org.kairosdb.bigqueue.page

Interface IMappedPageFactory

All Known Implementing Classes:

MappedPageFactoryImpl

public interface IMappedPageFactory

Memory mapped page management ADT

Author:

bulldog

Method Summary

Modifier and Type	Method and Description
IMappedPage	acquirePage(long index) Acquire a mapped page with specific index from the factory
void	deleteAllPages() delete all mapped pages currently available in this factory, this call will remove all pages from the cache and delete all back files.
void	deletePage(long index) delete a mapped page with specific index in this factory, this call will remove the page from the cache if it is cached and delete back file.
void	deletePages(Set<Long> indexes) delete mapped pages with a set of specific indexes in this factory, this call will remove the pages from the cache if they ware cached and delete back files.
void	deletePagesBefore(long timestamp) Delete all pages with last modified timestamp before the specific timestamp.
void	deletePagesBeforePageIndex(long pageIndex) Delete all pages before the specific index
void	flush() Persist any changes in cached mapped pages
Set<String>	getBackPageFileSet() A set of back page file names
long	getBackPageFileSize() Total size of all page files
int	getCacheSize() For test, get current cache size
Set<Long>	getExistingBackFileIndexSet() For test, get a list of indexes of current existing back files.
long	getFirstPageIndexBefore(long timestamp) Get index of a page file with last modified timestamp closest to specific timestamp.
String	getPageDir() Current set page directory.
long	getPageFileLastModifiedTime(long index) Get last modified timestamp of page file index
Set<Long>	getPageIndexSetBefore(long timestamp) Get all indexes of pages with last modified timestamp before the specific timestamp.
int	getPageSize() Current set page size, when creating pages, the factory will only create pages with this size.
void	releaseCachedPages() remove all cached pages from the cache and close resources associated with the cached pages.
void	releasePage(long index) Return the mapped page to the factory, calling thread release the page to inform the factory that it has finished with the page, so the factory get a chance to recycle the page to save memory.

Method Detail

acquirePage

IMappedPage acquirePage(long index)
                 throws IOException

Acquire a mapped page with specific index from the factory

Parameters:

index - the index of the page

Returns:

a mapped page

Throws:

IOException - exception thrown if there was any IO error during the acquire operation

releasePage

void releasePage(long index)

Return the mapped page to the factory, calling thread release the page to inform the factory that it has finished with the page, so the factory get a chance to recycle the page to save memory.

Parameters:

index - the index of the page

getPageSize

int getPageSize()

Current set page size, when creating pages, the factory will only create pages with this size.

Returns:

an integer number

getPageDir

String getPageDir()

Current set page directory.

Returns:

directory name

deletePage

void deletePage(long index)
         throws IOException

delete a mapped page with specific index in this factory, this call will remove the page from the cache if it is cached and delete back file.

Parameters:

index - the index of the page

Throws:

IOException - exception thrown if there was any IO error during the delete operation.

deletePages

void deletePages(Set<Long> indexes)
          throws IOException

delete mapped pages with a set of specific indexes in this factory, this call will remove the pages from the cache if they ware cached and delete back files.

Parameters:

indexes - the indexes of the pages

Throws:

IOException - exception thrown if IO error occurs

deleteAllPages

void deleteAllPages()
             throws IOException

delete all mapped pages currently available in this factory, this call will remove all pages from the cache and delete all back files.

Throws:

IOException - exception thrown if there was any IO error during the delete operation.

releaseCachedPages

void releaseCachedPages()
                 throws IOException

remove all cached pages from the cache and close resources associated with the cached pages.

Throws:

IOException - exception thrown if there was any IO error during the release operation.

getPageIndexSetBefore

Set<Long> getPageIndexSetBefore(long timestamp)

Get all indexes of pages with last modified timestamp before the specific timestamp.

Parameters:

timestamp - the timestamp to check

Returns:

a set of indexes

deletePagesBefore

void deletePagesBefore(long timestamp)
                throws IOException

Delete all pages with last modified timestamp before the specific timestamp.

Parameters:

timestamp - the timestamp to check

Throws:

IOException - exception thrown if there was any IO error during the delete operation.

deletePagesBeforePageIndex

void deletePagesBeforePageIndex(long pageIndex)
                         throws IOException

Delete all pages before the specific index

Parameters:

pageIndex - page file index to check

Throws:

IOException - exception thrown if there was any IO error during the delete operation.

getPageFileLastModifiedTime

long getPageFileLastModifiedTime(long index)

Get last modified timestamp of page file index

Parameters:

index - page index

Returns:

last modified time

getFirstPageIndexBefore

long getFirstPageIndexBefore(long timestamp)

Get index of a page file with last modified timestamp closest to specific timestamp.

Parameters:

timestamp - the timestamp to check

Returns:

a page index

getExistingBackFileIndexSet

Set<Long> getExistingBackFileIndexSet()

For test, get a list of indexes of current existing back files.

Returns:

a set of indexes

getCacheSize

int getCacheSize()

For test, get current cache size

Returns:

an integer number

flush

void flush()

Persist any changes in cached mapped pages

getBackPageFileSet

Set<String> getBackPageFileSet()

A set of back page file names

Returns:

file name set

getBackPageFileSize

long getBackPageFileSize()

Total size of all page files

Returns:

total size