org.apache.hadoop.dfs
Interfaces 
FSConstants
Classes 
DataNode
DatanodeDescriptor
DatanodeID
DatanodeInfo
DFSAdmin
DFSck
DistributedFileSystem
FsckServlet
GetImageServlet
JspHelper
NameNode
NamenodeFsck
SecondaryNameNode
SecondaryNameNode.GetImageServlet
StreamFile
Enums 
DatanodeInfo.AdminStates
FSConstants.NodeType
FSConstants.SafeModeAction
FSConstants.StartupOption
Exceptions 
AlreadyBeingCreatedException
LeaseExpiredException
NotReplicatedYetException
SafeModeException