YARN-4167. NPE on RMActiveServices#serviceStop when store is null. (Bibin A Chundatt via rohithsharmaks)

Backport YARN-6633 by Inigo Goiri.

(cherry picked from commit c9cb6a5960ad335a3ee93a6ee219eae5aad372f9)

hadoop-yarn-project/CHANGES.txt

@@ -19,6 +19,10 @@ Release 2.7.6 - UNRELEASED
     NodeLabelsManager.serviceInit failed. (Bibin A Chundatt via wangda)
     Backport YARN-6632 by Inigo Goiri.
 
+    YARN-4167. NPE on RMActiveServices#serviceStop when store is null.
+    (Bibin A Chundatt via rohithsharmaks)
+    Backport YARN-6633 by Inigo Goiri.
+
 Release 2.7.5 - 2017-12-14
 
   INCOMPATIBLE CHANGES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/ResourceManager.java

@@ -592,7 +592,9 @@ public class ResourceManager extends CompositeService implements Recoverable {
       if (rmContext != null) {
         RMStateStore store = rmContext.getStateStore();
         try {
-          store.close();
+          if (null != store) {
+            store.close();
+          }
         } catch (Exception e) {
           LOG.error("Error closing store.", e);
         }