org.terracotta.offheapstore.disk.paging
Class MappedPageSource

java.lang.Object
  org.terracotta.offheapstore.disk.paging.MappedPageSource

All Implemented Interfaces:

PageSource

public class MappedPageSource
extends Object
implements PageSource

Author:

Chris Dennis

Constructor Summary

MappedPageSource(File file)

MappedPageSource(File file, boolean truncate)

MappedPageSource(File file, boolean truncate, long size)

MappedPageSource(File file, long size)

Method Summary

MappedPage	allocate(int size, boolean thief, boolean victim, OffHeapStorageArea owner) Attempt to allocate a page of the given size.
Long	allocateRegion(long size)
MappedPage	claimPage(long address, long size)
long	claimRegion(long address, long size)
void	close()
void	flush()
void	free(Page page)
void	freeRegion(long address)
long	getAddress(Page underlying)
File	getFile()
FileChannel	getReadableChannel()
FileChannel	getWritableChannel()

Methods inherited from class java.lang.Object

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

Constructor Detail

MappedPageSource

public MappedPageSource(File file)
                 throws IOException

Throws:

IOException

MappedPageSource

public MappedPageSource(File file,
                        long size)
                 throws IOException

Throws:

IOException

MappedPageSource

public MappedPageSource(File file,
                        boolean truncate)
                 throws IOException

Throws:

IOException

MappedPageSource

public MappedPageSource(File file,
                        boolean truncate,
                        long size)
                 throws IOException

Throws:

IOException

Method Detail

allocateRegion

public Long allocateRegion(long size)

freeRegion

public void freeRegion(long address)

claimRegion

public long claimRegion(long address,
                        long size)
                 throws IOException

Throws:

IOException

getReadableChannel

public FileChannel getReadableChannel()

getWritableChannel

public FileChannel getWritableChannel()

getFile

public File getFile()

allocate

public MappedPage allocate(int size,
                           boolean thief,
                           boolean victim,
                           OffHeapStorageArea owner)

Description copied from interface: PageSource

Attempt to allocate a page of the given size.

Allocations identified as thieves will if necessary 'steal' space from previous allocations identified as 'victims' in order to fulfill the allocation request. owner is the area from which the returned page can subsequently be stolen or recovered. This is most likely to be the calling instance.

Specified by:

allocate in interface PageSource

Parameters:

size - size of page to allocate

thief - true if the allocation can steal space from victims

victim - true if the allocated page should be eligible for stealing

owner - owner from which subsequent steal should occur

Returns:

an allocated page, or null in the case of failure

free

public void free(Page page)

Specified by:

free in interface PageSource

claimPage

public MappedPage claimPage(long address,
                            long size)
                     throws IOException

Throws:

IOException

getAddress

public long getAddress(Page underlying)

flush

public void flush()
           throws IOException

Throws:

IOException

close

public void close()
           throws IOException

Throws:

IOException