Package org.apache.hadoop.hdfs.server.common

Interface Summary

Interface	Description
BlockAlias	Interface used to load provided blocks.
DataNodeLockManager<T extends AutoCloseDataSetLock>	Use for manage a set of lock for datanode.
HdfsServerConstants	Some handy internal HDFS constants
HostRestrictingAuthorizationFilter.HttpInteraction
Storage.FormatConfirmable	Interface for classes which need to have the user confirm their formatting during NameNode -format and other similar operations.
Storage.StorageDirType	An interface to denote storage directory type Implementations can define a type for storage directory by implementing this interface.
StorageErrorReporter	Interface which implementations of JournalManager can use to report errors on underlying storage directories.
TokenVerifier<T extends org.apache.hadoop.security.token.delegation.AbstractDelegationTokenIdentifier>	Interface to verify delegation tokens passed through WebHDFS.

Class Summary

Class	Description
AutoCloseDataSetLock	Extending AutoCloseableLock such that the users can use a try-with-resource syntax.
ECTopologyVerifier	Class for verifying whether the cluster setup can support all enabled EC policies.
FileRegion	This class is used to represent provided blocks that are file regions, i.e., can be described using (path, offset, length).
GenerationStamp	A GenerationStamp is a Hadoop FS primitive, identified by a long.
HostRestrictingAuthorizationFilter	An HTTP filter that can filter requests based on Hosts.
JspHelper
MetricsLoggerTask	MetricsLoggerTask can be used as utility to dump metrics to log.
NoLockManager	Some ut or temp replicaMap not need to lock with DataSetLockManager.
Storage	Storage information file.
Storage.StorageDirectory	One of the storage directories.
StorageInfo	Common class for storage information.
Util

Enum Summary

Enum	Description
DataNodeLockManager.LockLevel	Acquire block pool level first if you want to Acquire volume lock.
HdfsServerConstants.BlockUCState	States, which a block can go through while it is under construction.
HdfsServerConstants.NamenodeRole	Defines the NameNode role.
HdfsServerConstants.NodeType	Type of the node
HdfsServerConstants.ReplicaState	Block replica states, which it can go through while being constructed.
HdfsServerConstants.RollingUpgradeStartupOption	Startup options for rolling upgrade.
HdfsServerConstants.StartupOption	Startup options
Storage.StorageState

Exception Summary

Exception	Description
HttpGetFailedException
HttpPutFailedException
InconsistentFSStateException	The exception is thrown when file system state is inconsistent and is not recoverable.
IncorrectVersionException	The exception is thrown when external version does not match current version of the application.