Package db

Interface RecordNode

public interface RecordNode

Table record leaf nodes within the BTree structure.

Method Summary

Modifier and Type	Method	Description
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.
int	getKeyOffset(int index)	Get the key offset within the node's data buffer
InteriorNode	getParent()
int	getRecordOffset(int index)	Get the record offset within the node's data buffer
boolean	isConsistent(java.lang.String tableName, TaskMonitor monitor)	Check the consistency of this node and all of its children.
void	setKeyCount(int cnt)	Set the number of keys contained within this node.

Method Detail

getRecordOffset

int getRecordOffset(int index)
             throws java.io.IOException

Get the record offset within the node's data buffer

Parameters:

index - key/record index

Returns:

positive record offset within buffer, or a negative bufferID for indirect record storage in a dedicated buffer

Throws:

java.io.IOException - if IO error occurs

getKeyOffset

int getKeyOffset(int index)
          throws java.io.IOException

Get the key offset within the node's data buffer

Parameters:

index - key/record index

Returns:

positive record offset within buffer

Throws:

java.io.IOException - if IO error occurs

getParent

InteriorNode getParent()

Returns:

the parent node or null if this is the root

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