Package io.atomix.utils.memory

Class MappedMemory

java.lang.Object

io.atomix.utils.memory.MappedMemory

All Implemented Interfaces:

Memory

public class MappedMemory
extends Object
implements Memory

Mapped memory.

This is a special memory descriptor that handles management of MappedByteBuffer based memory. The mapped memory descriptor simply points to the memory address of the underlying byte buffer. When memory is reallocated, the parent MappedMemoryAllocator is used to create a new MappedByteBuffer and free the existing buffer.

Author:

Jordan Halterman

Nested Class Summary

Nested classes/interfaces inherited from interface io.atomix.utils.memory.Memory

Memory.Util

Constructor Summary

Constructors

Constructor	Description
MappedMemory(MappedByteBuffer buffer, MappedMemoryAllocator allocator)

Method Summary

Modifier and Type	Method	Description
static MappedMemory	allocate(File file, int size)	Allocates memory mapped to a file on disk.
static MappedMemory	allocate(File file, FileChannel.MapMode mode, int size)	Allocates memory mapped to a file on disk.
void	close()
void	flush()	Flushes the mapped buffer to disk.
void	free()	Frees the memory.
int	size()	Returns the memory count.

Methods inherited from class java.lang.Object

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

Constructor Detail

MappedMemory

public MappedMemory(MappedByteBuffer buffer,
                    MappedMemoryAllocator allocator)

Method Detail

allocate

public static MappedMemory allocate(File file,
                                    int size)

Allocates memory mapped to a file on disk.

Parameters:

file - The file to which to map memory.

size - The count of the memory to map.

Returns:

The mapped memory.

Throws:

IllegalArgumentException - If count is greater than MAX_SIZE

allocate

public static MappedMemory allocate(File file,
                                    FileChannel.MapMode mode,
                                    int size)

Allocates memory mapped to a file on disk.

Parameters:

file - The file to which to map memory.

mode - The mode with which to map memory.

size - The count of the memory to map.

Returns:

The mapped memory.

Throws:

IllegalArgumentException - If count is greater than MAX_SIZE

flush

public void flush()

Flushes the mapped buffer to disk.

size

public int size()

Description copied from interface: Memory

Returns the memory count.

Specified by:

size in interface Memory

Returns:

The memory count.

free

public void free()

Description copied from interface: Memory

Frees the memory.

Specified by:

free in interface Memory

close

public void close()