Package com.semedy.reasoner.edb.persistentstore.bplustree

Class BPlusLeafRecords<KeyType,KeyBufferType>

java.lang.Object

com.semedy.reasoner.edb.persistentstore.bplustree.BPlusNode<KeyType,KeyBufferType>

com.semedy.reasoner.edb.persistentstore.bplustree.BPlusLeaf<KeyType,KeyBufferType>

com.semedy.reasoner.edb.persistentstore.bplustree.BPlusLeafRecords<KeyType,KeyBufferType>

All Implemented Interfaces:

CacheUnit

Direct Known Subclasses:

BPlusLeafIndex

public class BPlusLeafRecords<KeyType,KeyBufferType>
extends BPlusLeaf<KeyType,KeyBufferType>

A leaf is the node in a B+ tree containing records. Although we want them to be generic,
most B+ trees are specialized. As a result, the only thing generic about the tree is the key

Author:

angele

Nested Class Summary

Nested classes/interfaces inherited from class com.semedy.reasoner.edb.persistentstore.bplustree.BPlusNode

BPlusNode.BPlusStatus

Constructor Summary

Constructors

Constructor	Description
BPlusLeafRecords(BPlusKeys<KeyType,KeyBufferType> keys, int maxSizeInBytes, BPlusTree<KeyType,KeyBufferType> bplustree)
BPlusLeafRecords(BPlusKeys<KeyType,KeyBufferType> keys, long[] records, int maxSizeInBytes, BPlusTree<KeyType,KeyBufferType> bplustree)	Initializes leaf.

Method Summary

Modifier and Type	Method	Description
boolean	append(KeyType key, long record)	append a key with a record
long	borrowFirstRecord()	Borrow the first record
long	borrowRecord()	borrows the rightmost record
byte[]	createBytes()	Map node to an array of bytes
static BPlusLeafRecords<long[],TupleBuffer>	createLeaf(byte[] bytes, KeysFactory<long[],TupleBuffer> keysFactory, BPlusTree<long[],TupleBuffer> bplustree)	Method for creating a leaf from the given byte array.
boolean	delete(KeyType keyToDelete)	Deletes the key (and the associated record offset) from this node.
void	destroy()	free up ressources at the end (CacheManager.clear)
void	doneBorrowing()	performs several cleaning up actions after borrowing from the right.
void	doneBorrowingFirst()	performs several cleanign up actions after borrowing from the left.
Object	getIndexBuffer(int index)	get attached object at index
long	getObjectSize(int index)	get size of attached object at index
long	getRecord(int index)	get record at index
long[]	getRecords()
boolean	insert(KeyType key, long record)	Inserts a key and the record offset into the node.
boolean	isLeaf()	A quick checker to see if the node is a leaf- if so, we have found the final result of the search.
void	remove()
long	search(KeyType key)	Searches for the given value.
long	searchBuffer(KeyBufferType key)
int	searchIndex(KeyType key)	Searches for index of the key Returns -1 it key is not contained
int	searchIndexBuffer(KeyBufferType key)	Searches for hte (possible) index of the key
boolean	set(KeyType key, long record)	Sets the record of a given key returns false if key is not there
void	substitute(BPlusKeys<KeyType,KeyBufferType> key, long[] record, long leftOffs)

Methods inherited from class com.semedy.reasoner.edb.persistentstore.bplustree.BPlusLeaf

checkSanity, replace, searchIndexToInsert, searchIndexToInsertByBuffer

Methods inherited from class com.semedy.reasoner.edb.persistentstore.bplustree.BPlusNode

borrowFirstKey, borrowKey, canBeBorrowedFrom, clear, detach, getFather, getIndexInFather, getKeys, getLast, getNext, getNumKeys, getOffset, getStatus, isEmpty, isFull, isReleasable, release, setFather, setLast, setNext, setStatus, sizeInBytes, toString, touch, underflow

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

BPlusLeafRecords

public BPlusLeafRecords(BPlusKeys<KeyType,KeyBufferType> keys,
 int maxSizeInBytes,
 BPlusTree<KeyType,KeyBufferType> bplustree)

Parameters:

keys -

maxSizeInBytes -

bplustree -

BPlusLeafRecords

public BPlusLeafRecords(BPlusKeys<KeyType,KeyBufferType> keys,
 long[] records,
 int maxSizeInBytes,
 BPlusTree<KeyType,KeyBufferType> bplustree)

Initializes leaf.

Parameters:

keys -

records -

maxSizeInBytes -

bplustree -

Method Details

substitute

public void substitute(BPlusKeys<KeyType,KeyBufferType> key,
 long[] record,
 long leftOffs)

Overrides:

substitute in class BPlusLeaf<KeyType,KeyBufferType>

delete

public boolean delete(KeyType keyToDelete)

Deletes the key (and the associated record offset) from this node. First, we find the index of the key. Make a temp array containing keys[0, indexToSkip - 1] copy keys[indexToSkip + 1, keys.length - 1] over. Do the same with the records.

Overrides:

delete in class BPlusLeaf<KeyType,KeyBufferType>

Parameters:

keyToDelete -

insert

public boolean insert(KeyType key,
 long record)
               throws IOException

Inserts a key and the record offset into the node. First, we find the index where these items need to be. Then copy all elements up to that point into a temp array. Shove the new key in, copy the rest of the elements. use the same index and do the same with the records.

Overrides:

insert in class BPlusLeaf<KeyType,KeyBufferType>

Parameters:

key -

record -

Throws:

IOException

set

public boolean set(KeyType key,
 long record)

Sets the record of a given key
returns false if key is not there

Overrides:

set in class BPlusLeaf<KeyType,KeyBufferType>

Parameters:

key -

record -

append

public boolean append(KeyType key,
 long record)
               throws IOException

Description copied from class: BPlusLeaf

append a key with a record

Overrides:

append in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

Throws:

IOException

isLeaf

public boolean isLeaf()

Description copied from class: BPlusNode

A quick checker to see if the node is a leaf- if so, we have found the final result of the search.

Overrides:

isLeaf in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

true if this is a leaf

search

public long search(KeyType key)

Searches for the given value.

Overrides:

search in class BPlusLeaf<KeyType,KeyBufferType>

Parameters:

key -

Returns:

the value for the key, or -1 if not found.

searchIndex

public int searchIndex(KeyType key)

Description copied from class: BPlusLeaf

Searches for index of the key Returns -1 it key is not contained

Overrides:

searchIndex in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

searchIndexBuffer

public int searchIndexBuffer(KeyBufferType key)

Description copied from class: BPlusLeaf

Searches for hte (possible) index of the key

Overrides:

searchIndexBuffer in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

searchBuffer

public long searchBuffer(KeyBufferType key)

Overrides:

searchBuffer in class BPlusLeaf<KeyType,KeyBufferType>

getRecords

public long[] getRecords()

Overrides:

getRecords in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

array of records

getRecord

public long getRecord(int index)

get record at index

Overrides:

getRecord in class BPlusLeaf<KeyType,KeyBufferType>

Parameters:

index -

Returns:

getIndexBuffer

public Object getIndexBuffer(int index)
                      throws IOException

get attached object at index

Overrides:

getIndexBuffer in class BPlusLeaf<KeyType,KeyBufferType>

Throws:

IOException

getObjectSize

public long getObjectSize(int index)
                   throws IOException

get size of attached object at index

Overrides:

getObjectSize in class BPlusLeaf<KeyType,KeyBufferType>

Throws:

IOException

borrowRecord

public long borrowRecord()

borrows the rightmost record

Overrides:

borrowRecord in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

the rightmost record

doneBorrowing

public void doneBorrowing()

Description copied from class: BPlusNode

performs several cleaning up actions after borrowing from the right.

Overrides:

doneBorrowing in class BPlusLeaf<KeyType,KeyBufferType>

doneBorrowingFirst

public void doneBorrowingFirst()

Description copied from class: BPlusNode

performs several cleanign up actions after borrowing from the left.

Overrides:

doneBorrowingFirst in class BPlusLeaf<KeyType,KeyBufferType>

borrowFirstRecord

public long borrowFirstRecord()

Borrow the first record

Overrides:

borrowFirstRecord in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

the first record

remove

public void remove()

Overrides:

remove in class BPlusLeaf<KeyType,KeyBufferType>

destroy

public void destroy()

Description copied from interface: CacheUnit

free up ressources at the end (CacheManager.clear)

Specified by:

destroy in interface CacheUnit

Overrides:

destroy in class BPlusLeaf<KeyType,KeyBufferType>

createBytes

public byte[] createBytes()

Map node to an array of bytes

Overrides:

createBytes in class BPlusLeaf<KeyType,KeyBufferType>

Returns:

createLeaf

public static BPlusLeafRecords<long[],TupleBuffer> createLeaf(byte[] bytes,
 KeysFactory<long[],TupleBuffer> keysFactory,
 BPlusTree<long[],TupleBuffer> bplustree)

Method for creating a leaf from the given byte array.

Parameters:

bytes -

Returns: