Package db

Interface FieldKeyInteriorNode

All Superinterfaces:

InteriorNode

public interface FieldKeyInteriorNode
extends InteriorNode

FieldKeyInteriorNode defines a common interface for FieldKeyNode implementations which are also an InteriorNode.

Method Summary

Modifier and Type	Method	Description
int	compareKeyField(Field k, int keyIndex)	Performs a fast in-place key comparison of the specified key value with a key stored within this node at the specified keyIndex.
void	delete()	Delete this node and all child nodes.
DataBuffer	getBuffer()
int	getBufferId()
int[]	getBufferReferences()	Return all buffer IDs for those buffers which are children of this buffer.
int	getKeyCount()
Field	getKeyField(int index)	Get the key value at a specific index.
int	getKeyIndex(Field key)	Perform a binary search to locate the specified key and derive an index into the Buffer ID storage.
db.FieldKeyRecordNode	getLeafNode(Field key)	Get the leaf node which contains the specified key.
db.FieldKeyRecordNode	getLeftmostLeafNode()	Get the left-most leaf node within the tree.
FieldKeyInteriorNode	getParent()
db.FieldKeyRecordNode	getRightmostLeafNode()	Get the right-most leaf node within the tree.
boolean	isConsistent(java.lang.String tableName, TaskMonitor monitor)	Check the consistency of this node and all of its children.
void	keyChanged(Field oldKey, Field newKey, db.FieldKeyNode childNode)	Callback method for when a child node's leftmost key changes.
void	setKeyCount(int cnt)	Set the number of keys contained within this node.

Method Detail

keyChanged

void keyChanged(Field oldKey,
                Field newKey,
                db.FieldKeyNode childNode)
         throws java.io.IOException

Callback method for when a child node's leftmost key changes.

Parameters:

oldKey - previous leftmost key.

newKey - new leftmost key.

childNode - child node containing oldKey (null if not a VarKeyNode)

Throws:

java.io.IOException - if IO error occurs

getBufferId

int getBufferId()

Returns:

the data buffer ID associated with this node.

getBuffer

DataBuffer getBuffer()

Returns:

the data buffer associated with this node.

getKeyCount

int getKeyCount()

Returns:

the number of keys contained within this node.

setKeyCount

void setKeyCount(int cnt)

Set the number of keys contained within this node.

Parameters:

cnt - key count

getKeyField

Field getKeyField(int index)
           throws java.io.IOException

Get the key value at a specific index.

Parameters:

index - key index

Returns:

key value

Throws:

java.io.IOException - thrown if an IO error occurs

getKeyIndex

int getKeyIndex(Field key)
         throws java.io.IOException

Perform a binary search to locate the specified key and derive an index into the Buffer ID storage. This method is intended to find the insertion index or exact match for a child key. A negative value will be returned when an exact match is not found and may be transformed into an insertion index (insetIndex = -returnedIndex-1).

Parameters:

key - key to search for

Returns:

int buffer ID index.

Throws:

java.io.IOException - thrown if an IO error occurs

delete

void delete()
     throws java.io.IOException

Delete this node and all child nodes.

Throws:

java.io.IOException - thrown if IO error occurs

getBufferReferences

int[] getBufferReferences()

Return all buffer IDs for those buffers which are children of this buffer.

Returns:

array of buffer IDs

isConsistent

boolean isConsistent(java.lang.String tableName,
                     TaskMonitor monitor)
              throws java.io.IOException,
                     CancelledException

Check the consistency of this node and all of its children.

Parameters:

tableName - name of table containing this node

monitor - task monitor

Returns:

true if consistency check passed, else false

Throws:

java.io.IOException - if IO error occured

CancelledException - if task cancelled

getParent

FieldKeyInteriorNode getParent()

Returns:

the parent node or null if this is the root

getLeafNode

db.FieldKeyRecordNode getLeafNode(Field key)
                           throws java.io.IOException

Get the leaf node which contains the specified key.

Parameters:

key - key value

Returns:

leaf node

Throws:

java.io.IOException - thrown if an IO error occurs

getLeftmostLeafNode

db.FieldKeyRecordNode getLeftmostLeafNode()
                                   throws java.io.IOException

Get the left-most leaf node within the tree.

Returns:

left-most leaf node.

Throws:

java.io.IOException - thrown if IO error occurs

getRightmostLeafNode

db.FieldKeyRecordNode getRightmostLeafNode()
                                    throws java.io.IOException

Get the right-most leaf node within the tree.

Returns:

right-most leaf node.

Throws:

java.io.IOException - thrown if IO error occurs

compareKeyField

int compareKeyField(Field k,
                    int keyIndex)

Performs a fast in-place key comparison of the specified key value with a key stored within this node at the specified keyIndex.

Parameters:

k - key value to be compared

keyIndex - key index to another key within this node's buffer

Returns:

comparison value, zero if equal, -1 if k has a value less than the store key, or +1 if k has a value greater than the stored key located at keyIndex.