org.apache.hadoop.fs
Interfaces 
FileStatus
PathFilter
PositionedReadable
Seekable
Classes 
BufferedFSInputStream
ChecksumFileSystem
Command
DF
FileSystem
FileUtil
FileUtil.HardLink
FilterFileSystem
FSDataInputStream
FSDataOutputStream
FSInputChecker
FSInputStream
FSOutputSummer
FsShell
InMemoryFileSystem
LocalDirAllocator
LocalFileSystem
Path
RawLocalFileSystem
Trash
Exceptions 
ChecksumException
Errors 
FSError