diff --git a/annotations/com/intellij/psi/impl/source/annotations.xml b/annotations/com/intellij/psi/impl/source/annotations.xml
new file mode 100644
index 00000000000..4b14ea4b748
--- /dev/null
+++ b/annotations/com/intellij/psi/impl/source/annotations.xml
@@ -0,0 +1,5 @@
+<root>
+  <item name='com.intellij.psi.impl.source.PsiFileImpl com.intellij.psi.impl.source.tree.FileElement calcTreeElement()'>
+    <annotation name='org.jetbrains.annotations.NotNull'/>
+  </item>
+</root>
\ No newline at end of file
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.java
deleted file mode 100644
index d4a90c35102..00000000000
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.java
+++ /dev/null
@@ -1,99 +0,0 @@
-/*
- * Copyright 2010-2013 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.jet.lang.psi;
-
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.*;
-import com.intellij.psi.impl.PsiManagerEx;
-import com.intellij.psi.impl.file.impl.FileManager;
-import com.intellij.psi.impl.source.tree.FileElement;
-import com.intellij.psi.search.GlobalSearchScope;
-import com.intellij.psi.tree.IElementType;
-import com.intellij.testFramework.LightVirtualFile;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.jet.plugin.JetFileType;
-
-public abstract class JetCodeFragment extends JetFile implements PsiCodeFragment {
-    private final Project project;
-
-    protected PsiElement context;
-    private GlobalSearchScope resolveScope;
-
-    public JetCodeFragment(Project project, String name, CharSequence text, IElementType elementType, PsiElement context) {
-        super(((PsiManagerEx) PsiManager.getInstance(project)).getFileManager().createFileViewProvider(
-                new LightVirtualFile(name, JetFileType.INSTANCE, text), true), false);
-        ((SingleRootFileViewProvider)getViewProvider()).forceCachedPsi(this);
-        init(TokenType.CODE_FRAGMENT, elementType);
-        this.project = project;
-        this.context = context;
-    }
-
-    @Override
-    public void forceResolveScope(GlobalSearchScope scope) {
-        resolveScope = scope;
-    }
-
-    @Override
-    public GlobalSearchScope getForcedResolveScope() {
-        return resolveScope;
-    }
-
-    @Override
-    public boolean isPhysical() {
-        return true;
-    }
-
-    @Override
-    public boolean isValid() {
-        return true;
-    }
-
-    @Override
-    public PsiElement getContext() {
-        return context;
-    }
-
-    @Override
-    @NotNull
-    public GlobalSearchScope getResolveScope() {
-        if (resolveScope != null) return resolveScope;
-        return super.getResolveScope();
-    }
-
-    @Override
-    protected JetCodeFragment clone() {
-        JetCodeFragment clone = (JetCodeFragment)cloneImpl((FileElement)calcTreeElement().clone());
-        clone.myOriginalFile = this;
-        FileManager fileManager = ((PsiManagerEx) PsiManager.getInstance(project)).getFileManager();
-        SingleRootFileViewProvider cloneViewProvider = (SingleRootFileViewProvider)fileManager.createFileViewProvider(new LightVirtualFile(
-                getName(),
-                JetFileType.INSTANCE,
-                getText()), true);
-        cloneViewProvider.forceCachedPsi(clone);
-        clone.myViewProvider = cloneViewProvider;
-        return clone;
-    }
-
-    private FileViewProvider myViewProvider = null;
-
-    @Override
-    @NotNull
-    public FileViewProvider getViewProvider() {
-        if (myViewProvider != null) return myViewProvider;
-        return super.getViewProvider();
-    }
-}
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.kt b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.kt
new file mode 100644
index 00000000000..bf845984f96
--- /dev/null
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetCodeFragment.kt
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2010-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.jet.lang.psi
+
+import com.intellij.openapi.project.Project
+import com.intellij.psi.*
+import com.intellij.psi.impl.PsiManagerEx
+import com.intellij.psi.impl.source.tree.FileElement
+import com.intellij.psi.search.GlobalSearchScope
+import com.intellij.psi.tree.IElementType
+import com.intellij.testFramework.LightVirtualFile
+import org.jetbrains.jet.plugin.JetFileType
+
+public abstract class JetCodeFragment(
+        val _project: Project,
+        name: String,
+        text: CharSequence,
+        elementType: IElementType,
+        val _context: PsiElement?
+): JetFile((PsiManager.getInstance(_project) as PsiManagerEx).getFileManager().createFileViewProvider(LightVirtualFile(name, JetFileType.INSTANCE, text), true), false), PsiCodeFragment {
+
+    {
+        (getViewProvider() as SingleRootFileViewProvider).forceCachedPsi(this)
+        init(TokenType.CODE_FRAGMENT, elementType)
+    }
+
+    private var _resolveScope: GlobalSearchScope? = null
+    private var _viewProvider: FileViewProvider? = null
+
+    override fun forceResolveScope(scope: GlobalSearchScope?) {
+        _resolveScope = scope
+    }
+
+    override fun getForcedResolveScope() = _resolveScope
+
+    override fun isPhysical() = true
+
+    override fun isValid() = true
+
+    override fun getContext() = _context
+
+    override fun getResolveScope() = _resolveScope ?: super<JetFile>.getResolveScope()
+
+    override fun clone(): JetCodeFragment {
+        val clone = cloneImpl(calcTreeElement().clone() as FileElement) as JetCodeFragment
+        clone.setOriginalFile(this)
+        val fileManager = (PsiManager.getInstance(_project) as PsiManagerEx).getFileManager()
+        val cloneViewProvider = fileManager.createFileViewProvider(LightVirtualFile(getName(), JetFileType.INSTANCE, getText()), true) as SingleRootFileViewProvider
+        cloneViewProvider.forceCachedPsi(clone)
+        clone._viewProvider = cloneViewProvider
+        return clone
+    }
+
+    override fun getViewProvider() = _viewProvider ?: super<JetFile>.getViewProvider()
+}