Package org.h2.mvstore

Class Page.Leaf<K,V>

java.lang.Object

org.h2.mvstore.Page<K,V>

org.h2.mvstore.Page.Leaf<K,V>

All Implemented Interfaces:

java.lang.Cloneable

Enclosing class:

Page<K,V>

private static class Page.Leaf<K,V>
extends Page<K,V>

Nested Class Summary

Nested classes/interfaces inherited from class org.h2.mvstore.Page

Page.PageReference<K,V>

Field Summary

Fields

Modifier and Type	Field	Description
private V[]	values	The storage for values.

Fields inherited from class org.h2.mvstore.Page

map, PAGE_LEAF_MEMORY, PAGE_MEMORY_CHILD, PAGE_NODE_MEMORY, pageNo

Constructor Summary

Constructors

Modifier	Constructor	Description
(package private)	Leaf(MVMap<K,V> map)
(package private)	Leaf(MVMap<K,V> map, K[] keys, V[] values)
private	Leaf(MVMap<K,V> map, Page.Leaf<K,V> source)

Method Summary

Modifier and Type	Method	Description
protected int	calculateMemory()	Calculate estimated memory used in persistent case.
Page<K,V>	copy(MVMap<K,V> map, boolean eraseChildrenRefs)	Create a copy of this page with potentially different owning map.
void	dump(java.lang.StringBuilder buff)	Dump debug data for this page.
void	expand(int extraKeyCount, K[] extraKeys, V[] extraValues)	Append additional key/value mappings to this Page.
CursorPos<K,V>	getAppendCursorPos(CursorPos<K,V> cursorPos)	Extend path from a given CursorPos chain to "append point" in a B-tree, rooted at this Page.
Page<K,V>	getChildPage(int index)	Get the child page at the given index.
long	getChildPagePos(int index)	Get the position of the child.
(package private) long	getCounts(int index)	Get the number of key-value pairs for a given child.
int	getNodeType()
CursorPos<K,V>	getPrependCursorPos(CursorPos<K,V> cursorPos)	Extend path from a given CursorPos chain to "prepend point" in a B-tree, rooted at this Page.
int	getRawChildPageCount()
long	getTotalCount()	Get the total number of key-value pairs, including child pages.
V	getValue(int index)	Get the value at the given index.
void	insertLeaf(int index, K key, V value)	Insert a key-value pair into this leaf.
void	insertNode(int index, K key, Page<K,V> childPage)	Insert a child page into this node.
protected void	readPayLoad(java.nio.ByteBuffer buff)	Read the page payload from the buffer.
(package private) void	releaseSavedPages()	Unlink the children recursively after all data is written.
void	remove(int index)	Remove the key and value (or child) at the given index.
int	removeAllRecursive(long version)	Remove all page data recursively.
void	setChild(int index, Page<K,V> c)	Replace the child page.
V	setValue(int index, V value)	Replace the value at an index in this page.
private V	setValueInternal(int index, V value)
Page<K,V>	split(int at)	Split the page.
protected void	writeChildren(WriteBuffer buff, boolean withCounts)	Write page children to the buff.
(package private) void	writeUnsavedRecursive(Chunk chunk, WriteBuffer buff, java.util.List<java.lang.Long> toc)	Store this page and all children that are changed, in reverse order, and update the position and the children.
protected void	writeValues(WriteBuffer buff)	Write values that the buffer contains to the buff.

Methods inherited from class org.h2.mvstore.Page

addMemory, binarySearch, clone, copy, createEmptyLeaf, createEmptyNode, createKeyStorage, createLeaf, createNode, createRefStorage, createValueStorage, expandKeys, get, getDiskSpaceUsed, getKey, getKeyCount, getMapId, getMemory, getPos, insertKey, isComplete, isLeaf, isPersistent, isRemoved, isSaved, read, recalculateMemory, removePage, setComplete, setKey, splitKeys, toString, write

Methods inherited from class java.lang.Object

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

Field Detail

values

private V[] values

The storage for values.

Constructor Detail

Leaf

Leaf(MVMap<K,V> map)

Leaf

private Leaf(MVMap<K,V> map,
             Page.Leaf<K,V> source)

Leaf

Leaf(MVMap<K,V> map,
     K[] keys,
     V[] values)

Method Detail

getNodeType

public int getNodeType()

Specified by:

getNodeType in class Page<K,V>

copy

public Page<K,V> copy(MVMap<K,V> map,
                            boolean eraseChildrenRefs)

Description copied from class: Page

Create a copy of this page with potentially different owning map. This is used exclusively during bulk map copying. Child page references for nodes are cleared (re-pointed to an empty page) to be filled-in later to copying procedure. This way it can be saved mid-process without tree integrity violation

Specified by:

copy in class Page<K,V>

Parameters:

map - new map to own resulting page

eraseChildrenRefs - whether cloned Page should have no child references or keep originals

Returns:

the page

getChildPage

public Page<K,V> getChildPage(int index)

Description copied from class: Page

Get the child page at the given index.

Specified by:

getChildPage in class Page<K,V>

Parameters:

index - the index

Returns:

the child page

getChildPagePos

public long getChildPagePos(int index)

Description copied from class: Page

Get the position of the child.

Specified by:

getChildPagePos in class Page<K,V>

Parameters:

index - the index

Returns:

the position

getValue

public V getValue(int index)

Description copied from class: Page

Get the value at the given index.

Specified by:

getValue in class Page<K,V>

Parameters:

index - the index

Returns:

the value

split

public Page<K,V> split(int at)

Description copied from class: Page

Split the page. This modifies the current page.

Specified by:

split in class Page<K,V>

Parameters:

at - the split index

Returns:

the page with the entries after the split index

expand

public void expand(int extraKeyCount,
                   K[] extraKeys,
                   V[] extraValues)

Description copied from class: Page

Append additional key/value mappings to this Page. New mappings suppose to be in correct key order.

Specified by:

expand in class Page<K,V>

Parameters:

extraKeyCount - number of mappings to be added

extraKeys - to be added

extraValues - to be added

getTotalCount

public long getTotalCount()

Description copied from class: Page

Get the total number of key-value pairs, including child pages.

Specified by:

getTotalCount in class Page<K,V>

Returns:

the number of key-value pairs

getCounts

long getCounts(int index)

Description copied from class: Page

Get the number of key-value pairs for a given child.

Specified by:

getCounts in class Page<K,V>

Parameters:

index - the child index

Returns:

the descendant count

setChild

public void setChild(int index,
                     Page<K,V> c)

Description copied from class: Page

Replace the child page.

Specified by:

setChild in class Page<K,V>

Parameters:

index - the index

c - the new child page

setValue

public V setValue(int index,
                  V value)

Description copied from class: Page

Replace the value at an index in this page.

Specified by:

setValue in class Page<K,V>

Parameters:

index - the index

value - the new value

Returns:

the old value

setValueInternal

private V setValueInternal(int index,
                           V value)

insertLeaf

public void insertLeaf(int index,
                       K key,
                       V value)

Description copied from class: Page

Insert a key-value pair into this leaf.

Specified by:

insertLeaf in class Page<K,V>

Parameters:

index - the index

key - the key

value - the value

insertNode

public void insertNode(int index,
                       K key,
                       Page<K,V> childPage)

Description copied from class: Page

Insert a child page into this node.

Specified by:

insertNode in class Page<K,V>

Parameters:

index - the index

key - the key

childPage - the child page

remove

public void remove(int index)

Description copied from class: Page

Remove the key and value (or child) at the given index.

Overrides:

remove in class Page<K,V>

Parameters:

index - the index

removeAllRecursive

public int removeAllRecursive(long version)

Description copied from class: Page

Remove all page data recursively.

Specified by:

removeAllRecursive in class Page<K,V>

Parameters:

version - at which page got removed

Returns:

adjustment for "unsaved memory" amount

getPrependCursorPos

public CursorPos<K,V> getPrependCursorPos(CursorPos<K,V> cursorPos)

Description copied from class: Page

Extend path from a given CursorPos chain to "prepend point" in a B-tree, rooted at this Page.

Specified by:

getPrependCursorPos in class Page<K,V>

Parameters:

cursorPos - presumably pointing to this Page (null if real root), to build upon

Returns:

new head of the CursorPos chain

getAppendCursorPos

public CursorPos<K,V> getAppendCursorPos(CursorPos<K,V> cursorPos)

Description copied from class: Page

Extend path from a given CursorPos chain to "append point" in a B-tree, rooted at this Page.

Specified by:

getAppendCursorPos in class Page<K,V>

Parameters:

cursorPos - presumably pointing to this Page (null if real root), to build upon

Returns:

new head of the CursorPos chain

readPayLoad

protected void readPayLoad(java.nio.ByteBuffer buff)

Description copied from class: Page

Read the page payload from the buffer.

Specified by:

readPayLoad in class Page<K,V>

Parameters:

buff - the buffer

writeValues

protected void writeValues(WriteBuffer buff)

Description copied from class: Page

Write values that the buffer contains to the buff.

Specified by:

writeValues in class Page<K,V>

Parameters:

buff - the target buffer

writeChildren

protected void writeChildren(WriteBuffer buff,
                             boolean withCounts)

Description copied from class: Page

Write page children to the buff.

Specified by:

writeChildren in class Page<K,V>

Parameters:

buff - the target buffer

withCounts - true if the descendant counts should be written

writeUnsavedRecursive

void writeUnsavedRecursive(Chunk chunk,
                           WriteBuffer buff,
                           java.util.List<java.lang.Long> toc)

Description copied from class: Page

Store this page and all children that are changed, in reverse order, and update the position and the children.

Specified by:

writeUnsavedRecursive in class Page<K,V>

Parameters:

chunk - the chunk

buff - the target buffer

toc - prospective table of content

releaseSavedPages

void releaseSavedPages()

Description copied from class: Page

Unlink the children recursively after all data is written.

Specified by:

releaseSavedPages in class Page<K,V>

getRawChildPageCount

public int getRawChildPageCount()

Specified by:

getRawChildPageCount in class Page<K,V>

calculateMemory

protected int calculateMemory()

Description copied from class: Page

Calculate estimated memory used in persistent case.

Overrides:

calculateMemory in class Page<K,V>

Returns:

memory in bytes

dump

public void dump(java.lang.StringBuilder buff)

Description copied from class: Page

Dump debug data for this page.

Overrides:

dump in class Page<K,V>

Parameters:

buff - append buffer