de.lmu.ifi.dbs.elki.persistent

Interface PageFile<P extends Page>

Type Parameters:

P - Page file

All Known Implementing Classes:

AbstractPageFile, AbstractStoringPageFile, LRUCache, MemoryPageFile, OnDiskArrayPageFile, PersistentPageFile

public interface PageFile<P extends Page>

Page file interface.

Author:

Erich Schubert

Method Summary

Methods

Modifier and Type	Method and Description
void	clear() Clears this PageFile.
void	close() Closes this file.
void	deletePage(int pageID) Deletes the node with the specified id from this file.
int	getNextPageID() Returns the next page id.
int	getPageSize() Get the page size of this page file.
boolean	initialize(PageHeader header) Initialize the page file with the given header - return "true" if the file already existed.
void	logStatistics() Log some statistics to the appropriate logger.
P	readPage(int pageID) Reads the page with the given id from this file.
void	setNextPageID(int nextPageID) Sets the next page id.
int	setPageID(P page) Sets the id of the given page.
int	writePage(P page) Writes a page into this file.

Method Detail

setPageID

int setPageID(P page)

Sets the id of the given page.

Parameters:

page - the page to set the id

Returns:

the page id

writePage

int writePage(P page)

Writes a page into this file. The method tests if the page has already an id, otherwise a new id is assigned and returned.

Parameters:

page - the page to be written

Returns:

the id of the page

readPage

P readPage(int pageID)

Reads the page with the given id from this file.

Parameters:

pageID - the id of the page to be returned

Returns:

the page with the given pageId

deletePage

void deletePage(int pageID)

Deletes the node with the specified id from this file.

Parameters:

pageID - the id of the node to be deleted

close

void close()

Closes this file.

clear

void clear()

Clears this PageFile.

getNextPageID

int getNextPageID()

Returns the next page id.

Returns:

the next page id

setNextPageID

void setNextPageID(int nextPageID)

Sets the next page id.

Parameters:

nextPageID - the next page id to be set

getPageSize

int getPageSize()

Get the page size of this page file.

Returns:

page size

initialize

boolean initialize(PageHeader header)

Initialize the page file with the given header - return "true" if the file already existed.

Parameters:

header - Header

Returns:

true when the file already existed.

logStatistics

void logStatistics()

Log some statistics to the appropriate logger.