[HDFS-5987] Fix findbugs warnings in Rolling Upgrade branch

• Type: Sub-task
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: HDFS-5535 (Rolling upgrades)
• Component/s: datanode, ha, hdfs-client, namenode
• Target Version/s: HDFS-5535 (Rolling upgrades)
• Hadoop Flags: Reviewed
• Assignee: Tsz-wo Sze
• Reporter: Tsz-wo Sze
• Created: 20/Feb/14 22:21
• Updated: 20/Feb/14 23:21
• Resolved: 20/Feb/14 23:21

Description

RV 	org.apache.hadoop.hdfs.server.datanode.BlockPoolSliceStorage.restoreBlockFilesFromTrash(File) ignores exceptional return value of java.io.File.mkdirs()
RV 	org.apache.hadoop.hdfs.server.datanode.BlockPoolSliceStorage.restoreBlockFilesFromTrash(File) ignores exceptional return value of java.io.File.renameTo(File)
RV 	org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetAsyncDiskService$ReplicaFileDeleteTask.moveFiles() ignores exceptional return value of java.io.File.mkdirs()
IS 	Inconsistent synchronization of org.apache.hadoop.hdfs.qjournal.server.Journal.committedTxnId; locked 92% of time
NP 	Dereference of the result of readLine() without nullcheck in org.apache.hadoop.hdfs.util.MD5FileUtils.renameMD5File(File, File)