diff --git a/platform/editor-ui-api/src/com/intellij/ide/ui/UISettingsListener.java b/platform/editor-ui-api/src/com/intellij/ide/ui/UISettingsListener.java
index c73690696c4d..9e7183d09f90 100644
--- a/platform/editor-ui-api/src/com/intellij/ide/ui/UISettingsListener.java
+++ b/platform/editor-ui-api/src/com/intellij/ide/ui/UISettingsListener.java
@@ -29,6 +29,7 @@ import java.util.EventListener;
  * @see UISettings#fireUISettingsChanged()
  * @see com.intellij.util.ComponentTreeEventDispatcher
  */
+@FunctionalInterface
 public interface UISettingsListener extends EventListener {
 
   Topic<UISettingsListener> TOPIC = Topic.create("UI settings", UISettingsListener.class);
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorComposite.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorComposite.java
index ee70ae338e1f..2383125da214 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorComposite.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorComposite.java
@@ -84,7 +84,7 @@ public abstract class EditorComposite implements Disposable {
    * "close non modified editors first" feature.
    */
   private final long myInitialFileTimeStamp;
-  protected TabbedPaneWrapper myTabbedPaneWrapper;
+  TabbedPaneWrapper myTabbedPaneWrapper;
   private final MyComponent myComponent;
   private final FocusWatcher myFocusWatcher;
   /**
@@ -97,12 +97,12 @@ public abstract class EditorComposite implements Disposable {
   private final Map<FileEditor, String> myDisplayNames = ContainerUtil.newHashMap();
 
   /**
-   * @param file <code>file</code> for which composite is being constructed
+   * @param file {@code file} for which composite is being constructed
    *
-   * @param editors <code>edittors</code> that should be placed into the composite
+   * @param editors {@code edittors} that should be placed into the composite
    *
-   * @exception java.lang.IllegalArgumentException if <code>editors</code>
-   * is <code>null</code> or <code>providers</code> is <code>null</code> or <code>myEditor</code> arrays is empty
+   * @exception IllegalArgumentException if {@code editors}
+   * is {@code null} or {@code providers} is {@code null} or {@code myEditor} arrays is empty
    */
   EditorComposite(@NotNull final VirtualFile file,
                   @NotNull final FileEditor[] editors,
@@ -162,13 +162,8 @@ public abstract class EditorComposite implements Disposable {
   private TabbedPaneWrapper.AsJBTabs createTabbedPaneWrapper(FileEditor[] editors) {
     PrevNextActionsDescriptor descriptor = new PrevNextActionsDescriptor(IdeActions.ACTION_NEXT_EDITOR_TAB, IdeActions.ACTION_PREVIOUS_EDITOR_TAB);
     final TabbedPaneWrapper.AsJBTabs wrapper = new TabbedPaneWrapper.AsJBTabs(myFileEditorManager.getProject(), SwingConstants.BOTTOM, descriptor, this);
-    wrapper.getTabs().getPresentation().setPaintBorder(0, 0, 0, 0).setTabSidePaintBorder(1).setGhostsAlwaysVisible(true).setUiDecorator(new UiDecorator() {
-      @Override
-      @NotNull
-      public UiDecoration getDecoration() {
-        return new UiDecoration(null, new Insets(0, 8, 0, 8));
-      }
-    });
+    wrapper.getTabs().getPresentation().setPaintBorder(0, 0, 0, 0).setTabSidePaintBorder(1).setGhostsAlwaysVisible(true).setUiDecorator(
+      () -> new UiDecorator.UiDecoration(null, new Insets(0, 8, 0, 8)));
     wrapper.getTabs().getComponent().setBorder(new EmptyBorder(0, 0, 1, 0));
 
     boolean firstEditor = true;
@@ -277,7 +272,7 @@ public abstract class EditorComposite implements Disposable {
   }
 
   @NotNull
-  public List<JComponent> getTopComponents(@NotNull FileEditor editor) {
+  List<JComponent> getTopComponents(@NotNull FileEditor editor) {
     return getTopBottomComponents(editor, true);
   }
 
@@ -397,7 +392,7 @@ public abstract class EditorComposite implements Disposable {
   }
 
   /**
-   * @return <code>true</code> if the composite contains at least one
+   * @return {@code true} if the composite contains at least one
    * modified myEditor
    */
   public boolean isModified(){
@@ -441,7 +436,7 @@ public abstract class EditorComposite implements Disposable {
 
     @Override
     public boolean requestFocusInWindow() {
-      return myFocusComponent == null ? false : myFocusComponent.requestFocusInWindow();
+      return myFocusComponent != null && myFocusComponent.requestFocusInWindow();
     }
 
     @Override
@@ -453,7 +448,7 @@ public abstract class EditorComposite implements Disposable {
 
     @Override
     public boolean requestDefaultFocus() {
-      return myFocusComponent == null ? false : myFocusComponent.requestDefaultFocus();
+      return myFocusComponent != null && myFocusComponent.requestDefaultFocus();
     }
 
     @Override
@@ -472,9 +467,7 @@ public abstract class EditorComposite implements Disposable {
         if(component instanceof DataProvider && component != this){
           return ((DataProvider)component).getData(dataId);
         }
-        else{
-          return null;
-        }
+        return null;
       }
     }
   }
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorEmptyTextPainter.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorEmptyTextPainter.java
index 09af707f60cf..971d12aafcc2 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorEmptyTextPainter.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorEmptyTextPainter.java
@@ -32,7 +32,6 @@ import com.intellij.openapi.wm.ToolWindowManager;
 import com.intellij.openapi.wm.impl.IdeFrameImpl;
 import com.intellij.ui.Gray;
 import com.intellij.ui.JBColor;
-import com.intellij.util.PairFunction;
 import com.intellij.util.ui.JBUI;
 import com.intellij.util.ui.UIUtil;
 import org.jetbrains.annotations.NotNull;
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorHistoryManager.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorHistoryManager.java
index 5c3d51a970a7..555a4cdb520c 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorHistoryManager.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorHistoryManager.java
@@ -65,12 +65,7 @@ public final class EditorHistoryManager implements PersistentStateComponent<Elem
 
     MessageBusConnection connection = project.getMessageBus().connect();
 
-    connection.subscribe(UISettingsListener.TOPIC, new UISettingsListener() {
-      @Override
-      public void uiSettingsChanged(UISettings uiSettings) {
-        trimToSize();
-      }
-    });
+    connection.subscribe(UISettingsListener.TOPIC, uiSettings -> trimToSize());
 
     connection.subscribe(FileEditorManagerListener.Before.FILE_EDITOR_MANAGER, new FileEditorManagerListener.Before.Adapter() {
       @Override
@@ -247,11 +242,11 @@ public final class EditorHistoryManager implements PersistentStateComponent<Elem
   }
 
   /**
-   * Removes specified <code>file</code> from history. The method does
-   * nothing if <code>file</code> is not in the history.
+   * Removes specified {@code file} from history. The method does
+   * nothing if {@code file} is not in the history.
    *
-   * @exception IllegalArgumentException if <code>file</code>
-   * is <code>null</code>
+   * @exception IllegalArgumentException if {@code file}
+   * is {@code null}
    */
   public synchronized void removeFile(@NotNull final VirtualFile file){
     final HistoryEntry entry = getEntry(file);
@@ -268,7 +263,7 @@ public final class EditorHistoryManager implements PersistentStateComponent<Elem
   /**
    * @return may be null
    */
-  public FileEditorProvider getSelectedProvider(final VirtualFile file) {
+  FileEditorProvider getSelectedProvider(final VirtualFile file) {
     final HistoryEntry entry = getEntry(file);
     return entry != null ? entry.getSelectedProvider() : null;
   }
@@ -285,7 +280,7 @@ public final class EditorHistoryManager implements PersistentStateComponent<Elem
   }
 
   /**
-   * If total number of files in history more then <code>UISettings.RECENT_FILES_LIMIT</code>
+   * If total number of files in history more then {@code UISettings.RECENT_FILES_LIMIT}
    * then removes the oldest ones to fit the history to new size.
    */
   private synchronized void trimToSize(){
@@ -302,25 +297,19 @@ public final class EditorHistoryManager implements PersistentStateComponent<Elem
     // which is done via corresponding EditorProviders, those are not accessible before their
     // is initComponent() called
     final Element state = element.clone();
-    StartupManager.getInstance(myProject).runWhenProjectIsInitialized(new DumbAwareRunnable() {
-      @Override
-      public void run() {
-        for (Element e : state.getChildren(HistoryEntry.TAG)) {
-          try {
-            addEntry(HistoryEntry.createHeavy(myProject, e));
-          }
-          catch (InvalidDataException e1) {
-            // OK here
-          }
-          catch (ProcessCanceledException e1) {
-            // OK here
-          }
-          catch (Exception anyException) {
-            LOG.error(anyException);
-          }
+    StartupManager.getInstance(myProject).runWhenProjectIsInitialized((DumbAwareRunnable)() -> {
+      for (Element e : state.getChildren(HistoryEntry.TAG)) {
+        try {
+          addEntry(HistoryEntry.createHeavy(myProject, e));
+        }
+        catch (InvalidDataException | ProcessCanceledException e1) {
+          // OK here
+        }
+        catch (Exception anyException) {
+          LOG.error(anyException);
         }
-        trimToSize();
       }
+      trimToSize();
     });
   }
 
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorTabbedContainer.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorTabbedContainer.java
index 9641a07e5a5d..b42ba6fa0cce 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorTabbedContainer.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorTabbedContainer.java
@@ -85,9 +85,9 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
 
   @NonNls public static final String HELP_ID = "ideaInterface.editor";
 
-  private TabInfo.DragOutDelegate myDragOutDelegate = new MyDragOutDelegate();
+  private final TabInfo.DragOutDelegate myDragOutDelegate = new MyDragOutDelegate();
 
-  EditorTabbedContainer(final EditorWindow window, Project project, final int tabPlacement) {
+  EditorTabbedContainer(final EditorWindow window, Project project) {
     myWindow = window;
     myProject = project;
     final ActionManager actionManager = ActionManager.getInstance();
@@ -96,13 +96,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     myTabs.setTransferHandler(new MyTransferHandler());
     myTabs.setDataProvider(new MyDataProvider()).setPopupGroup(
       () -> (ActionGroup)CustomActionsSchema.getInstance().getCorrectedAction(IdeActions.GROUP_EDITOR_TAB_POPUP), ActionPlaces.EDITOR_TAB_POPUP, false).addTabMouseListener(new TabMouseListener()).getPresentation()
-      .setTabDraggingEnabled(true).setUiDecorator(new UiDecorator() {
-      @Override
-      @NotNull
-      public UiDecoration getDecoration() {
-        return new UiDecoration(null, new Insets(TabsUtil.TAB_VERTICAL_PADDING, 8, TabsUtil.TAB_VERTICAL_PADDING, 8));
-      }
-    }).setTabLabelActionsMouseDeadzone(TimedDeadzone.NULL).setGhostsAlwaysVisible(true).setTabLabelActionsAutoHide(false)
+      .setTabDraggingEnabled(true).setUiDecorator(() -> new UiDecorator.UiDecoration(null, new Insets(TabsUtil.TAB_VERTICAL_PADDING, 8, TabsUtil.TAB_VERTICAL_PADDING, 8))).setTabLabelActionsMouseDeadzone(TimedDeadzone.NULL).setGhostsAlwaysVisible(true).setTabLabelActionsAutoHide(false)
       .setActiveTabFillIn(EditorColorsManager.getInstance().getGlobalScheme().getDefaultBackground()).setPaintFocus(false).getJBTabs()
       .addListener(new TabsListener.Adapter() {
         @Override
@@ -124,17 +118,13 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
           }
         }
       })
-    .setSelectionChangeHandler(new JBTabs.SelectionChangeHandler() {
-      @NotNull
-      @Override
-      public ActionCallback execute(TabInfo info, boolean requestFocus, @NotNull final ActiveRunnable doChangeSelection) {
-        final ActionCallback result = new ActionCallback();
-        CommandProcessor.getInstance().executeCommand(myProject, () -> {
-          ((IdeDocumentHistoryImpl)IdeDocumentHistory.getInstance(myProject)).onSelectionChanged();
-          result.notify(doChangeSelection.run());
-        }, "EditorChange", null);
-        return result;
-      }
+    .setSelectionChangeHandler((info, requestFocus, doChangeSelection) -> {
+      final ActionCallback result = new ActionCallback();
+      CommandProcessor.getInstance().executeCommand(myProject, () -> {
+        ((IdeDocumentHistoryImpl)IdeDocumentHistory.getInstance(myProject)).onSelectionChanged();
+        result.notify(doChangeSelection.run());
+      }, "EditorChange", null);
+      return result;
     }).getPresentation().setRequestFocusOnLastFocusedComponent(true);
     myTabs.addMouseListener(new MouseAdapter() {
       @Override
@@ -163,12 +153,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
       }
     });
 
-    project.getMessageBus().connect().subscribe(UISettingsListener.TOPIC, new UISettingsListener() {
-      @Override
-      public void uiSettingsChanged(UISettings uiSettings) {
-        updateTabBorder();
-      }
-    });
+    project.getMessageBus().connect().subscribe(UISettingsListener.TOPIC, uiSettings -> updateTabBorder());
 
     Disposer.register(project, this);
   }
@@ -177,16 +162,18 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     return myTabs.getTabCount();
   }
 
+  @NotNull
   public ActionCallback setSelectedIndex(final int indexToSelect) {
     return setSelectedIndex(indexToSelect, true);
   }
 
+  @NotNull
   public ActionCallback setSelectedIndex(final int indexToSelect, boolean focusEditor) {
     if (indexToSelect >= myTabs.getTabCount()) return ActionCallback.REJECTED;
     return myTabs.select(myTabs.getTabAt(indexToSelect), focusEditor);
   }
 
-
+  @NotNull
   public static DockableEditor createDockableEditor(Project project, Image image, VirtualFile file, Presentation presentation, EditorWindow window) {
     return new DockableEditor(project, image, file, presentation, window.getSize(), window.isFilePinned(file));
   }
@@ -208,10 +195,10 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     List<String> leftIds = mgr.getIdsOn(ToolWindowAnchor.LEFT);
 
     if (!uiSettings.HIDE_TOOL_STRIPES && !uiSettings.PRESENTATION_MODE) {
-      border.top = topIds.size() > 0 ? 1 : 0;
-      border.bottom = bottom.size() > 0 ? 1 : 0;
-      border.left = leftIds.size() > 0 ? 1 : 0;
-      border.right = rightIds.size() > 0 ? 1 : 0;
+      border.top = !topIds.isEmpty() ? 1 : 0;
+      border.bottom = !bottom.isEmpty() ? 1 : 0;
+      border.left = !leftIds.isEmpty() ? 1 : 0;
+      border.right = !rightIds.isEmpty() ? 1 : 0;
     }
 
     for (String each : ids) {
@@ -262,17 +249,17 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     return myTabs.getIndexOf(myTabs.getSelectedInfo());
   }
 
-  public void setForegroundAt(final int index, final Color color) {
+  void setForegroundAt(final int index, final Color color) {
     myTabs.getTabAt(index).setDefaultForeground(color);
   }
 
-  public void setWaveColor(final int index, @Nullable final Color color) {
+  void setWaveColor(final int index, @Nullable final Color color) {
     final TabInfo tab = myTabs.getTabAt(index);
     tab.setDefaultStyle(color == null ? SimpleTextAttributes.STYLE_PLAIN : SimpleTextAttributes.STYLE_WAVED);
     tab.setDefaultWaveColor(color);
   }
 
-  public void setIconAt(final int index, final Icon icon) {
+  void setIconAt(final int index, final Icon icon) {
     myTabs.getTabAt(index).setIcon(icon);
   }
 
@@ -280,15 +267,15 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     myTabs.getTabAt(index).setText(text);
   }
 
-  public void setToolTipTextAt(final int index, final String text) {
+  void setToolTipTextAt(final int index, final String text) {
     myTabs.getTabAt(index).setTooltipText(text);
   }
 
-  public void setBackgroundColorAt(final int index, final Color color) {
+  void setBackgroundColorAt(final int index, final Color color) {
     myTabs.getTabAt(index).setTabColor(color);
   }
 
-  public void setTabLayoutPolicy(final int policy) {
+  void setTabLayoutPolicy(final int policy) {
     switch (policy) {
       case JTabbedPane.SCROLL_TAB_LAYOUT:
         myTabs.getPresentation().setSingleRow(true);
@@ -342,7 +329,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     myTabs.addTabSilently(tab, indexToInsert);
   }
 
-  public boolean isEmptyVisible() {
+  boolean isEmptyVisible() {
     return myTabs.isEmptyVisible();
   }
 
@@ -356,7 +343,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     }
   }
 
-  public void setPaintBlocked(boolean blocked) {
+  void setPaintBlocked(boolean blocked) {
     myTabs.setPaintBlocked(blocked, true);
   }
 
@@ -364,7 +351,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
 
     private final TabInfo myTab;
 
-    public MyQueryable(TabInfo tab) {
+    MyQueryable(TabInfo tab) {
       myTab = tab;
     }
 
@@ -421,7 +408,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
     ShadowAction myShadow;
     private final TabInfo myTabInfo;
 
-    public CloseTab(JComponent c, TabInfo info) {
+    CloseTab(JComponent c, TabInfo info) {
       myTabInfo = info;
       myShadow = new ShadowAction(this, ActionManager.getInstance().getAction(IdeActions.ACTION_CLOSE), c);
     }
@@ -555,7 +542,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
 
     @Override
     public void mouseClicked(MouseEvent e) {
-      if (UIUtil.isActionClick(e, MouseEvent.MOUSE_CLICKED) && (e.isMetaDown() || (!SystemInfo.isMac && e.isControlDown()))) {
+      if (UIUtil.isActionClick(e, MouseEvent.MOUSE_CLICKED) && (e.isMetaDown() || !SystemInfo.isMac && e.isControlDown())) {
         final TabInfo info = myTabs.findInfo(e);
         if (info != null && info.getObject() != null) {
           final VirtualFile vFile = (VirtualFile)info.getObject();
@@ -631,11 +618,11 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
 
   public static class DockableEditor implements DockableContent<VirtualFile> {
     final Image myImg;
-    private DockableEditorTabbedContainer myContainer;
-    private Presentation myPresentation;
-    private Dimension myPreferredSize;
-    private boolean myPinned;
-    private VirtualFile myFile;
+    private final DockableEditorTabbedContainer myContainer;
+    private final Presentation myPresentation;
+    private final Dimension myPreferredSize;
+    private final boolean myPinned;
+    private final VirtualFile myFile;
 
     public DockableEditor(Project project, Image img, VirtualFile file, Presentation presentation, Dimension preferredSize, boolean isFilePinned) {
       myImg = img;
@@ -707,7 +694,7 @@ public final class EditorTabbedContainer implements Disposable, CloseAction.Clos
   private static class MyShadowBorder implements Border {
     private final JBEditorTabs myTabs;
 
-    public MyShadowBorder(JBEditorTabs tabs) {
+    MyShadowBorder(JBEditorTabs tabs) {
       myTabs = tabs;
     }
 
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorWindow.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorWindow.java
index 1bfeddc08a3b..12e33ddab5ca 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorWindow.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorWindow.java
@@ -101,8 +101,8 @@ public class EditorWindow {
   } : AllIcons.General.Modified;
   private static final Icon GAP_ICON = EmptyIcon.create(MODIFIED_ICON);
 
-  private boolean myIsDisposed = false;
-  public static final Key<Integer> INITIAL_INDEX_KEY = Key.create("initial editor index");
+  private boolean myIsDisposed;
+  static final Key<Integer> INITIAL_INDEX_KEY = Key.create("initial editor index");
   private final Stack<Pair<String, Integer>> myRemovedTabs = new Stack<Pair<String, Integer>>() {
     @Override
     public void push(Pair<String, Integer> pair) {
@@ -112,7 +112,7 @@ public class EditorWindow {
       super.push(pair);
     }
   };
-  private AtomicBoolean myTabsHidingInProgress = new AtomicBoolean(false);
+  private final AtomicBoolean myTabsHidingInProgress = new AtomicBoolean(false);
   private final Stack<Pair<String, Integer>> myHiddenTabs = new Stack<>();
 
   protected EditorWindow(final EditorsSplitters owner) {
@@ -124,7 +124,7 @@ public class EditorWindow {
 
     final int tabPlacement = UISettings.getInstance().EDITOR_TAB_PLACEMENT;
     if (tabPlacement != UISettings.TABS_NONE && !UISettings.getInstance().PRESENTATION_MODE) {
-      createTabs(tabPlacement);
+      createTabs();
     }
 
     // Tab layout policy
@@ -140,9 +140,9 @@ public class EditorWindow {
     }
   }
 
-  private void createTabs(int tabPlacement) {
+  private void createTabs() {
     LOG.assertTrue (myTabbedPane == null);
-    myTabbedPane = new EditorTabbedContainer(this, getManager().getProject(), tabPlacement);
+    myTabbedPane = new EditorTabbedContainer(this, getManager().getProject());
     myPanel.add(myTabbedPane.getComponent(), BorderLayout.CENTER);
   }
 
@@ -190,11 +190,11 @@ public class EditorWindow {
     closeFile(file, disposeIfNeeded, true);
   }
 
-  public boolean hasClosedTabs() {
+  boolean hasClosedTabs() {
     return !myRemovedTabs.empty();
   }
 
-  public void restoreClosedTab() {
+  void restoreClosedTab() {
     assert hasClosedTabs() : "Nothing to restore";
 
     final Pair<String, Integer> info = myRemovedTabs.pop();
@@ -219,85 +219,82 @@ public class EditorWindow {
 
   public void closeFile(@NotNull final VirtualFile file, final boolean disposeIfNeeded, final boolean transferFocus) {
     final FileEditorManagerImpl editorManager = getManager();
-    editorManager.runChange(new FileEditorManagerChange() {
-      @Override
-      public void run(EditorsSplitters splitters) {
-        final List<EditorWithProviderComposite> editors = splitters.findEditorComposites(file);
-        if (editors.isEmpty()) return;
-        try {
-          final EditorWithProviderComposite editor = findFileComposite(file);
+    editorManager.runChange(splitters -> {
+      final List<EditorWithProviderComposite> editors = splitters.findEditorComposites(file);
+      if (editors.isEmpty()) return;
+      try {
+        final EditorWithProviderComposite editor = findFileComposite(file);
 
-          final FileEditorManagerListener.Before beforePublisher =
-            editorManager.getProject().getMessageBus().syncPublisher(FileEditorManagerListener.Before.FILE_EDITOR_MANAGER);
+        final FileEditorManagerListener.Before beforePublisher =
+          editorManager.getProject().getMessageBus().syncPublisher(FileEditorManagerListener.Before.FILE_EDITOR_MANAGER);
 
-          beforePublisher.beforeFileClosed(editorManager, file);
+        beforePublisher.beforeFileClosed(editorManager, file);
 
-          if (myTabbedPane != null && editor != null) {
-            final int componentIndex = findComponentIndex(editor.getComponent());
-            if (componentIndex >= 0) { // editor could close itself on decomposition
-              final int indexToSelect = calcIndexToSelect(file, componentIndex);
-              Pair<String, Integer> pair = Pair.create(file.getUrl(), componentIndex);
-              myRemovedTabs.push(pair);
-              if (myTabsHidingInProgress.get()) {
-                myHiddenTabs.push(pair);
-              }
-              myTabbedPane.removeTabAt(componentIndex, indexToSelect, transferFocus);
-              editorManager.disposeComposite(editor);
+        if (myTabbedPane != null && editor != null) {
+          final int componentIndex = findComponentIndex(editor.getComponent());
+          if (componentIndex >= 0) { // editor could close itself on decomposition
+            final int indexToSelect = calcIndexToSelect(file, componentIndex);
+            Pair<String, Integer> pair = Pair.create(file.getUrl(), componentIndex);
+            myRemovedTabs.push(pair);
+            if (myTabsHidingInProgress.get()) {
+              myHiddenTabs.push(pair);
             }
+            myTabbedPane.removeTabAt(componentIndex, indexToSelect, transferFocus);
+            editorManager.disposeComposite(editor);
           }
-          else {
+        }
+        else {
 
-            if (inSplitter()) {
-              Splitter splitter = (Splitter)myPanel.getParent();
-              JComponent otherComponent = splitter.getOtherComponent(myPanel);
+          if (inSplitter()) {
+            Splitter splitter = (Splitter)myPanel.getParent();
+            JComponent otherComponent = splitter.getOtherComponent(myPanel);
 
-              if (otherComponent != null) {
-                IdeFocusManager.findInstance().requestFocus(otherComponent, true);
-              }
-            }
-
-            myPanel.removeAll ();
-            if (editor != null) {
-              editorManager.disposeComposite(editor);
+            if (otherComponent != null) {
+              IdeFocusManager.findInstance().requestFocus(otherComponent, true);
             }
           }
 
-          if (disposeIfNeeded && getTabCount() == 0) {
-            removeFromSplitter();
-            if (UISettings.getInstance().EDITOR_TAB_PLACEMENT == UISettings.TABS_NONE) {
-              final EditorsSplitters owner = getOwner();
-              if (owner != null) {
-                final ThreeComponentsSplitter splitter = UIUtil.getParentOfType(ThreeComponentsSplitter.class, owner);
-                if (splitter != null) {
-                  splitter.revalidate();
-                  splitter.repaint();
-                }
-              }
-            }
+          myPanel.removeAll ();
+          if (editor != null) {
+            editorManager.disposeComposite(editor);
           }
-          else {
-            myPanel.revalidate();
-            if (myTabbedPane == null) {
-              // in tabless mode
-              myPanel.repaint();
+        }
+
+        if (disposeIfNeeded && getTabCount() == 0) {
+          removeFromSplitter();
+          if (UISettings.getInstance().EDITOR_TAB_PLACEMENT == UISettings.TABS_NONE) {
+            final EditorsSplitters owner = getOwner();
+            if (owner != null) {
+              final ThreeComponentsSplitter splitter = UIUtil.getParentOfType(ThreeComponentsSplitter.class, owner);
+              if (splitter != null) {
+                splitter.revalidate();
+                splitter.repaint();
+              }
             }
           }
         }
-        finally {
-          editorManager.removeSelectionRecord(file, EditorWindow.this);
-
-          editorManager.notifyPublisher(() -> {
-            final Project project = editorManager.getProject();
-            if (!project.isDisposed()) {
-              final FileEditorManagerListener afterPublisher =
-                project.getMessageBus().syncPublisher(FileEditorManagerListener.FILE_EDITOR_MANAGER);
-              afterPublisher.fileClosed(editorManager, file);
-            }
-          });
-
-          splitters.afterFileClosed(file);
+        else {
+          myPanel.revalidate();
+          if (myTabbedPane == null) {
+            // in tabless mode
+            myPanel.repaint();
+          }
         }
       }
+      finally {
+        editorManager.removeSelectionRecord(file, this);
+
+        editorManager.notifyPublisher(() -> {
+          final Project project = editorManager.getProject();
+          if (!project.isDisposed()) {
+            final FileEditorManagerListener afterPublisher =
+              project.getMessageBus().syncPublisher(FileEditorManagerListener.FILE_EDITOR_MANAGER);
+            afterPublisher.fileClosed(editorManager, file);
+          }
+        });
+
+        splitters.afterFileClosed(file);
+      }
     }, myOwner);
   }
 
@@ -360,7 +357,7 @@ public class EditorWindow {
         }
       }
     } else
-    if (uiSettings.ACTIVATE_RIGHT_EDITOR_ON_CLOSE && (fileIndex + 1 < myTabbedPane.getTabCount())) {
+    if (uiSettings.ACTIVATE_RIGHT_EDITOR_ON_CLOSE && fileIndex + 1 < myTabbedPane.getTabCount()) {
       return fileIndex + 1;
     }
 
@@ -381,13 +378,13 @@ public class EditorWindow {
     return myPanel.getComponentCount();
   }
 
-  public void setForegroundAt(final int index, final Color color) {
+  void setForegroundAt(final int index, final Color color) {
     if (myTabbedPane != null) {
       myTabbedPane.setForegroundAt(index, color);
     }
   }
 
-  public void setWaveColor(final int index, @Nullable final Color color) {
+  void setWaveColor(final int index, @Nullable final Color color) {
     if (myTabbedPane != null) {
       myTabbedPane.setWaveColor(index, color);
     }
@@ -418,18 +415,18 @@ public class EditorWindow {
   }
 
 
-  public void setTabLayoutPolicy(final int policy) {
+  void setTabLayoutPolicy(final int policy) {
     if (myTabbedPane != null) {
       myTabbedPane.setTabLayoutPolicy(policy);
     }
   }
 
-  public void setTabsPlacement(final int tabPlacement) {
+  void setTabsPlacement(final int tabPlacement) {
     if (tabPlacement != UISettings.TABS_NONE && !UISettings.getInstance().PRESENTATION_MODE) {
       if (myTabbedPane == null) {
         final EditorWithProviderComposite editor = getSelectedEditor();
         myPanel.removeAll();
-        createTabs(tabPlacement);
+        createTabs();
         restoreHiddenTabs();
         setEditor (editor, true);
       }
@@ -450,12 +447,8 @@ public class EditorWindow {
       for (VirtualFile file : files) {
         closeFile(file, false);
       }
-      getManager().runChange(new FileEditorManagerChange() {//Add flag switching activity to the end of queue
-        @Override
-        public void run(EditorsSplitters splitters) {
-          myTabsHidingInProgress.set(false);
-        }
-      }, myOwner);
+      //Add flag switching activity to the end of queue
+      getManager().runChange(splitters -> myTabsHidingInProgress.set(false), myOwner);
       disposeTabs();
       if (currentFile != null) {
         currentFile.putUserData(FileEditorManagerImpl.CLOSING_TO_REOPEN, null);
@@ -471,7 +464,7 @@ public class EditorWindow {
     myOwner.setCurrentWindow(this, requestFocus);
   }
 
-  public void updateFileBackgroundColor(@NotNull VirtualFile file) {
+  void updateFileBackgroundColor(@NotNull VirtualFile file) {
     final int index = findEditorIndex(findFileComposite(file));
     if (index != -1) {
       final Color color = EditorTabbedContainer.calcTabColor(getManager().getProject(), file);
@@ -483,7 +476,7 @@ public class EditorWindow {
     return myOwner;
   }
 
-  public boolean isEmptyVisible() {
+  boolean isEmptyVisible() {
     return myTabbedPane != null ? myTabbedPane.isEmptyVisible() : getFiles().length == 0;
   }
 
@@ -530,7 +523,7 @@ public class EditorWindow {
         @Override
         public void focusGained(FocusEvent e) {
           ApplicationManager.getApplication().invokeLater(() -> {
-            if (!TComp.this.hasFocus()) return;
+            if (!hasFocus()) return;
             final JComponent focus = myEditor.getSelectedEditorWithProvider().getFirst().getPreferredFocusedComponent();
             if (focus != null && !focus.hasFocus()) {
               IdeFocusManager.getGlobalInstance().requestFocus(focus, true);
@@ -552,7 +545,7 @@ public class EditorWindow {
         final VirtualFile virtualFile = myEditor.getFile();
         return virtualFile.isValid() ? virtualFile : null;
       }
-      else if (CommonDataKeys.PROJECT.is(dataId)) {
+      if (CommonDataKeys.PROJECT.is(dataId)) {
         return myEditor.getFileEditorManager().getProject();
       }
       return null;
@@ -840,7 +833,7 @@ public class EditorWindow {
     return res.toArray(new EditorWindow[res.size()]);
   }
 
-  public void changeOrientation() {
+  void changeOrientation() {
     checkConsistency();
     final Container parent = myPanel.getParent();
     if (parent instanceof Splitter) {
@@ -849,13 +842,13 @@ public class EditorWindow {
     }
   }
 
-  protected void updateFileIcon(VirtualFile file) {
+  void updateFileIcon(VirtualFile file) {
     final int index = findEditorIndex(findFileComposite(file));
     LOG.assertTrue(index != -1);
     setIconAt(index, getFileIcon(file));
   }
 
-  protected void updateFileName(VirtualFile file) {
+  void updateFileName(VirtualFile file) {
     final int index = findEditorIndex(findFileComposite(file));
     if (index != -1) {
       setTitleAt(index, EditorTabbedContainer.calcTabTitle(getManager().getProject(), file));
@@ -971,7 +964,7 @@ public class EditorWindow {
     }
   }
 
-  public void unsplitAll() {
+  void unsplitAll() {
     checkConsistency();
     while (inSplitter()) {
       unsplit(true);
@@ -1001,7 +994,7 @@ public class EditorWindow {
   }
 
 
-  public int findComponentIndex(final Component component) {
+  private int findComponentIndex(final Component component) {
     for (int i = 0; i != getTabCount(); ++i) {
       final EditorWithProviderComposite editor = getEditorAt(i);
       if (editor.getComponent ().equals (component)) {
@@ -1011,7 +1004,7 @@ public class EditorWindow {
     return -1;
   }
 
-  public int findEditorIndex(final EditorComposite editorToFind) {
+  int findEditorIndex(final EditorComposite editorToFind) {
     for (int i = 0; i != getTabCount(); ++i) {
       final EditorWithProviderComposite editor = getEditorAt(i);
       if (editor.equals (editorToFind)) {
@@ -1021,7 +1014,7 @@ public class EditorWindow {
     return -1;
   }
 
-  public int findFileIndex(final VirtualFile fileToFind) {
+  int findFileIndex(final VirtualFile fileToFind) {
     for (int i = 0; i != getTabCount(); ++i) {
       final VirtualFile file = getFileAt(i);
       if (file.equals (fileToFind)) {
@@ -1181,7 +1174,7 @@ public class EditorWindow {
     return isFileOpen (file) && !file.equals(fileToIgnore) && !isFilePinned(file);
   }
 
-  protected VirtualFile getFileAt(int i) {
+  VirtualFile getFileAt(int i) {
     return getEditorAt(i).getFile();
   }
 
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorsSplitters.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorsSplitters.java
index c76af1082e23..324a1f806d62 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorsSplitters.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/EditorsSplitters.java
@@ -25,7 +25,6 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
 import com.intellij.openapi.fileEditor.FileEditor;
-import com.intellij.openapi.keymap.Keymap;
 import com.intellij.openapi.keymap.KeymapManager;
 import com.intellij.openapi.keymap.KeymapManagerListener;
 import com.intellij.openapi.progress.ProgressIndicator;
@@ -99,12 +98,9 @@ public class EditorsSplitters extends IdePanePanel implements UISettingsListener
       Disposer.register(manager.getProject(), dockable);
       dockManager.register(dockable);
     }
-    KeymapManagerListener keymapListener = new KeymapManagerListener() {
-      @Override
-      public void activeKeymapChanged(Keymap keymap) {
-        invalidate();
-        repaint();
-      }
+    KeymapManagerListener keymapListener = keymap -> {
+      invalidate();
+      repaint();
     };
     KeymapManager.getInstance().addKeymapManagerListener(keymapListener, this);
   }
@@ -233,20 +229,17 @@ public class EditorsSplitters extends IdePanePanel implements UISettingsListener
     if (mySplittersElement != null) {
       initializeProgress();
       final JPanel comp = myUIBuilder.process(mySplittersElement, getTopPanel());
-      UIUtil.invokeAndWaitIfNeeded(new Runnable() {
-        @Override
-        public void run() {
-          if (comp != null) {
-            removeAll();
-            add(comp, BorderLayout.CENTER);
-            mySplittersElement = null;
-          }
-          // clear empty splitters
-          for (EditorWindow window : getWindows()) {
-            if (window.getEditors().length == 0) {
-              for (EditorWindow sibling : window.findSiblings()) {
-                sibling.unsplit(false);
-              }
+      UIUtil.invokeAndWaitIfNeeded((Runnable)() -> {
+        if (comp != null) {
+          removeAll();
+          add(comp, BorderLayout.CENTER);
+          mySplittersElement = null;
+        }
+        // clear empty splitters
+        for (EditorWindow window : getWindows()) {
+          if (window.getEditors().length == 0) {
+            for (EditorWindow sibling : window.findSiblings()) {
+              sibling.unsplit(false);
             }
           }
         }
@@ -337,12 +330,12 @@ public class EditorsSplitters extends IdePanePanel implements UISettingsListener
 
   @NotNull
   public FileEditor[] getSelectedEditors() {
-    List<FileEditor> editors = new ArrayList<>();
     Set<EditorWindow> windows = new THashSet<>(myWindows);
     final EditorWindow currentWindow = getCurrentWindow();
     if (currentWindow != null) {
       windows.add(currentWindow);
     }
+    List<FileEditor> editors = new ArrayList<>();
     for (final EditorWindow window : windows) {
       final EditorWithProviderComposite composite = window.getSelectedEditor();
       if (composite != null) {
@@ -818,12 +811,7 @@ public class EditorsSplitters extends IdePanePanel implements UISettingsListener
     @Override
     protected JPanel processFiles(@NotNull List<Element> fileElements, final JPanel context) {
       final Ref<EditorWindow> windowRef = new Ref<>();
-      UIUtil.invokeAndWaitIfNeeded(new Runnable() {
-        @Override
-        public void run() {
-          windowRef.set(context == null ? createEditorWindow() : findWindowWith(context));
-        }
-      });
+      UIUtil.invokeAndWaitIfNeeded((Runnable)() -> windowRef.set(context == null ? createEditorWindow() : findWindowWith(context)));
       final EditorWindow window = windowRef.get();
       LOG.assertTrue(window != null);
       VirtualFile focusedFile = null;
@@ -850,12 +838,8 @@ public class EditorsSplitters extends IdePanePanel implements UISettingsListener
           final HistoryEntry entry = HistoryEntry.createLight(fileEditorManager.getProject(), historyElement);
           final VirtualFile virtualFile = entry.getFile();
           if (virtualFile == null) throw new InvalidDataException("No file exists: " + entry.getFilePointer().getUrl());
-          Document document = ApplicationManager.getApplication().runReadAction(new Computable<Document>() {
-            @Override
-            public Document compute() {
-              return virtualFile.isValid() ? FileDocumentManager.getInstance().getDocument(virtualFile) : null;
-            }
-          });
+          Document document = ApplicationManager.getApplication().runReadAction(
+            (Computable<Document>)() -> virtualFile.isValid() ? FileDocumentManager.getInstance().getDocument(virtualFile) : null);
           final boolean isCurrentInTab = Boolean.valueOf(file.getAttributeValue(CURRENT_IN_TAB)).booleanValue();
           Boolean pin = Boolean.valueOf(file.getAttributeValue(PINNED));
           fileEditorManager.openFileImpl4(window, virtualFile, entry, isCurrentInTab, isCurrentInTab, pin, i);
@@ -890,34 +874,28 @@ public class EditorsSplitters extends IdePanePanel implements UISettingsListener
         final JPanel firstComponent = process(firstChild, null);
         final JPanel secondComponent = process(secondChild, null);
         final Ref<JPanel> panelRef = new Ref<>();
-        UIUtil.invokeAndWaitIfNeeded(new Runnable() {
-          @Override
-          public void run() {
-            JPanel panel = new JPanel(new BorderLayout());
-            panel.setOpaque(false);
-            Splitter splitter = new OnePixelSplitter(orientation, proportion, 0.1f, 0.9f);
-            panel.add(splitter, BorderLayout.CENTER);
-            splitter.setFirstComponent(firstComponent);
-            splitter.setSecondComponent(secondComponent);
-            panelRef.set(panel);
-          }
+        UIUtil.invokeAndWaitIfNeeded((Runnable)() -> {
+          JPanel panel = new JPanel(new BorderLayout());
+          panel.setOpaque(false);
+          Splitter splitter = new OnePixelSplitter(orientation, proportion, 0.1f, 0.9f);
+          panel.add(splitter, BorderLayout.CENTER);
+          splitter.setFirstComponent(firstComponent);
+          splitter.setSecondComponent(secondComponent);
+          panelRef.set(panel);
         });
         return panelRef.get();
       }
       final Ref<JPanel> firstComponent = new Ref<>();
       final Ref<JPanel> secondComponent = new Ref<>();
-      UIUtil.invokeAndWaitIfNeeded(new Runnable() {
-        @Override
-        public void run() {
-          if (context.getComponent(0) instanceof Splitter) {
-            Splitter splitter = (Splitter)context.getComponent(0);
-            firstComponent.set((JPanel)splitter.getFirstComponent());
-            secondComponent.set((JPanel)splitter.getSecondComponent());
-          }
-          else {
-            firstComponent.set(context);
-            secondComponent.set(context);
-          }
+      UIUtil.invokeAndWaitIfNeeded((Runnable)() -> {
+        if (context.getComponent(0) instanceof Splitter) {
+          Splitter splitter = (Splitter)context.getComponent(0);
+          firstComponent.set((JPanel)splitter.getFirstComponent());
+          secondComponent.set((JPanel)splitter.getSecondComponent());
+        }
+        else {
+          firstComponent.set(context);
+          secondComponent.set(context);
         }
       });
       process(firstChild, firstComponent.get());
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerChange.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerChange.java
index 6da7f1b65e0f..a811ac0fb975 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerChange.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerChange.java
@@ -15,6 +15,7 @@
  */
 package com.intellij.openapi.fileEditor.impl;
 
+@FunctionalInterface
 public interface FileEditorManagerChange {
 
   void run(EditorsSplitters splitters);
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerImpl.java
index d05c0446a3bc..aebe76296264 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorManagerImpl.java
@@ -134,12 +134,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   private DockableEditorContainerFactory myContentFactory;
   private static final AtomicInteger ourOpenFilesSetModificationCount = new AtomicInteger();
 
-  public static final ModificationTracker OPEN_FILE_SET_MODIFICATION_COUNT = new ModificationTracker() {
-    @Override
-    public long getModificationCount() {
-      return ourOpenFilesSetModificationCount.get();
-    }
-  };
+  static final ModificationTracker OPEN_FILE_SET_MODIFICATION_COUNT = ourOpenFilesSetModificationCount::get;
 
 
   public FileEditorManagerImpl(@NotNull Project project, DockManager dockManager) {
@@ -302,9 +297,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
     if (container instanceof DockableEditorTabbedContainer) {
       return ((DockableEditorTabbedContainer)container).getSplitters();
     }
-    else {
-      return getMainSplitters();
-    }
+    return getMainSplitters();
   }
 
   private final Object myInitLock = new Object();
@@ -365,7 +358,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   //-------------------------------------------------------
 
   /**
-   * @return color of the <code>file</code> which corresponds to the
+   * @return color of the {@code file} which corresponds to the
    *         file's status
    */
   public Color getFileColor(@NotNull final VirtualFile file) {
@@ -395,7 +388,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   }
 
   /**
-   * Updates tab color for the specified <code>file</code>. The <code>file</code>
+   * Updates tab color for the specified {@code file}. The {@code file}
    * should be opened in the myEditor, otherwise the method throws an assertion.
    */
   private void updateFileColor(@NotNull VirtualFile file) {
@@ -413,7 +406,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   }
 
   /**
-   * Updates tab icon for the specified <code>file</code>. The <code>file</code>
+   * Updates tab icon for the specified {@code file}. The {@code file}
    * should be opened in the myEditor, otherwise the method throws an assertion.
    */
   protected void updateFileIcon(@NotNull VirtualFile file) {
@@ -424,7 +417,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   }
 
   /**
-   * Updates tab title and tab tool tip for the specified <code>file</code>
+   * Updates tab title and tab tool tip for the specified {@code file}
    */
   void updateFileName(@Nullable final VirtualFile file) {
     // Queue here is to prevent title flickering when tab is being closed and two events arriving: with component==null and component==next focused tab
@@ -597,7 +590,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   @Override
   @NotNull
   public AsyncResult<EditorWindow> getActiveWindow() {
-    return getActiveSplittersAsync().subResult(splitters -> splitters.getCurrentWindow());
+    return getActiveSplittersAsync().subResult(EditorsSplitters::getCurrentWindow);
   }
 
   @Override
@@ -645,12 +638,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   private void closeFileImpl(@NotNull final VirtualFile file, final boolean moveFocus, boolean closeAllCopies) {
     assertDispatchThread();
     ourOpenFilesSetModificationCount.incrementAndGet();
-    runChange(new FileEditorManagerChange() {
-      @Override
-      public void run(EditorsSplitters splitters) {
-        splitters.closeFile(file, moveFocus);
-      }
-    }, closeAllCopies ? null : getActiveSplittersSync());
+    runChange(splitters -> splitters.closeFile(file, moveFocus), closeAllCopies ? null : getActiveSplittersSync());
   }
 
   //-------------------------------------- Open File ----------------------------------------
@@ -812,12 +800,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
 
     final Ref<EditorWithProviderComposite> compositeRef = new Ref<>();
 
-    UIUtil.invokeAndWaitIfNeeded(new Runnable() {
-      @Override
-      public void run() {
-        compositeRef.set(window.findFileComposite(file));
-      }
-    });
+    UIUtil.invokeAndWaitIfNeeded((Runnable)() -> compositeRef.set(window.findFileComposite(file)));
 
     final FileEditorProvider[] newProviders;
     final AsyncFileEditorProvider.Builder[] builders;
@@ -834,24 +817,18 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
         try {
           final FileEditorProvider provider = newProviders[i];
           LOG.assertTrue(provider != null, "Provider for file "+file+" is null. All providers: "+Arrays.asList(newProviders));
-          builders[i] = ApplicationManager.getApplication().runReadAction(new Computable<AsyncFileEditorProvider.Builder>() {
-            @Override
-            public AsyncFileEditorProvider.Builder compute() {
-              if (myProject.isDisposed() || !file.isValid()) {
-                return null;
-              }
-              LOG.assertTrue(provider.accept(myProject, file), "Provider " + provider + " doesn't accept file " + file);
-              return provider instanceof AsyncFileEditorProvider ? ((AsyncFileEditorProvider)provider).createEditorAsync(myProject, file) : null;
+          builders[i] = ApplicationManager.getApplication().runReadAction((Computable<AsyncFileEditorProvider.Builder>)() -> {
+            if (myProject.isDisposed() || !file.isValid()) {
+              return null;
             }
+            LOG.assertTrue(provider.accept(myProject, file), "Provider " + provider + " doesn't accept file " + file);
+            return provider instanceof AsyncFileEditorProvider ? ((AsyncFileEditorProvider)provider).createEditorAsync(myProject, file) : null;
           });
         }
         catch (ProcessCanceledException e) {
           throw e;
         }
-        catch (Exception e) {
-          LOG.error(e);
-        }
-        catch (AssertionError e) {
+        catch (Exception | AssertionError e) {
           LOG.error(e);
         }
       }
@@ -889,10 +866,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
           catch (ProcessCanceledException e) {
             throw e;
           }
-          catch (Exception e) {
-            LOG.error(e);
-          }
-          catch (AssertionError e) {
+          catch (Exception | AssertionError e) {
             LOG.error(e);
           }
         }
@@ -1398,7 +1372,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   @NotNull
   public List<JComponent> getTopComponents(@NotNull FileEditor editor) {
     final EditorComposite composite = getEditorComposite(editor);
-    return composite != null ? composite.getTopComponents(editor) : Collections.<JComponent>emptyList();
+    return composite != null ? composite.getTopComponents(editor) : Collections.emptyList();
   }
 
   @Override
@@ -1417,12 +1391,6 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
     }
   }
 
-  @NotNull
-  public List<JComponent> getBottomComponents(@NotNull FileEditor editor) {
-    final EditorComposite composite = getEditorComposite(editor);
-    return composite != null ? composite.getBottomComponents(editor) : Collections.<JComponent>emptyList();
-  }
-
   @Override
   public void addBottomComponent(@NotNull final FileEditor editor, @NotNull final JComponent component) {
     final EditorComposite composite = getEditorComposite(editor);
@@ -1481,28 +1449,25 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
      */
     connection.subscribe(UISettingsListener.TOPIC, new MyUISettingsListener());
 
-    StartupManager.getInstance(myProject).registerPostStartupActivity(new DumbAwareRunnable() {
-      @Override
-      public void run() {
-        if (myProject.isDisposed()) return;
-        setTabsMode(UISettings.getInstance().EDITOR_TAB_PLACEMENT != UISettings.TABS_NONE);
+    StartupManager.getInstance(myProject).registerPostStartupActivity((DumbAwareRunnable)() -> {
+      if (myProject.isDisposed()) return;
+      setTabsMode(UISettings.getInstance().EDITOR_TAB_PLACEMENT != UISettings.TABS_NONE);
 
-        ToolWindowManager.getInstance(myProject).invokeLater(() -> {
-          if (!myProject.isDisposed()) {
-            CommandProcessor.getInstance().executeCommand(myProject, () -> {
-              ApplicationManager.getApplication().invokeLater(() -> {
-                long currentTime = System.nanoTime();
-                Long startTime = myProject.getUserData(ProjectImpl.CREATION_TIME);
-                if (startTime != null) {
-                  LOG.info("Project opening took " + (currentTime - startTime.longValue()) / 1000000 + " ms");
-                  PluginManagerCore.dumpPluginClassStatistics();
-                }
-              }, myProject.getDisposed());
-              // group 1
-            }, "", null);
-          }
-        });
-      }
+      ToolWindowManager.getInstance(myProject).invokeLater(() -> {
+        if (!myProject.isDisposed()) {
+          CommandProcessor.getInstance().executeCommand(myProject, () -> {
+            ApplicationManager.getApplication().invokeLater(() -> {
+              long currentTime = System.nanoTime();
+              Long startTime = myProject.getUserData(ProjectImpl.CREATION_TIME);
+              if (startTime != null) {
+                LOG.info("Project opening took " + (currentTime - startTime.longValue()) / 1000000 + " ms");
+                PluginManagerCore.dumpPluginClassStatistics();
+              }
+            }, myProject.getDisposed());
+            // group 1
+          }, "", null);
+        }
+      });
     });
   }
 
@@ -1607,7 +1572,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
     return status != FileStatus.UNKNOWN && status != FileStatus.NOT_CHANGED;
   }
 
-  public void disposeComposite(@NotNull EditorWithProviderComposite editor) {
+  void disposeComposite(@NotNull EditorWithProviderComposite editor) {
     if (getAllEditors().length == 0) {
       setCurrentWindow(null);
     }
@@ -1637,7 +1602,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   }
 
   @Nullable
-  EditorComposite getLastSelected() {
+  private EditorComposite getLastSelected() {
     final EditorWindow currentWindow = getActiveSplittersSync().getCurrentWindow();
     if (currentWindow != null) {
       return currentWindow.getSelectedEditor();
@@ -1648,7 +1613,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
   /**
    * @param splitters - taken getAllSplitters() value if parameter is null
    */
-  public void runChange(@NotNull FileEditorManagerChange change, @Nullable EditorsSplitters splitters) {
+  void runChange(@NotNull FileEditorManagerChange change, @Nullable EditorsSplitters splitters) {
     Set<EditorsSplitters> target = new HashSet<>();
     if (splitters == null) {
       target.addAll(getAllSplitters());
@@ -1937,7 +1902,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
     return getOpenFiles();
   }
 
-  protected void queueUpdateFile(@NotNull final VirtualFile file) {
+  void queueUpdateFile(@NotNull final VirtualFile file) {
     myQueue.queue(new Update(file) {
       @Override
       public void run() {
@@ -1995,7 +1960,7 @@ public class FileEditorManagerImpl extends FileEditorManagerEx implements Persis
     mySelectionHistory.add(0, record);
   }
 
-  public void removeSelectionRecord(@NotNull VirtualFile file, @NotNull EditorWindow window) {
+  void removeSelectionRecord(@NotNull VirtualFile file, @NotNull EditorWindow window) {
     mySelectionHistory.remove(Pair.create(file, window));
     updateFileName(file);
   }
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorProviderManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorProviderManagerImpl.java
index 85c886d8104d..2293882bfc57 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorProviderManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileEditorProviderManagerImpl.java
@@ -31,10 +31,8 @@ import com.intellij.openapi.fileEditor.impl.text.TextEditorProvider;
 import com.intellij.openapi.project.DumbService;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Computable;
-import com.intellij.openapi.util.Condition;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.VirtualFile;
-import com.intellij.util.Function;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.xmlb.annotations.MapAnnotation;
 import org.jetbrains.annotations.NotNull;
@@ -85,14 +83,11 @@ public final class FileEditorProviderManagerImpl extends FileEditorProviderManag
     List<FileEditorProvider> sharedProviders = new ArrayList<>();
     boolean doNotShowTextEditor = false;
     for (final FileEditorProvider provider : myProviders) {
-      if (ApplicationManager.getApplication().runReadAction(new Computable<Boolean>() {
-        @Override
-        public Boolean compute() {
-          if (DumbService.isDumb(project) && !DumbService.isDumbAware(provider)) {
-            return false;
-          }
-          return provider.accept(project, file);
+      if (ApplicationManager.getApplication().runReadAction((Computable<Boolean>)() -> {
+        if (DumbService.isDumb(project) && !DumbService.isDumbAware(provider)) {
+          return false;
         }
+        return provider.accept(project, file);
       })) {
         sharedProviders.add(provider);
         doNotShowTextEditor |= provider.getPolicy() == FileEditorPolicy.HIDE_DEFAULT_EDITOR;
@@ -146,8 +141,6 @@ public final class FileEditorProviderManagerImpl extends FileEditorProviderManag
     mySelectedProviders.putAll(state.mySelectedProviders);
   }
 
-  private static final Function<FileEditorProvider, String> EDITOR_PROVIDER_STRING_FUNCTION = provider -> provider.getEditorTypeId();
-
   private final Map<String, String> mySelectedProviders = new HashMap<>();
 
   void providerSelected(EditorComposite composite) {
@@ -159,7 +152,7 @@ public final class FileEditorProviderManagerImpl extends FileEditorProviderManag
   }
 
   private static String computeKey(FileEditorProvider[] providers) {
-    return StringUtil.join(ContainerUtil.map(providers, EDITOR_PROVIDER_STRING_FUNCTION), ",");
+    return StringUtil.join(ContainerUtil.map(providers, FileEditorProvider::getEditorTypeId), ",");
   }
 
   @Nullable
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/HistoryEntry.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/HistoryEntry.java
index 9a590496ce1f..d9253e8d97bc 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/HistoryEntry.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/HistoryEntry.java
@@ -68,10 +68,10 @@ final class HistoryEntry {
   }
 
   @NotNull
-  public static HistoryEntry createLight(@NotNull VirtualFile file,
-                                         @NotNull FileEditorProvider[] providers,
-                                         @NotNull FileEditorState[] states,
-                                         @NotNull FileEditorProvider selectedProvider) {
+  static HistoryEntry createLight(@NotNull VirtualFile file,
+                                  @NotNull FileEditorProvider[] providers,
+                                  @NotNull FileEditorState[] states,
+                                  @NotNull FileEditorProvider selectedProvider) {
     VirtualFilePointer pointer = new LightFilePointer(file);
     HistoryEntry entry = new HistoryEntry(pointer, selectedProvider, null);
     for (int i = 0; i < providers.length; i++) {
@@ -81,7 +81,7 @@ final class HistoryEntry {
   }
 
   @NotNull
-  public static HistoryEntry createLight(@NotNull Project project, @NotNull Element e) throws InvalidDataException {
+  static HistoryEntry createLight(@NotNull Project project, @NotNull Element e) throws InvalidDataException {
     EntryData entryData = parseEntry(project, e);
 
     VirtualFilePointer pointer = new LightFilePointer(entryData.url);
@@ -93,11 +93,11 @@ final class HistoryEntry {
   }
 
   @NotNull
-  public static HistoryEntry createHeavy(@NotNull Project project,
-                                         @NotNull VirtualFile file,
-                                         @NotNull FileEditorProvider[] providers,
-                                         @NotNull FileEditorState[] states,
-                                         @NotNull FileEditorProvider selectedProvider) {
+  static HistoryEntry createHeavy(@NotNull Project project,
+                                  @NotNull VirtualFile file,
+                                  @NotNull FileEditorProvider[] providers,
+                                  @NotNull FileEditorState[] states,
+                                  @NotNull FileEditorProvider selectedProvider) {
     if (project.isDisposed()) return createLight(file, providers, states, selectedProvider);
 
     Disposable disposable = Disposer.newDisposable();
@@ -115,7 +115,7 @@ final class HistoryEntry {
   }
 
   @NotNull
-  public static HistoryEntry createHeavy(@NotNull Project project, @NotNull Element e) throws InvalidDataException {
+  static HistoryEntry createHeavy(@NotNull Project project, @NotNull Element e) throws InvalidDataException {
     if (project.isDisposed()) return createLight(project, e);
 
     EntryData entryData = parseEntry(project, e);
@@ -145,16 +145,16 @@ final class HistoryEntry {
     return myProvider2State.get(provider);
   }
 
-  public void putState(@NotNull FileEditorProvider provider, @NotNull FileEditorState state) {
+  void putState(@NotNull FileEditorProvider provider, @NotNull FileEditorState state) {
     myProvider2State.put(provider, state);
   }
 
   @Nullable
-  public FileEditorProvider getSelectedProvider() {
+  FileEditorProvider getSelectedProvider() {
     return mySelectedProvider;
   }
 
-  public void setSelectedProvider(@Nullable FileEditorProvider value) {
+  void setSelectedProvider(@Nullable FileEditorProvider value) {
     mySelectedProvider = value;
   }
 
@@ -163,7 +163,7 @@ final class HistoryEntry {
   }
 
   /**
-   * @return element that was added to the <code>element</code>.
+   * @return element that was added to the {@code element}.
    * Returned element has tag {@link #TAG}. Never null.
    */
   public Element writeExternal(Element element, Project project) {
@@ -226,13 +226,13 @@ final class HistoryEntry {
   }
 
   private static class EntryData {
-    @NotNull public final String url;
-    @NotNull public final List<Pair<FileEditorProvider, FileEditorState>> providerStates;
-    @Nullable public final FileEditorProvider selectedProvider;
+    @NotNull private final String url;
+    @NotNull private final List<Pair<FileEditorProvider, FileEditorState>> providerStates;
+    @Nullable private final FileEditorProvider selectedProvider;
 
-    public EntryData(@NotNull String url,
-                     @NotNull List<Pair<FileEditorProvider, FileEditorState>> providerStates,
-                     @Nullable FileEditorProvider selectedProvider) {
+    EntryData(@NotNull String url,
+              @NotNull List<Pair<FileEditorProvider, FileEditorState>> providerStates,
+              @Nullable FileEditorProvider selectedProvider) {
       this.url = url;
       this.providerStates = providerStates;
       this.selectedProvider = selectedProvider;
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/IdeDocumentHistoryImpl.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/IdeDocumentHistoryImpl.java
index c781024b7863..cbd702598845 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/IdeDocumentHistoryImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/IdeDocumentHistoryImpl.java
@@ -42,10 +42,7 @@ import org.jetbrains.annotations.TestOnly;
 import java.lang.ref.WeakReference;
 import java.util.*;
 
-@State(
-    name = "IdeDocumentHistory",
-    storages = {@Storage(StoragePathMacros.WORKSPACE_FILE)}
-)
+@State(name = "IdeDocumentHistory", storages = @Storage(StoragePathMacros.WORKSPACE_FILE))
 public class IdeDocumentHistoryImpl extends IdeDocumentHistory implements ProjectComponent, PersistentStateComponent<IdeDocumentHistoryImpl.RecentlyChangedFilesState> {
   private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.fileEditor.impl.IdeDocumentHistoryImpl");
 
@@ -63,21 +60,21 @@ public class IdeDocumentHistoryImpl extends IdeDocumentHistory implements Projec
 
   private final LinkedList<PlaceInfo> myBackPlaces = new LinkedList<>(); // LinkedList of PlaceInfo's
   private final LinkedList<PlaceInfo> myForwardPlaces = new LinkedList<>(); // LinkedList of PlaceInfo's
-  private boolean myBackInProgress = false;
-  private boolean myForwardInProgress = false;
-  private Object myLastGroupId = null;
+  private boolean myBackInProgress;
+  private boolean myForwardInProgress;
+  private Object myLastGroupId;
 
   // change's navigation
   private final LinkedList<PlaceInfo> myChangePlaces = new LinkedList<>(); // LinkedList of PlaceInfo's
-  private int myStartIndex = 0;
-  private int myCurrentIndex = 0;
-  private PlaceInfo myCurrentChangePlace = null;
+  private int myStartIndex;
+  private int myCurrentIndex;
+  private PlaceInfo myCurrentChangePlace;
 
-  private PlaceInfo myCommandStartPlace = null;
-  private boolean myCurrentCommandIsNavigation = false;
-  private boolean myCurrentCommandHasChanges = false;
+  private PlaceInfo myCommandStartPlace;
+  private boolean myCurrentCommandIsNavigation;
+  private boolean myCurrentCommandHasChanges;
   private final Set<VirtualFile> myChangedFilesInCurrentCommand = new THashSet<>();
-  private boolean myCurrentCommandHasMoves = false;
+  private boolean myCurrentCommandHasMoves;
 
   private final CommandListener myCommandListener = new CommandAdapter() {
     @Override
@@ -513,7 +510,10 @@ public class IdeDocumentHistoryImpl extends IdeDocumentHistory implements Projec
     private final String myEditorTypeId;
     private final WeakReference<EditorWindow> myWindow;
 
-    public PlaceInfo(@NotNull VirtualFile file, @NotNull FileEditorState navigationState, @NotNull String editorTypeId, @Nullable EditorWindow window) {
+    PlaceInfo(@NotNull VirtualFile file,
+              @NotNull FileEditorState navigationState,
+              @NotNull String editorTypeId,
+              @Nullable EditorWindow window) {
       myNavigationState = navigationState;
       myFile = file;
       myEditorTypeId = editorTypeId;
diff --git a/platform/util/src/com/intellij/openapi/util/NullUtils.java b/platform/util/src/com/intellij/openapi/util/NullUtils.java
index 7505305d41aa..222b0f7c4a0d 100644
--- a/platform/util/src/com/intellij/openapi/util/NullUtils.java
+++ b/platform/util/src/com/intellij/openapi/util/NullUtils.java
@@ -15,6 +15,8 @@
  */
 package com.intellij.openapi.util;
 
+import org.jetbrains.annotations.NotNull;
+
 /**
  * @author Konstantin Bulenkov
  */
@@ -26,11 +28,8 @@ public final class NullUtils {
    * @return <tt>true</tt> if all objects are not <tt>null</tt>,
    *         otherwise <tt>false</tt>
    */
-  public static boolean notNull(Object... objects) {
-    for (Object object : objects) {
-      if (object == null) return false;
-    }
-    return true;
+  public static boolean notNull(@NotNull Object... objects) {
+    return !hasNull(objects);
   }
 
   /**
@@ -40,7 +39,7 @@ public final class NullUtils {
    * @return <tt>false</tt> if all objects are not <tt>null</tt>,
    *         otherwise <tt>true</tt>
    */
-  public static boolean hasNull(Object... objects) {
+  public static boolean hasNull(@NotNull Object... objects) {
     for (Object object : objects) {
       if (object == null) return true;
     }
@@ -54,7 +53,7 @@ public final class NullUtils {
    * @return <tt>false</tt> if all objects are <tt>null</tt>,
    *         otherwise <tt>true</tt>
    */
-  public static boolean hasNotNull(Object... objects) {
+  public static boolean hasNotNull(@NotNull Object... objects) {
     for (Object object : objects) {
       if (object != null) return true;
     }