diff --git a/java/java-impl/src/com/intellij/openapi/keymap/JBuilderKeymapProvider.java b/java/java-impl/src/com/intellij/openapi/keymap/JBuilderKeymapProvider.java
index 5386c7d2e1f0..430742591302 100644
--- a/java/java-impl/src/com/intellij/openapi/keymap/JBuilderKeymapProvider.java
+++ b/java/java-impl/src/com/intellij/openapi/keymap/JBuilderKeymapProvider.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 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.
@@ -16,6 +16,7 @@
 package com.intellij.openapi.keymap;
 
 import com.intellij.openapi.keymap.impl.BundledKeymapProvider;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.Collections;
 import java.util.List;
@@ -24,6 +25,7 @@ import java.util.List;
  * @author yole
  */
 public class JBuilderKeymapProvider implements BundledKeymapProvider {
+  @NotNull
   @Override
   public List<String> getKeymapFileNames() {
     return Collections.singletonList("JBuilder.xml");
diff --git a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/BundledKeymapProvider.java b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/BundledKeymapProvider.java
index 2b205421b84a..9ed011b207aa 100644
--- a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/BundledKeymapProvider.java
+++ b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/BundledKeymapProvider.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 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.
@@ -16,6 +16,7 @@
 package com.intellij.openapi.keymap.impl;
 
 import com.intellij.openapi.extensions.ExtensionPointName;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
@@ -26,5 +27,6 @@ import java.util.List;
 public interface BundledKeymapProvider {
   ExtensionPointName<BundledKeymapProvider> EP_NAME = ExtensionPointName.create("com.intellij.bundledKeymapProvider");
 
+  @NotNull
   List<String> getKeymapFileNames();
 }
diff --git a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultBundledKeymaps.java b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultBundledKeymaps.java
index a27961487b01..aa968278f741 100644
--- a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultBundledKeymaps.java
+++ b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultBundledKeymaps.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 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.
@@ -19,10 +19,13 @@
  */
 package com.intellij.openapi.keymap.impl;
 
+import org.jetbrains.annotations.NotNull;
+
 import java.util.Arrays;
 import java.util.List;
 
 public class DefaultBundledKeymaps implements BundledKeymapProvider {
+  @NotNull
   @Override
   public List<String> getKeymapFileNames() {
     return Arrays.asList(
diff --git a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultKeymap.kt b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultKeymap.kt
index 4d6a2f53c087..d3862866ed4c 100644
--- a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultKeymap.kt
+++ b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/DefaultKeymap.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 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.
@@ -65,7 +65,9 @@ open class DefaultKeymap {
 
         LOG.catchAndLog {
           loadKeymapsFromElement(object: SchemeDataHolder<KeymapImpl> {
-            override fun read() = JDOMUtil.loadResourceDocument(URL("file:///keymaps/$key")).rootElement
+            override fun read(): Element {
+              return JDOMUtil.loadResourceDocument(URL("file:///keymaps/$key")).rootElement
+            }
 
             override fun updateDigest(scheme: KeymapImpl) {
             }
diff --git a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/GenericKeymapManager.java b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/GenericKeymapManager.java
index 4106fb7e86ee..e67b26440d09 100644
--- a/platform/platform-impl/src/com/intellij/openapi/keymap/impl/GenericKeymapManager.java
+++ b/platform/platform-impl/src/com/intellij/openapi/keymap/impl/GenericKeymapManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2015 JetBrains s.r.o.
+ * Copyright 2000-2017 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.
@@ -20,6 +20,7 @@ import com.intellij.openapi.util.SystemInfo;
 import org.jetbrains.annotations.NotNull;
 
 public class GenericKeymapManager extends DefaultKeymap {
+  @NotNull
   @Override
   public String getDefaultKeymapName() {
     if (SystemInfo.isMac) {
@@ -33,6 +34,7 @@ public class GenericKeymapManager extends DefaultKeymap {
     }
   }
 
+  @NotNull
   @Override
   public String getKeymapPresentableName(@NotNull KeymapImpl keymap) {
     final String name = keymap.getName();