Package org.apache.hadoop.hdfs.server.namenode.snapshot

Class DirectorySnapshottableFeature

java.lang.Object

org.apache.hadoop.hdfs.server.namenode.snapshot.DirectoryWithSnapshotFeature

org.apache.hadoop.hdfs.server.namenode.snapshot.DirectorySnapshottableFeature

All Implemented Interfaces:

INode.Feature

@Private
public class DirectorySnapshottableFeature
extends DirectoryWithSnapshotFeature

A directory with this feature is a snapshottable directory, where snapshots can be taken. This feature extends DirectoryWithSnapshotFeature, and maintains extra information about all the snapshots taken on this directory.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hdfs.server.namenode.snapshot.DirectoryWithSnapshotFeature

DirectoryWithSnapshotFeature.DirectoryDiff, DirectoryWithSnapshotFeature.DirectoryDiffList

Constructor Summary

Constructors

Constructor	Description
DirectorySnapshottableFeature(DirectoryWithSnapshotFeature feature)

Method Summary

Modifier and Type	Method	Description
Snapshot	addSnapshot(INodeDirectory snapshotRoot, SnapshotManager snapshotManager, java.lang.String name, LeaseManager leaseManager, long now)	Add a snapshot.
void	computeContentSummary4Snapshot(BlockStoragePolicySuite bsps, ContentCounts counts)
void	dumpTreeRecursively(INodeDirectory snapshotRoot, java.io.PrintWriter out, java.lang.StringBuilder prefix, int snapshot)
byte[][]	findRenameTargetPath(INodeDirectory snapshotRoot, INodeReference.WithName wn, int snapshotId)	We just found a deleted WithName node as the source of a rename operation.
int	getNumSnapshots()
Snapshot	getSnapshot(byte[] snapshotName)
Snapshot	getSnapshotById(int sid)
Snapshot	getSnapshotByName(INodeDirectory snapshotRoot, java.lang.String snapshotName)	Find the snapshot matching the given name.
ReadOnlyList<Snapshot>	getSnapshotList()
int	getSnapshotQuota()
Snapshot	removeSnapshot(INode.ReclaimContext reclaimContext, INodeDirectory snapshotRoot, java.lang.String snapshotName, long now, SnapshotManager snapshotManager)	Remove the snapshot with the given name from snapshotsByNames, and delete all the corresponding DirectoryDiff.
void	renameSnapshot(java.lang.String path, java.lang.String oldName, java.lang.String newName, long mtime)	Rename a snapshot
void	setSnapshotQuota(int snapshotQuota)
java.lang.String	toString()

Methods inherited from class org.apache.hadoop.hdfs.server.namenode.snapshot.DirectoryWithSnapshotFeature

addChild, cleanDirectory, clear, computeQuotaUsage4CurrentDirectory, destroyDstSubtree, getChild, getChildrenList, getDiffs, getLastSnapshotId, getSnapshotDirectory, removeChild, saveChild2Snapshot

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

DirectorySnapshottableFeature

public DirectorySnapshottableFeature(DirectoryWithSnapshotFeature feature)

Method Detail

getNumSnapshots

public int getNumSnapshots()

Returns:

the number of existing snapshots.

getSnapshot

public Snapshot getSnapshot(byte[] snapshotName)

Returns:

the snapshot with the given name.

getSnapshotById

public Snapshot getSnapshotById(int sid)

getSnapshotList

public ReadOnlyList<Snapshot> getSnapshotList()

Returns:

snapshotsByNames as a ReadOnlyList

renameSnapshot

public void renameSnapshot(java.lang.String path,
                           java.lang.String oldName,
                           java.lang.String newName,
                           long mtime)
                    throws SnapshotException

Rename a snapshot

Parameters:

path - The directory path where the snapshot was taken. Used for generating exception message.

oldName - Old name of the snapshot

newName - New name the snapshot will be renamed to

mtime - The snapshot modification time set by Time.now().

Throws:

SnapshotException - Throw SnapshotException when either the snapshot with the old name does not exist or a snapshot with the new name already exists

getSnapshotQuota

public int getSnapshotQuota()

setSnapshotQuota

public void setSnapshotQuota(int snapshotQuota)

addSnapshot

public Snapshot addSnapshot(INodeDirectory snapshotRoot,
                            SnapshotManager snapshotManager,
                            java.lang.String name,
                            LeaseManager leaseManager,
                            long now)
                     throws SnapshotException

Add a snapshot.

Parameters:

snapshotRoot - Root of the snapshot.

snapshotManager - SnapshotManager Instance.

name - Name of the snapshot.

leaseManager -

Throws:

SnapshotException - Throw SnapshotException when there is a snapshot with the same name already exists or snapshot quota exceeds

removeSnapshot

public Snapshot removeSnapshot(INode.ReclaimContext reclaimContext,
                               INodeDirectory snapshotRoot,
                               java.lang.String snapshotName,
                               long now,
                               SnapshotManager snapshotManager)
                        throws SnapshotException

Remove the snapshot with the given name from snapshotsByNames, and delete all the corresponding DirectoryDiff.

Parameters:

reclaimContext - records blocks and inodes that need to be reclaimed

snapshotRoot - The directory where we take snapshots

snapshotName - The name of the snapshot to be removed

now - The snapshot deletion time set by Time.now().

Returns:

The removed snapshot. Null if no snapshot with the given name exists.

Throws:

SnapshotException

computeContentSummary4Snapshot

public void computeContentSummary4Snapshot(BlockStoragePolicySuite bsps,
                                           ContentCounts counts)
                                    throws org.apache.hadoop.security.AccessControlException

Overrides:

computeContentSummary4Snapshot in class DirectoryWithSnapshotFeature

Throws:

org.apache.hadoop.security.AccessControlException

getSnapshotByName

public Snapshot getSnapshotByName(INodeDirectory snapshotRoot,
                                  java.lang.String snapshotName)
                           throws SnapshotException

Find the snapshot matching the given name.

Parameters:

snapshotRoot - The directory where snapshots were taken.

snapshotName - The name of the snapshot.

Returns:

The corresponding snapshot. Null if snapshotName is null or empty.

Throws:

SnapshotException - If snapshotName is not null or empty, but there is no snapshot matching the name.

findRenameTargetPath

public byte[][] findRenameTargetPath(INodeDirectory snapshotRoot,
                                     INodeReference.WithName wn,
                                     int snapshotId)

We just found a deleted WithName node as the source of a rename operation. However, we should include it in our snapshot diff report as rename only if the rename target is also under the same snapshottable directory.

toString

public java.lang.String toString()

Overrides:

toString in class DirectoryWithSnapshotFeature

dumpTreeRecursively

@VisibleForTesting
public void dumpTreeRecursively(INodeDirectory snapshotRoot,
                                java.io.PrintWriter out,
                                java.lang.StringBuilder prefix,
                                int snapshot)