From 31bbae96c57da1059b5e90c1d188025c6a3bcb2c Mon Sep 17 00:00:00 2001
From: Xiaoyu Yao <xyao@apache.org>
Date: Thu, 14 Sep 2017 14:54:16 -0700
Subject: [PATCH] HDFS-12426. Ozone: BlockManager MBean unregister failure upon
 shutdown. Contributed by Lokesh Jain.

---
 .../apache/hadoop/ozone/scm/block/BlockManagerImpl.java    | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/block/BlockManagerImpl.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/block/BlockManagerImpl.java
index 472dc7d08d7..23b1c8bdd2f 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/block/BlockManagerImpl.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/block/BlockManagerImpl.java
@@ -105,7 +105,7 @@ public class BlockManagerImpl implements BlockManager, BlockmanagerMXBean {
       Map<String, BlockContainerInfo>> containers;
   private final int containerProvisionBatchSize;
   private final Random rand;
-  private final ObjectName mxBean;
+  private ObjectName mxBean;
 
 
   /**
@@ -588,7 +588,10 @@ public void close() throws IOException {
       deletedBlockLog.close();
     }
     blockDeletingService.shutdown();
-    MBeans.unregister(mxBean);
+    if (mxBean != null) {
+      MBeans.unregister(mxBean);
+      mxBean = null;
+    }
   }
 
   @Override