diff --git a/idea/src/org/jetbrains/kotlin/idea/projectView/KotlinProjectViewUtil.kt b/idea/src/org/jetbrains/kotlin/idea/projectView/KotlinProjectViewUtil.kt
index 8a870295b7a..9e08b977baf 100644
--- a/idea/src/org/jetbrains/kotlin/idea/projectView/KotlinProjectViewUtil.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/projectView/KotlinProjectViewUtil.kt
@@ -14,71 +14,59 @@
  * limitations under the License.
  */
 
-package org.jetbrains.kotlin.idea.projectView;
+package org.jetbrains.kotlin.idea.projectView
 
-import com.intellij.ide.projectView.ViewSettings;
-import com.intellij.ide.util.treeView.AbstractTreeNode;
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.PsiElement;
-import com.intellij.psi.PsiFile;
-import org.jetbrains.kotlin.psi.KtClassOrObject;
-import org.jetbrains.kotlin.psi.KtDeclaration;
+import com.intellij.ide.projectView.ViewSettings
+import com.intellij.ide.util.treeView.AbstractTreeNode
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.psi.KtClassOrObject
+import java.util.*
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-
-public final class KotlinProjectViewUtil {
-
-    private KotlinProjectViewUtil() {
-    }
-
-    public static Collection<AbstractTreeNode> getClassOrObjectChildren(
-            KtClassOrObject classOrObject, Project project,
-                                                                        ViewSettings settings) {
-        if (classOrObject != null && settings.isShowMembers()) {
-            Collection<AbstractTreeNode> result = new ArrayList<AbstractTreeNode>();
-            List<KtDeclaration> declarations = classOrObject.getDeclarations();
-            for (KtDeclaration declaration : declarations) {
-                if (declaration instanceof KtClassOrObject) {
-                    result.add(new KtClassOrObjectTreeNode(project, (KtClassOrObject) declaration, settings));
-                }
-                else {
-                    result.add(new KtDeclarationTreeNode(project, declaration, settings));
-                }
+fun getClassOrObjectChildren(
+        classOrObject: KtClassOrObject?, project: Project?,
+        settings: ViewSettings): Collection<AbstractTreeNode<*>> {
+    if (classOrObject != null && settings.isShowMembers) {
+        val result = ArrayList<AbstractTreeNode<*>>()
+        val declarations = classOrObject.declarations
+        for (declaration in declarations) {
+            if (declaration is KtClassOrObject) {
+                result.add(KtClassOrObjectTreeNode(project, declaration, settings))
             }
-
-            return result;
-        }
-        else {
-            return Collections.emptyList();
-        }
-    }
-
-    public static boolean canRepresentPsiElement(PsiElement value, Object element, ViewSettings settings) {
-        if (value == null || !value.isValid()) {
-            return false;
-        }
-
-        PsiFile file = value.getContainingFile();
-        if (file != null && (file == element || file.getVirtualFile() == element)) {
-            return true;
-        }
-
-        if (value == element) {
-            return true;
-        }
-
-        if (!settings.isShowMembers()) {
-            if (element instanceof PsiElement && ((PsiElement) element).getContainingFile() != null) {
-                PsiFile elementFile = ((PsiElement) element).getContainingFile();
-                if (elementFile != null && file != null) {
-                    return elementFile.equals(file);
-                }
+            else {
+                result.add(KtDeclarationTreeNode(project, declaration, settings))
             }
         }
 
-        return false;
+        return result
+    }
+    else {
+        return emptyList()
     }
 }
+
+fun canRepresentPsiElement(value: PsiElement?, element: Any?, settings: ViewSettings): Boolean {
+    if (value == null || !value.isValid) {
+        return false
+    }
+
+    val file = value.containingFile
+    if (file != null && (file === element || file.virtualFile === element)) {
+        return true
+    }
+
+    if (value === element) {
+        return true
+    }
+
+    if (!settings.isShowMembers) {
+        if (element is PsiElement && element.containingFile != null) {
+            val elementFile = element.containingFile
+            if (elementFile != null && file != null) {
+                return elementFile == file
+            }
+        }
+    }
+
+    return false
+}
diff --git a/idea/src/org/jetbrains/kotlin/idea/projectView/KtClassOrObjectTreeNode.kt b/idea/src/org/jetbrains/kotlin/idea/projectView/KtClassOrObjectTreeNode.kt
index 48e2f92121a..3f2bbe1587e 100644
--- a/idea/src/org/jetbrains/kotlin/idea/projectView/KtClassOrObjectTreeNode.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/projectView/KtClassOrObjectTreeNode.kt
@@ -14,82 +14,69 @@
  * limitations under the License.
  */
 
-package org.jetbrains.kotlin.idea.projectView;
+package org.jetbrains.kotlin.idea.projectView
 
-import com.intellij.ide.projectView.PresentationData;
-import com.intellij.ide.projectView.ProjectView;
-import com.intellij.ide.projectView.ViewSettings;
-import com.intellij.ide.projectView.impl.nodes.AbstractPsiBasedNode;
-import com.intellij.ide.util.treeView.AbstractTreeNode;
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.PsiElement;
-import org.jetbrains.kotlin.idea.KotlinIconProvider;
-import org.jetbrains.kotlin.psi.KtClassOrObject;
-import org.jetbrains.kotlin.psi.KtPsiUtil;
+import com.intellij.ide.projectView.PresentationData
+import com.intellij.ide.projectView.ProjectView
+import com.intellij.ide.projectView.ViewSettings
+import com.intellij.ide.projectView.impl.nodes.AbstractPsiBasedNode
+import com.intellij.ide.util.treeView.AbstractTreeNode
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.idea.KotlinIconProvider
+import org.jetbrains.kotlin.psi.KtClassOrObject
+import org.jetbrains.kotlin.psi.KtPsiUtil
 
-import java.util.Collection;
+class KtClassOrObjectTreeNode(project: Project?, ktClassOrObject: KtClassOrObject, viewSettings: ViewSettings)
+    : AbstractPsiBasedNode<KtClassOrObject>(project, ktClassOrObject, viewSettings) {
 
-import static org.jetbrains.kotlin.idea.projectView.KotlinProjectViewUtil.canRepresentPsiElement;
-import static org.jetbrains.kotlin.idea.projectView.KotlinProjectViewUtil.getClassOrObjectChildren;
-
-public class KtClassOrObjectTreeNode extends AbstractPsiBasedNode<KtClassOrObject> {
-    protected KtClassOrObjectTreeNode(Project project, KtClassOrObject ktClassOrObject, ViewSettings viewSettings) {
-        super(project, ktClassOrObject, viewSettings);
+    override fun extractPsiFromValue(): PsiElement? {
+        return value
     }
 
-    @Override
-    protected PsiElement extractPsiFromValue() {
-        return getValue();
+    override fun getChildrenImpl(): Collection<AbstractTreeNode<*>>? {
+        return getClassOrObjectChildren(value, project, settings)
     }
 
-    @Override
-    protected Collection<AbstractTreeNode> getChildrenImpl() {
-        return getClassOrObjectChildren(getValue(), getProject(), getSettings());
-    }
-
-    private void update(AbstractTreeNode node) {
-        Project project = getProject();
+    private fun update(node: AbstractTreeNode<*>) {
+        val project = project
         if (project != null) {
-            ProjectView.getInstance(project).getCurrentProjectViewPane().getTreeBuilder().addSubtreeToUpdateByElement(node);
+            ProjectView.getInstance(project).currentProjectViewPane.treeBuilder.addSubtreeToUpdateByElement(node)
         }
     }
 
-    @Override
-    protected void updateImpl(PresentationData data) {
-        KtClassOrObject classOrObject = getValue();
+    override fun updateImpl(data: PresentationData) {
+        val classOrObject = value
         if (classOrObject != null) {
-            data.setPresentableText(classOrObject.getName());
+            data.setPresentableText(classOrObject.name)
 
-            AbstractTreeNode parent = getParent();
-            if (KotlinIconProvider.Companion.getMainClass(classOrObject.getContainingKtFile()) != null) {
-                if (parent instanceof KtFileTreeNode) {
-                    update(parent.getParent());
+            val parent = parent
+            if (KotlinIconProvider.getMainClass(classOrObject.getContainingKtFile()) != null) {
+                if (parent is KtFileTreeNode) {
+                    update(parent.getParent())
                 }
             }
             else {
-                if (!(parent instanceof KtClassOrObjectTreeNode) && !(parent instanceof KtFileTreeNode)) {
-                    update(parent);
+                if (parent !is KtClassOrObjectTreeNode && parent !is KtFileTreeNode) {
+                    update(parent)
                 }
             }
         }
     }
 
-    @Override
-    protected boolean isDeprecated() {
-        return KtPsiUtil.isDeprecated(getValue());
+    override fun isDeprecated(): Boolean {
+        return KtPsiUtil.isDeprecated(value)
     }
 
-    @Override
-    public boolean canRepresent(Object element) {
-        if (!isValid()) {
-            return false;
+    override fun canRepresent(element: Any?): Boolean {
+        if (!isValid) {
+            return false
         }
 
-        return super.canRepresent(element) || canRepresentPsiElement(getValue(), element, getSettings());
+        return super.canRepresent(element) || canRepresentPsiElement(value, element, settings)
     }
 
-    @Override
-    public int getWeight() {
-        return 20;
+    override fun getWeight(): Int {
+        return 20
     }
 }