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

Interface NamespaceVisitor

All Known Implementing Classes:

INodeCountVisitor, NamespacePrintVisitor

public interface NamespaceVisitor

For visiting namespace trees.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	NamespaceVisitor.Element	Snapshot and INode.
static interface	NamespaceVisitor.INodeVisitor	For visiting any INode.

Method Summary

Modifier and Type	Method	Description
static Iterable<NamespaceVisitor.Element>	getChildren(INodeDirectory dir, int snapshot)
default NamespaceVisitor.INodeVisitor	getDefaultVisitor()
static Iterable<NamespaceVisitor.Element>	getSnapshots(DirectorySnapshottableFeature snapshottable)
default void	postVisitReferred(INode referred)	Right after visiting the given referred INode.
default void	postVisitSub(NamespaceVisitor.Element sub, int index, boolean isLast)	Right after visiting the given sub NamespaceVisitor.Element.
default void	preVisitReferred(INode referred)	Right before visiting the given referred INode.
default void	preVisitSub(NamespaceVisitor.Element sub, int index, boolean isLast)	Right before visiting the given sub NamespaceVisitor.Element.
default void	visitDirectory(INodeDirectory dir, int snapshot)	Visiting the given INodeDirectory (non-recursively).
default void	visitDirectoryRecursively(INodeDirectory dir, int snapshot)	First visit the given INodeDirectory; then the children; and then, if snapshottable, the snapshots.
default void	visitFile(INodeFile file, int snapshot)	Visiting the given INodeFile.
default void	visitReference(INodeReference ref, int snapshot)	Visiting the given INodeReference (non-recursively).
default void	visitReferenceRecursively(INodeReference ref, int snapshot)	First visit the given INodeReference and then the referred.
default void	visitSnapshottable(INodeDirectory dir, DirectorySnapshottableFeature snapshottable)	Visiting a DirectorySnapshottableFeature.
default void	visitSubs(Iterable<NamespaceVisitor.Element> subs)	Visiting the sub NamespaceVisitor.Elements recursively.
default void	visitSymlink(INodeSymlink symlink, int snapshot)	Visiting the given INodeSymlink.

Method Details

getDefaultVisitor

default NamespaceVisitor.INodeVisitor getDefaultVisitor()

Returns:

the default (non-recursive) NamespaceVisitor.INodeVisitor.

visitFile

default void visitFile(INodeFile file,
 int snapshot)

Visiting the given INodeFile.

visitSymlink

default void visitSymlink(INodeSymlink symlink,
 int snapshot)

Visiting the given INodeSymlink.

visitReference

default void visitReference(INodeReference ref,
 int snapshot)

Visiting the given INodeReference (non-recursively).

visitReferenceRecursively

default void visitReferenceRecursively(INodeReference ref,
 int snapshot)

First visit the given INodeReference and then the referred.

preVisitReferred

default void preVisitReferred(INode referred)

Right before visiting the given referred INode.

postVisitReferred

default void postVisitReferred(INode referred)

Right after visiting the given referred INode.

visitDirectory

default void visitDirectory(INodeDirectory dir,
 int snapshot)

Visiting the given INodeDirectory (non-recursively).

visitDirectoryRecursively

default void visitDirectoryRecursively(INodeDirectory dir,
 int snapshot)

First visit the given INodeDirectory; then the children; and then, if snapshottable, the snapshots.

preVisitSub

default void preVisitSub(NamespaceVisitor.Element sub,
 int index,
 boolean isLast)

Right before visiting the given sub NamespaceVisitor.Element. The sub element may be a child of an INodeDirectory or a snapshot in DirectorySnapshottableFeature.

Parameters:

sub - the element to be visited.

index - the index of the sub element.

isLast - is the sub element the last element?

postVisitSub

default void postVisitSub(NamespaceVisitor.Element sub,
 int index,
 boolean isLast)

Right after visiting the given sub NamespaceVisitor.Element. The sub element may be a child of an INodeDirectory or a snapshot in DirectorySnapshottableFeature.

Parameters:

sub - the element just visited.

index - the index of the sub element.

isLast - is the sub element the last element?

visitSnapshottable

default void visitSnapshottable(INodeDirectory dir,
 DirectorySnapshottableFeature snapshottable)

Visiting a DirectorySnapshottableFeature.

visitSubs

default void visitSubs(Iterable<NamespaceVisitor.Element> subs)

Visiting the sub NamespaceVisitor.Elements recursively.

Parameters:

subs - the children of an INodeDirectory or the snapshots in DirectorySnapshottableFeature.

getChildren

static Iterable<NamespaceVisitor.Element> getChildren(INodeDirectory dir,
 int snapshot)

Returns:

the children as NamespaceVisitor.Elements.

getSnapshots

static Iterable<NamespaceVisitor.Element> getSnapshots(DirectorySnapshottableFeature snapshottable)

Returns:

the snapshots as NamespaceVisitor.Elements.