org.apache.hadoop.hdfs.server.namenode
Class FSDirectory

java.lang.Object
  org.apache.hadoop.hdfs.server.namenode.FSDirectory

All Implemented Interfaces:

Closeable

public class FSDirectory
extends Object
implements Closeable

FSDirectory stores the filesystem directory state. It handles writing/loading values to disk, and logging changes as we go. It keeps the filename->blockset mapping always-current and logged to disk.

Field Summary

static byte[]	DOT_INODES
static String	DOT_INODES_STRING
static byte[]	DOT_RESERVED
static String	DOT_RESERVED_PATH_PREFIX
static String	DOT_RESERVED_STRING

Method Summary

void	addToInodeMap(org.apache.hadoop.hdfs.server.namenode.INode inode) This method is always called with writeLock of FSDirectory held.
void	close() Shutdown the filestore
org.apache.hadoop.hdfs.server.namenode.INode	getInode(long id) Get the inode from inodeMap based on its inode id.
org.apache.hadoop.hdfs.server.namenode.INode	getINode(String src) Get INode associated with the file / directory.
org.apache.hadoop.hdfs.server.namenode.INode	getINode4Write(String src) Get INode associated with the file / directory.
INodeMap	getINodeMap()
INodesInPath	getINodesInPath4Write(String src) Get INode associated with the file / directory.
INodesInPath	getLastINodeInPath(String src) Get INode associated with the file / directory.
int	getReadHoldCount()
INodeDirectory	getRoot()
int	getWriteHoldCount()
long	getYieldCount()
static boolean	isReservedName(org.apache.hadoop.hdfs.server.namenode.INode inode) Check if a given inode name is reserved
static boolean	isReservedName(String src) Check if a given path is reserved
void	removeFromInodeMap(List<? extends org.apache.hadoop.hdfs.server.namenode.INode> inodes) This method is always called with writeLock of FSDirectory held.
protected void	setReady(boolean flag)

Methods inherited from class java.lang.Object

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

Field Detail

DOT_RESERVED_STRING

public static final String DOT_RESERVED_STRING

See Also:

Constant Field Values

DOT_RESERVED_PATH_PREFIX

public static final String DOT_RESERVED_PATH_PREFIX

See Also:

Constant Field Values

DOT_RESERVED

public static final byte[] DOT_RESERVED

DOT_INODES_STRING

public static final String DOT_INODES_STRING

See Also:

Constant Field Values

DOT_INODES

public static final byte[] DOT_INODES

Method Detail

getReadHoldCount

public int getReadHoldCount()

getWriteHoldCount

public int getWriteHoldCount()

getRoot

public INodeDirectory getRoot()

Returns:

the root directory inode.

setReady

protected void setReady(boolean flag)

close

public void close()
           throws IOException

Shutdown the filestore

Specified by:

close in interface Closeable

Throws:

IOException

getINode

public org.apache.hadoop.hdfs.server.namenode.INode getINode(String src)
                                                      throws org.apache.hadoop.fs.UnresolvedLinkException

Get INode associated with the file / directory.

Throws:

org.apache.hadoop.fs.UnresolvedLinkException

getLastINodeInPath

public INodesInPath getLastINodeInPath(String src)
                                throws org.apache.hadoop.fs.UnresolvedLinkException

Get INode associated with the file / directory.

Throws:

org.apache.hadoop.fs.UnresolvedLinkException

getINodesInPath4Write

public INodesInPath getINodesInPath4Write(String src)
                                   throws org.apache.hadoop.fs.UnresolvedLinkException,
                                          SnapshotAccessControlException

Get INode associated with the file / directory.

Throws:

org.apache.hadoop.fs.UnresolvedLinkException

SnapshotAccessControlException

getINode4Write

public org.apache.hadoop.hdfs.server.namenode.INode getINode4Write(String src)
                                                            throws org.apache.hadoop.fs.UnresolvedLinkException,
                                                                   SnapshotAccessControlException

Get INode associated with the file / directory.

Throws:

SnapshotAccessControlException - if path is in RO snapshot

org.apache.hadoop.fs.UnresolvedLinkException

getYieldCount

public long getYieldCount()

getINodeMap

public INodeMap getINodeMap()

addToInodeMap

public final void addToInodeMap(org.apache.hadoop.hdfs.server.namenode.INode inode)

This method is always called with writeLock of FSDirectory held.

removeFromInodeMap

public final void removeFromInodeMap(List<? extends org.apache.hadoop.hdfs.server.namenode.INode> inodes)

This method is always called with writeLock of FSDirectory held.

getInode

public org.apache.hadoop.hdfs.server.namenode.INode getInode(long id)

Get the inode from inodeMap based on its inode id.

Parameters:

id - The given id

Returns:

The inode associated with the given id

isReservedName

public static boolean isReservedName(org.apache.hadoop.hdfs.server.namenode.INode inode)

Check if a given inode name is reserved

isReservedName

public static boolean isReservedName(String src)

Check if a given path is reserved