diff --git a/platform/lang-impl/src/com/intellij/codeInspection/ui/ExcludedInspectionTreeNodesManager.java b/platform/lang-impl/src/com/intellij/codeInspection/ui/ExcludedInspectionTreeNodesManager.java
index 62c3a96fea76..67a86b684c1d 100644
--- a/platform/lang-impl/src/com/intellij/codeInspection/ui/ExcludedInspectionTreeNodesManager.java
+++ b/platform/lang-impl/src/com/intellij/codeInspection/ui/ExcludedInspectionTreeNodesManager.java
@@ -23,7 +23,6 @@ import com.intellij.codeInspection.reference.RefEntity;
 import com.intellij.util.containers.FactoryMap;
 import gnu.trove.THashSet;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 import javax.swing.tree.TreeNode;
 import java.util.Map;
@@ -35,7 +34,6 @@ import java.util.Set;
 @SuppressWarnings("MismatchedQueryAndUpdateOfCollection")
 public class ExcludedInspectionTreeNodesManager {
   private final Map<Class, Set<Object>> myExcludedNodeObjects = new FactoryMap<Class, Set<Object>>() {
-    @Nullable
     @Override
     protected Set<Object> create(Class key) {
       return new THashSet<>();
@@ -43,7 +41,6 @@ public class ExcludedInspectionTreeNodesManager {
   };
 
   private final Map<String, Set<Object>> myExcludedByTool = new FactoryMap<String, Set<Object>>() {
-    @Nullable
     @Override
     protected Set<Object> create(String key) {
       return new THashSet<>();
diff --git a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionRootNodeImpl.java b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionRootNodeImpl.java
deleted file mode 100644
index ce5223208a79..000000000000
--- a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionRootNodeImpl.java
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * Copyright 2000-2016 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 com.intellij.codeInspection.ui;
-
-/**
- * @author Dmitry Batkovich
- */
-public class InspectionRootNodeImpl {
-}
diff --git a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTree.java b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTree.java
index a7e483f84940..a08fffb23132 100644
--- a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTree.java
+++ b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTree.java
@@ -352,7 +352,7 @@ public class InspectionTree extends Tree {
   }
 
   public void queueUpdate() {
-    ((InspectionRootNode) getRoot()).getUpdater().update(null, true);
+    ((InspectionRootNode) getRoot()).getUpdater().update(true);
   }
 
   public void restoreExpansionAndSelection(boolean treeNodesMightChange) {
diff --git a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeNode.java b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeNode.java
index 135d867b3a81..199557ca7af7 100644
--- a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeNode.java
+++ b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeNode.java
@@ -123,7 +123,7 @@ public abstract class InspectionTreeNode extends DefaultMutableTreeNode {
     super.add(newChild);
     if (myUpdater != null) {
       ((InspectionTreeNode)newChild).propagateUpdater(myUpdater);
-      myUpdater.updateWithPreviewPanel(this);
+      myUpdater.updateWithPreviewPanel();
     }
   }
 
@@ -132,7 +132,7 @@ public abstract class InspectionTreeNode extends DefaultMutableTreeNode {
     super.insert(newChild, childIndex);
     if (myUpdater != null) {
       ((InspectionTreeNode)newChild).propagateUpdater(myUpdater);
-      myUpdater.updateWithPreviewPanel(this);
+      myUpdater.updateWithPreviewPanel();
     }
   }
 
diff --git a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeUpdater.java b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeUpdater.java
index e6f099c90428..57fbde2e2722 100644
--- a/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeUpdater.java
+++ b/platform/lang-impl/src/com/intellij/codeInspection/ui/InspectionTreeUpdater.java
@@ -18,10 +18,8 @@ package com.intellij.codeInspection.ui;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.util.ui.update.MergingUpdateQueue;
 import com.intellij.util.ui.update.Update;
-import org.jetbrains.annotations.Nullable;
 
 import javax.swing.tree.DefaultTreeModel;
-import javax.swing.tree.TreeNode;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
@@ -37,12 +35,12 @@ public class InspectionTreeUpdater {
     myUpdateQueue = new MergingUpdateQueue("InspectionView", 100, true, view, view);
   }
 
-  public void updateWithPreviewPanel(@Nullable TreeNode node) {
+  public void updateWithPreviewPanel() {
     myDoUpdatePreviewPanel.set(true);
-    update(node, false);
+    update(false);
   }
 
-  public void update(@Nullable TreeNode node, boolean force) {
+  public void update(boolean force) {
     if (ApplicationManager.getApplication().isDispatchThread() && !force) {
       return;
     }
diff --git a/platform/lang-impl/src/com/intellij/codeInspection/ui/ProblemPreviewEditorPresentation.java b/platform/lang-impl/src/com/intellij/codeInspection/ui/ProblemPreviewEditorPresentation.java
index 9397b93905a9..243231ad1e99 100644
--- a/platform/lang-impl/src/com/intellij/codeInspection/ui/ProblemPreviewEditorPresentation.java
+++ b/platform/lang-impl/src/com/intellij/codeInspection/ui/ProblemPreviewEditorPresentation.java
@@ -19,7 +19,6 @@ import com.intellij.codeInspection.CommonProblemDescriptor;
 import com.intellij.codeInspection.ProblemDescriptorBase;
 import com.intellij.diff.tools.util.FoldingModelSupport;
 import com.intellij.diff.util.DiffDrawUtil;
-import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.FoldRegion;
 import com.intellij.openapi.editor.ScrollType;
 import com.intellij.openapi.editor.ex.DocumentEx;
@@ -39,7 +38,6 @@ import java.util.stream.Collectors;
  * @author Dmitry Batkovich
  */
 public class ProblemPreviewEditorPresentation {
-  private final static Logger LOG = Logger.getInstance(ProblemPreviewEditorPresentation.class);
   private final static int VIEW_ADDITIONAL_OFFSET = 4;
 
   private final EditorEx myEditor;