rossi.fstools.fs.reiserfs
Class LeafNode

java.lang.Object
  rossi.fstools.fs.reiserfs.FBlock
      rossi.fstools.fs.reiserfs.LeafNode

All Implemented Interfaces:

DiskStructure

public class LeafNode

extends FBlock

Representation of an leaf node of the B+Tree.

This structure is the container for Items in the filesystem.

Following the block header (at offset 0x18), is an array of N ItemHeaders, followed by some free space. The from the end of the block working backwards is an array of items. The item headers need to be read first to determine where the item bodies are.

Field Summary

protected ItemHead[]

itemHeaders

Fields inherited from class rossi.fstools.fs.reiserfs.FBlock

blocknum, freeSpace, level, numItems, parent, reserved, rightKey, sb

Constructor Summary

LeafNode(ReiserSuperBlock sb, int blocknum)
Create a new leaf node

Method Summary

Item	getItem(byte[] buffer, int offset, ItemHead ih) Gets an item from this block given the item header.
Item	getItem(byte[] buffer, int offset, Key key) Returns the item matching the given key, or the next one greater.
ItemHead[]	getItemHeaders() Get an array of all the ItemHeaders in this leaf.
void	loadFromBuffer(byte[] buffer, int blkoffset) Load this structure from disk.
void	setItemHeaders(ItemHead[] aItemHeaders)

Methods inherited from class rossi.fstools.fs.reiserfs.FBlock

createFromBuffer, getBlockHeaderSize, getBlockNum, getDataSize, getFreeSpace, getLevel, getNumItems, getParent, getReserved, getRightKey, getSuperBlock, setFreeSpace, setLevel, setNumItems, setParent, setReserved, setRightKey

Methods inherited from class java.lang.Object

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

Field Detail

itemHeaders

protected ItemHead[] itemHeaders

Constructor Detail

LeafNode

public LeafNode(ReiserSuperBlock sb,
                int blocknum)

Create a new leaf node

Parameters:

sb - a ReiserSuperBlock for this filesystem.

blocknum - number of this block

Method Detail

getItemHeaders

public ItemHead[] getItemHeaders()

Get an array of all the ItemHeaders in this leaf.

Returns:

ItemHead[]

setItemHeaders

public void setItemHeaders(ItemHead[] aItemHeaders)

getItem

public Item getItem(byte[] buffer,
                    int offset,
                    Key key)
             throws FsException

Returns the item matching the given key, or the next one greater.

Returns:

the requested Item

Throws:

FsException

getItem

public Item getItem(byte[] buffer,
                    int offset,
                    ItemHead ih)
             throws FsException

Gets an item from this block given the item header.

Parameters:

buffer - contains this block at offset.

offset - points to the start of this block.

Returns:

the requested item

Throws:

FsException

loadFromBuffer

public void loadFromBuffer(byte[] buffer,
                           int blkoffset)
                    throws FsException

Description copied from class: FBlock

Load this structure from disk.

Specified by:

loadFromBuffer in interface DiskStructure

Overrides:

loadFromBuffer in class FBlock

Throws:

FsException - if a parse error occurs

See Also:

DiskStructure.loadFromBuffer(byte[], int)