Package org.apache.hadoop.hdfs.protocol

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Interface Summary

Interface	Description
ClientDatanodeProtocol	An client-datanode protocol for block recovery
ClientProtocol	ClientProtocol is used by user code via the DistributedFileSystem class to communicate with the NameNode.
HdfsFileStatus	HDFS metadata for an entity in the filesystem.
ReconfigurationProtocol	ReconfigurationProtocol is used by HDFS admin to reload configuration for NN/DN without restarting them.

Class Summary

Class	Description
AddErasureCodingPolicyResponse	A response of add an ErasureCoding policy.
BatchedDirectoryListing	A struct-like class for holding partial listings returned by the batched listing API.
Block	A Block is a Hadoop FS primitive, identified by its block ID (a long).
BlockChecksumOptions	Encapsulates various options related to how fine-grained data checksums are combined into block-level checksums.
BlockLocalPathInfo	A block and the full path information to the block data file and the metadata file stored on the local file system.
BlockStoragePolicy	A block storage policy describes how to select the storage types for the replicas of a block.
CacheDirectiveEntry	Describes a path-based cache directive entry.
CacheDirectiveInfo	Describes a path-based cache directive.
CacheDirectiveInfo.Builder	A builder for creating new CacheDirectiveInfo instances.
CacheDirectiveInfo.Expiration	Denotes a relative or absolute expiration time for a CacheDirective.
CacheDirectiveIterator	CacheDirectiveIterator is a remote iterator that iterates cache directives.
CacheDirectiveStats	Describes a path-based cache directive.
CacheDirectiveStats.Builder
CachePoolEntry	Describes a Cache Pool entry.
CachePoolInfo	CachePoolInfo describes a cache pool.
CachePoolIterator	CachePoolIterator is a remote iterator that iterates cache pools.
CachePoolStats	CachePoolStats describes cache pool statistics.
CachePoolStats.Builder
CorruptFileBlocks	Contains a list of paths corresponding to corrupt files and a cookie used for iterative calls to NameNode.listCorruptFileBlocks.
DatanodeAdminProperties	The class describes the configured admin properties for a datanode.
DatanodeID	This class represents the primary identifier for a Datanode.
DatanodeInfo	This class extends the primary identifier of a Datanode with ephemeral state, eg usage information, current administrative state, and the network location that is communicated to clients.
DatanodeInfo.DatanodeInfoBuilder	Building the DataNodeInfo.
DatanodeInfoWithStorage
DatanodeLocalInfo	Locally available datanode information
DatanodeVolumeInfo	Locally available datanode volume information.
DirectoryListing	This class defines a partial listing of a directory to support iterative directory listing.
ECBlockGroupStats	Get statistics pertaining to blocks of type BlockType.STRIPED in the filesystem.
ECTopologyVerifierResult	Result of the verification whether the current cluster setup can support all enabled EC policies.
EncryptionZone	A simple class for representing an encryption zone.
EncryptionZoneIterator	EncryptionZoneIterator is a remote iterator that iterates over encryption zones.
ErasureCodingPolicy	A policy about how to write/read/code an erasure coding file.
ErasureCodingPolicyInfo	HDFS internal presentation of a ErasureCodingPolicy.
ExtendedBlock	Identifies a Block uniquely across the block pools
FsPermissionExtension	Deprecated. ACLs, encryption, and erasure coding are managed on FileStatus.
HdfsConstants
HdfsFileStatus.Builder	Builder class for HdfsFileStatus instances.
HdfsLocatedFileStatus	HDFS metadata for an entity in the filesystem with locations.
HdfsNamedFileStatus	HDFS metadata for an entity in the filesystem without locations.
HdfsPartialListing	A partial listing returned by the batched listing API.
HdfsPathHandle	Opaque handle to an entity in HDFS.
LastBlockWithStatus	Class to contain Lastblock and HdfsFileStatus for the Append operation
LocatedBlock	Associates a block with the Datanodes that contain its replicas and other block metadata (E.g.
LocatedBlocks	Collection of blocks with their locations and the file length.
LocatedStripedBlock	LocatedBlock with striped block support.
OpenFileEntry	An open file entry for use by DFSAdmin commands.
OpenFilesIterator	OpenFilesIterator is a remote iterator that iterates over the open files list managed by the NameNode.
ProvidedStorageLocation	ProvidedStorageLocation is a location in an external storage system containing the data for a block (~Replica).
ReencryptionStatus	A class representing information about re-encrypting encryption zones.
ReencryptionStatusIterator	ReencryptionStatusIterator is a remote iterator that iterates over the reencryption status of encryption zones.
ReplicatedBlockStats	Get statistics pertaining to blocks of type BlockType.CONTIGUOUS in the filesystem.
RollingUpgradeInfo	Rolling upgrade information
RollingUpgradeInfo.Bean
RollingUpgradeStatus	Rolling upgrade status
SnapshotDiffReport	This class represents to end users the difference between two snapshots of the same directory, or the difference between a snapshot of the directory and its current state.
SnapshotDiffReport.DiffReportEntry	Representing the full path and diff type of a file/directory where changes have happened.
SnapshotDiffReport.DiffStats	Records the stats related to Snapshot diff operation.
SnapshotDiffReportListing	This class represents to the difference between two snapshots of the same directory, or the difference between a snapshot of the directory and its current state.
SnapshotDiffReportListing.DiffReportListingEntry	Representing the full path and diff type of a file/directory where changes have happened.
SnapshotStatus	Metadata about a snapshottable directory.
SnapshottableDirectoryStatus	Metadata about a snapshottable directory
SnapshottableDirectoryStatus.Bean
StripedBlockInfo	Striped block info that can be sent elsewhere to do block group level things, like checksum, and etc.
SystemErasureCodingPolicies	The set of built-in erasure coding policies.
ZoneReencryptionStatus	A class representing information about re-encryption of an encryption zone.
ZoneReencryptionStatus.Builder	Builder of ZoneReencryptionStatus.

Enum Summary

Enum	Description
BlockChecksumType	Algorithms/types denoting how block-level checksums are computed using lower-level chunk checksums/CRCs.
BlockType	Type of a block.
DatanodeInfo.AdminStates
ErasureCodingPolicyState	Value denotes the possible states of an ErasureCodingPolicy.
HdfsConstants.DatanodeReportType
HdfsConstants.ReencryptAction	Re-encrypt encryption zone actions.
HdfsConstants.RollingUpgradeAction
HdfsConstants.SafeModeAction
HdfsConstants.StoragePolicy	This enum wraps above Storage Policy ID and name.
HdfsConstants.StoragePolicySatisfierMode	Storage policy satisfier service modes.
HdfsConstants.UpgradeAction	Upgrade actions.
HdfsFileStatus.Flags	Set of features potentially active on an instance.
OpenFilesIterator.OpenFilesType	Open file types to filter the results.
SnapshotDiffReport.DiffType	Types of the difference, which include CREATE, MODIFY, DELETE, and RENAME.
ZoneReencryptionStatus.State	State of re-encryption.

Exception Summary

Exception	Description
AclException	Indicates a failure manipulating an ACL.
AlreadyBeingCreatedException	The exception that happens when you ask to create a file that already is being created, but is not closed yet.
DSQuotaExceededException
NoECPolicySetException	Thrown when no EC policy is set explicitly on the directory.
NSQuotaExceededException
QuotaByStorageTypeExceededException
QuotaExceededException	This exception is thrown when modification to HDFS results in violation of a directory quota.
SnapshotAccessControlException	Snapshot access related exception.
UnresolvedPathException	Thrown when a symbolic link is encountered in a path.
XAttrNotFoundException	The exception that happens when you ask to get a non existing XAttr.