diff --git a/java/java-psi-api/src/com/intellij/psi/compiled/ClassFileDecompilers.java b/java/java-psi-api/src/com/intellij/psi/compiled/ClassFileDecompilers.java
index 4bd2973a486d..e277eb3c3409 100644
--- a/java/java-psi-api/src/com/intellij/psi/compiled/ClassFileDecompilers.java
+++ b/java/java-psi-api/src/com/intellij/psi/compiled/ClassFileDecompilers.java
@@ -80,7 +80,7 @@ public final class ClassFileDecompilers {
     return ApplicationManager.getApplication().getService(ClassFileDecompilers.class);
   }
 
-  public final ExtensionPointName<Decompiler> EP_NAME = ExtensionPointName.create("com.intellij.psi.classFileDecompiler");
+  public final ExtensionPointName<Decompiler> EP_NAME = new ExtensionPointName<>("com.intellij.psi.classFileDecompiler");
 
   private ClassFileDecompilers() {
     EP_NAME.addChangeListener(() -> BinaryFileTypeDecompilers.getInstance().notifyDecompilersChange(), null);
diff --git a/platform/analysis-api/src/com/intellij/openapi/vfs/newvfs/RefreshQueue.java b/platform/analysis-api/src/com/intellij/openapi/vfs/newvfs/RefreshQueue.java
index 4eba8b80ce7f..f0fdfcfb14b8 100644
--- a/platform/analysis-api/src/com/intellij/openapi/vfs/newvfs/RefreshQueue.java
+++ b/platform/analysis-api/src/com/intellij/openapi/vfs/newvfs/RefreshQueue.java
@@ -5,6 +5,7 @@ import com.intellij.openapi.application.ModalityState;
 import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.vfs.newvfs.events.VFileEvent;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -51,7 +52,8 @@ public abstract class RefreshQueue {
     session.launch();
   }
 
+  @ApiStatus.Internal
   public abstract void processSingleEvent(@NotNull VFileEvent event);
 
   public abstract void cancelSession(long id);
-}
+}
\ No newline at end of file
diff --git a/platform/core-api/src/com/intellij/openapi/fileEditor/FileDocumentManager.java b/platform/core-api/src/com/intellij/openapi/fileEditor/FileDocumentManager.java
index b6d4ac087c7e..0c6203145732 100644
--- a/platform/core-api/src/com/intellij/openapi/fileEditor/FileDocumentManager.java
+++ b/platform/core-api/src/com/intellij/openapi/fileEditor/FileDocumentManager.java
@@ -27,8 +27,9 @@ public abstract class FileDocumentManager implements SavingRequestor {
   /**
    * Returns the document for the specified virtual file.<p/>
    *
-   * Documents are cached on weak or strong references, depending on the nature of the virtual file. If the document for the given virtual file is not yet cached,
-   * the file's contents are read from VFS and loaded into heap memory. An appropriate encoding is used. All line separators are converted to {@code \n}.<p/>
+   * Documents are cached on weak or strong references, depending on the nature of the virtual file. If the document
+   * for the given virtual file is not yet cached, the file's contents are read from VFS and loaded into heap memory.
+   * An appropriate encoding is used. All line separators are converted to {@code \n}.<p/>
    *
    * Should be invoked in a read action.
    *
@@ -169,7 +170,7 @@ public abstract class FileDocumentManager implements SavingRequestor {
     public static final WriteAccessStatus WRITABLE = new WriteAccessStatus(true);
 
     private final boolean myWithWriteAccess;
-    @NotNull private final String myReadOnlyMessage;
+    private final @NotNull String myReadOnlyMessage;
 
     private WriteAccessStatus(boolean withWriteAccess) {
       myWithWriteAccess = withWriteAccess;
@@ -186,4 +187,4 @@ public abstract class FileDocumentManager implements SavingRequestor {
     @NotNull
     public String getReadOnlyMessage() {return myReadOnlyMessage;}
   }
-}
+}
\ No newline at end of file
diff --git a/platform/core-api/src/com/intellij/openapi/fileTypes/BinaryFileDecompiler.java b/platform/core-api/src/com/intellij/openapi/fileTypes/BinaryFileDecompiler.java
index 3e9b7e1472c2..2e952c74dba6 100644
--- a/platform/core-api/src/com/intellij/openapi/fileTypes/BinaryFileDecompiler.java
+++ b/platform/core-api/src/com/intellij/openapi/fileTypes/BinaryFileDecompiler.java
@@ -1,28 +1,12 @@
-/*
- * Copyright 2000-2009 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.
- */
-
-/*
- * @author max
- */
+// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.openapi.fileTypes;
 
 import com.intellij.openapi.vfs.VirtualFile;
 import org.jetbrains.annotations.NotNull;
 
+/**
+ * @author max
+ */
 public interface BinaryFileDecompiler {
-  @NotNull
-  CharSequence decompile(@NotNull VirtualFile file);
+  @NotNull CharSequence decompile(@NotNull VirtualFile file);
 }
\ No newline at end of file
diff --git a/platform/core-api/src/com/intellij/psi/stubs/BinaryFileStubBuilder.java b/platform/core-api/src/com/intellij/psi/stubs/BinaryFileStubBuilder.java
index e726b6d92bac..ef1bb8e9b8ed 100644
--- a/platform/core-api/src/com/intellij/psi/stubs/BinaryFileStubBuilder.java
+++ b/platform/core-api/src/com/intellij/psi/stubs/BinaryFileStubBuilder.java
@@ -1,22 +1,4 @@
-/*
- * 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.
- */
-
-/*
- * @author max
- */
+// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.psi.stubs;
 
 import com.intellij.openapi.vfs.VirtualFile;
@@ -26,30 +8,27 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.stream.Stream;
 
+/**
+ * @author max
+ */
 public interface BinaryFileStubBuilder {
   boolean acceptsFile(@NotNull VirtualFile file);
 
-  @Nullable
-  Stub buildStubTree(@NotNull FileContent fileContent);
+  @Nullable Stub buildStubTree(@NotNull FileContent fileContent);
 
   int getStubVersion();
 
   interface CompositeBinaryFileStubBuilder<SubBuilder> extends BinaryFileStubBuilder {
-    @NotNull
-    Stream<SubBuilder> getAllSubBuilders();
+    @NotNull Stream<SubBuilder> getAllSubBuilders();
 
-    @Nullable
-    SubBuilder getSubBuilder(@NotNull FileContent fileContent);
+    @Nullable SubBuilder getSubBuilder(@NotNull FileContent fileContent);
 
-    @NotNull
-    String getSubBuilderVersion(@Nullable SubBuilder subBuilder);
+    @NotNull String getSubBuilderVersion(@Nullable SubBuilder subBuilder);
 
-    @Nullable
-    Stub buildStubTree(@NotNull FileContent fileContent, @Nullable SubBuilder builder);
+    @Nullable Stub buildStubTree(@NotNull FileContent fileContent, @Nullable SubBuilder builder);
 
-    @Nullable
     @Override
-    default Stub buildStubTree(@NotNull FileContent fileContent) {
+    default @Nullable Stub buildStubTree(@NotNull FileContent fileContent) {
       return buildStubTree(fileContent, getSubBuilder(fileContent));
     }
   }
diff --git a/platform/platform-api/resources/messages/IdeBundle.properties b/platform/platform-api/resources/messages/IdeBundle.properties
index 50b238976048..924b5e164017 100644
--- a/platform/platform-api/resources/messages/IdeBundle.properties
+++ b/platform/platform-api/resources/messages/IdeBundle.properties
@@ -2065,7 +2065,7 @@ welcome.screen.empty.projects.create.comment= Create a new project to start from
 welcome.screen.empty.projects.open.comment=Open existing project from disk or version control.
 welcome.screen.empty.projects.more.text=More Actions
 
-progress.title.file.system.synchronization=File System Synchronization
+progress.title.file.system.synchronization=File system synchronization
 progress.text.processing.detected.file.changes=Processing {0} detected file {0,choice,1#change|2#changes}...
 popup.title.add.run.options=Add Run Options
 dialog.message.new.name=New {0} name:
diff --git a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileDocumentManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileDocumentManagerImpl.java
index 87553bfd2898..434785376914 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileDocumentManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileEditor/impl/FileDocumentManagerImpl.java
@@ -883,6 +883,7 @@ public class FileDocumentManagerImpl extends FileDocumentManager implements Safe
 
   /** @deprecated another dirty Rider hack; don't use */
   @Deprecated
+  @SuppressWarnings("StaticNonFinalField")
   public static boolean ourConflictsSolverEnabled = true;
 
   protected void cacheDocument(@NotNull VirtualFile file, @NotNull Document document) {
diff --git a/platform/platform-impl/src/com/intellij/openapi/vfs/newvfs/RefreshSessionImpl.java b/platform/platform-impl/src/com/intellij/openapi/vfs/newvfs/RefreshSessionImpl.java
index ee8991148f52..79cfb4d00708 100644
--- a/platform/platform-impl/src/com/intellij/openapi/vfs/newvfs/RefreshSessionImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/vfs/newvfs/RefreshSessionImpl.java
@@ -54,11 +54,8 @@ class RefreshSessionImpl extends RefreshSession {
   }
 
   private Throwable rememberStartTrace() {
-    if (ApplicationManager.getApplication().isUnitTestMode() &&
-        (myIsAsync || !ApplicationManager.getApplication().isDispatchThread())) {
-      return new Throwable();
-    }
-    return null;
+    boolean trace = ApplicationManager.getApplication().isUnitTestMode() && (myIsAsync || !ApplicationManager.getApplication().isDispatchThread());
+    return trace ? new Throwable() : null;
   }
 
   RefreshSessionImpl(@NotNull List<? extends VFileEvent> events) {