92948e7 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetFunctionType.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetFunctionType.java
@@ -28,7 +28,7 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
-public class JetFunctionType extends JetTypeElement {
+public class JetFunctionType extends JetElementImpl implements JetTypeElement {
 
     public static final JetToken RETURN_TYPE_SEPARATOR = JetTokens.ARROW;
 
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetNullableType.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetNullableType.java
index 250de87c3dc..13a4b4baac6 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetNullableType.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetNullableType.java
@@ -24,7 +24,7 @@ import org.jetbrains.jet.lexer.JetTokens;
 import java.util.Collections;
 import java.util.List;
 
-public class JetNullableType extends JetTypeElement {
+public class JetNullableType extends JetElementImpl implements JetTypeElement {
     public JetNullableType(@NotNull ASTNode node) {
         super(node);
     }
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetSelfType.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetSelfType.java
index a5ccd9f5ec0..05bf7660e48 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetSelfType.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetSelfType.java
@@ -22,7 +22,7 @@ import org.jetbrains.annotations.NotNull;
 import java.util.Collections;
 import java.util.List;
 
-public class JetSelfType extends JetTypeElement {
+public class JetSelfType extends JetElementImpl implements JetTypeElement {
     public JetSelfType(@NotNull ASTNode node) {
         super(node);
     }
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetTypeElement.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetTypeElement.java
index 39275cbc6af..b645f8da9d2 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetTypeElement.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetTypeElement.java
@@ -16,17 +16,11 @@
 
 package org.jetbrains.jet.lang.psi;
 
-import com.intellij.lang.ASTNode;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
-public abstract class JetTypeElement extends JetElementImpl {
-    public JetTypeElement(@NotNull ASTNode node) {
-        super(node);
-    }
-
+public interface JetTypeElement extends JetElement {
     @NotNull
-    public abstract List<JetTypeReference> getTypeArgumentsAsTypes();
-
+    List<JetTypeReference> getTypeArgumentsAsTypes();
 }
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetUserType.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetUserType.java
index dfdc991eecb..0991d75cf6b 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetUserType.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetUserType.java
@@ -26,7 +26,7 @@ import org.jetbrains.jet.lexer.JetTokens;
 import java.util.Collections;
 import java.util.List;
 
-public class JetUserType extends JetTypeElement {
+public class JetUserType extends JetElementImpl implements JetTypeElement {
     public JetUserType(@NotNull ASTNode node) {
         super(node);
     }