[HDFS-14598] Findbugs warning caused by HDFS-12487

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.3.0, 3.2.1, 3.1.3
• Component/s: diskbalancer
• Labels: newbie
• Hadoop Flags: Reviewed
• Assignee: Xiaoqiao He
• Reporter: Wei-Chiu Chuang
• Created: 24/Jun/19 00:05
• Updated: 02/Oct/19 17:15
• Resolved: 25/Jun/19 02:08

Description

https://builds.apache.org/job/PreCommit-HDFS-Build/27038/artifact/out/branch-findbugs-hadoop-hdfs-project_hadoop-hdfs-warnings.html

Redundant nullcheck of block, which is known to be non-null in org.apache.hadoop.hdfs.server.datanode.DiskBalancer$DiskBalancerMover.getBlockToCopy(FsVolumeSpi$BlockIterator, DiskBalancerWorkItem)
Bug type RCN_REDUNDANT_NULLCHECK_OF_NONNULL_VALUE (click for details) 
In class org.apache.hadoop.hdfs.server.datanode.DiskBalancer$DiskBalancerMover
In method org.apache.hadoop.hdfs.server.datanode.DiskBalancer$DiskBalancerMover.getBlockToCopy(FsVolumeSpi$BlockIterator, DiskBalancerWorkItem)
Value loaded from block
Return value of org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeSpi$BlockIterator.nextBlock() of type org.apache.hadoop.hdfs.protocol.ExtendedBlock
Redundant null check at DiskBalancer.java:[line 912]