Package org.apache.hadoop.hdfs

A distributed implementation of FileSystem.

See:
Description

Interface Summary

BlockReader	A BlockReader is responsible for reading a single block from a single datanode.
RemotePeerFactory

Class Summary

BlockReaderFactory.BlockReaderPeer
CorruptFileBlockIterator	Provides an iterator interface for listCorruptFileBlocks.
DFSClient.Conf	DFSClient configuration
DFSClient.DFSDataInputStream	Deprecated. use HdfsDataInputStream instead.
DFSHedgedReadMetrics	The client-side metrics for hedged read feature.
DFSInotifyEventInputStream	Stream for reading inotify events.
DFSInputStream.ReadStatistics
DFSUtil.ConfiguredNNAddress	Represent one of the NameNodes configured in the cluster.
ExtendedBlockId	An immutable key which identifies a block.
HAUtil
NameNodeProxies	Create proxy objects to communicate with a remote NN.
NameNodeProxies.ProxyAndInfo<PROXYTYPE>	Wrapper for a client proxy as well as its associated service ID.

Enum Summary

StorageType

Defines the types of supported storage media.

Exception Summary

UnknownCipherSuiteException	Thrown when an unknown cipher suite is encountered.
UnknownCryptoProtocolVersionException

Package org.apache.hadoop.hdfs Description

A distributed implementation of FileSystem. This is loosely modelled after Google's GFS.

The most important difference is that unlike GFS, Hadoop DFS files have strictly one writer at any one time. Bytes are always appended to the end of the writer's stream. There is no notion of "record appends" or "mutations" that are then checked or reordered. Writers simply emit a byte stream. That byte stream is guaranteed to be stored in the order written.