org.apache.hadoop.hdfs.server.protocol
Classes 
BalancerBandwidthCommand
DatanodeStorage
ReceivedDeletedBlockInfo
RemoteEditLog
RemoteEditLogManifest
StorageBlockReport
StorageReceivedDeletedBlocks
StorageReport
Enums 
DatanodeStorage.State
ReceivedDeletedBlockInfo.BlockStatus
Exceptions 
FencedException