Package org.kairosdb.bigqueue.page

Class MappedPageFactoryImpl

java.lang.Object

org.kairosdb.bigqueue.page.MappedPageFactoryImpl

All Implemented Interfaces:

IMappedPageFactory

public class MappedPageFactoryImpl
extends Object
implements IMappedPageFactory

Mapped mapped page resource manager, responsible for the creation, cache, recycle of the mapped pages. automatic paging and swapping algorithm is leveraged to ensure fast page fetch while keep memory usage efficient at the same time.

Author:

bulldog

Field Summary

Fields

Modifier and Type	Field	Description
static String	PAGE_FILE_NAME
static String	PAGE_FILE_SUFFIX

Constructor Summary

Constructors

Constructor	Description
MappedPageFactoryImpl(int pageSize, String pageDir, long cacheTTL)
MappedPageFactoryImpl(int pageSize, String pageDir, long cacheTTL, Clock clock, FileFactory fileFactory)

Method Summary

Modifier and Type	Method	Description
IMappedPage	acquirePage(long index)	Acquire a mapped page with specific index from the factory
void	deleteAllPages()	thread unsafe, caller need synchronization
void	deletePage(long index)	thread unsafe, caller need synchronization
void	deletePages(Set<Long> indexes)	thread unsafe, caller need synchronization
void	deletePagesBefore(long timestamp)	thread unsafe, caller need synchronization
void	deletePagesBeforePageIndex(long pageIndex)	Delete all pages before the specific index
void	flush()	thread unsafe, caller need synchronization
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()	thread unsafe, caller need synchronization
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.

Methods inherited from class java.lang.Object

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

Field Detail

PAGE_FILE_NAME

public static final String PAGE_FILE_NAME

See Also:

Constant Field Values

PAGE_FILE_SUFFIX

public static final String PAGE_FILE_SUFFIX

See Also:

Constant Field Values

Constructor Detail

MappedPageFactoryImpl

public MappedPageFactoryImpl(int pageSize,
                             String pageDir,
                             long cacheTTL,
                             Clock clock,
                             FileFactory fileFactory)

MappedPageFactoryImpl

public MappedPageFactoryImpl(int pageSize,
                             String pageDir,
                             long cacheTTL)

Method Detail

acquirePage

public IMappedPage acquirePage(long index)
                        throws IOException

Description copied from interface: IMappedPageFactory

Acquire a mapped page with specific index from the factory

Specified by:

acquirePage in interface IMappedPageFactory

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

getPageSize

public int getPageSize()

Description copied from interface: IMappedPageFactory

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

Specified by:

getPageSize in interface IMappedPageFactory

Returns:

an integer number

getPageDir

public String getPageDir()

Description copied from interface: IMappedPageFactory

Current set page directory.

Specified by:

getPageDir in interface IMappedPageFactory

Returns:

directory name

releasePage

public void releasePage(long index)

Description copied from interface: IMappedPageFactory

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.

Specified by:

releasePage in interface IMappedPageFactory

Parameters:

index - the index of the page

releaseCachedPages

public void releaseCachedPages()
                        throws IOException

thread unsafe, caller need synchronization

Specified by:

releaseCachedPages in interface IMappedPageFactory

Throws:

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

deleteAllPages

public void deleteAllPages()
                    throws IOException

thread unsafe, caller need synchronization

Specified by:

deleteAllPages in interface IMappedPageFactory

Throws:

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

deletePages

public void deletePages(Set<Long> indexes)
                 throws IOException

thread unsafe, caller need synchronization

Specified by:

deletePages in interface IMappedPageFactory

Parameters:

indexes - the indexes of the pages

Throws:

IOException - exception thrown if IO error occurs

deletePage

public void deletePage(long index)
                throws IOException

thread unsafe, caller need synchronization

Specified by:

deletePage in interface IMappedPageFactory

Parameters:

index - the index of the page

Throws:

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

getPageIndexSetBefore

public Set<Long> getPageIndexSetBefore(long timestamp)

Description copied from interface: IMappedPageFactory

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

Specified by:

getPageIndexSetBefore in interface IMappedPageFactory

Parameters:

timestamp - the timestamp to check

Returns:

a set of indexes

deletePagesBefore

public void deletePagesBefore(long timestamp)
                       throws IOException

thread unsafe, caller need synchronization

Specified by:

deletePagesBefore in interface IMappedPageFactory

Parameters:

timestamp - the timestamp to check

Throws:

IOException - exception thrown if IO error occurs

deletePagesBeforePageIndex

public void deletePagesBeforePageIndex(long pageIndex)
                                throws IOException

Description copied from interface: IMappedPageFactory

Delete all pages before the specific index

Specified by:

deletePagesBeforePageIndex in interface IMappedPageFactory

Parameters:

pageIndex - page file index to check

Throws:

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

getExistingBackFileIndexSet

public Set<Long> getExistingBackFileIndexSet()

Description copied from interface: IMappedPageFactory

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

Specified by:

getExistingBackFileIndexSet in interface IMappedPageFactory

Returns:

a set of indexes

getCacheSize

public int getCacheSize()

Description copied from interface: IMappedPageFactory

For test, get current cache size

Specified by:

getCacheSize in interface IMappedPageFactory

Returns:

an integer number

getPageFileLastModifiedTime

public long getPageFileLastModifiedTime(long index)

Description copied from interface: IMappedPageFactory

Get last modified timestamp of page file index

Specified by:

getPageFileLastModifiedTime in interface IMappedPageFactory

Parameters:

index - page index

Returns:

last modified time

getFirstPageIndexBefore

public long getFirstPageIndexBefore(long timestamp)

Description copied from interface: IMappedPageFactory

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

Specified by:

getFirstPageIndexBefore in interface IMappedPageFactory

Parameters:

timestamp - the timestamp to check

Returns:

a page index

flush

public void flush()

thread unsafe, caller need synchronization

Specified by:

flush in interface IMappedPageFactory

getBackPageFileSet

public Set<String> getBackPageFileSet()

Description copied from interface: IMappedPageFactory

A set of back page file names

Specified by:

getBackPageFileSet in interface IMappedPageFactory

Returns:

file name set

getBackPageFileSize

public long getBackPageFileSize()

Description copied from interface: IMappedPageFactory

Total size of all page files

Specified by:

getBackPageFileSize in interface IMappedPageFactory

Returns:

total size