Package org.apache.cassandra.io.util

Class Memory

java.lang.Object

org.apache.cassandra.io.util.Memory

All Implemented Interfaces:

AutoCloseable, ReadableMemory

Direct Known Subclasses:

RefCountedMemory, SafeMemory

public class Memory
extends Object
implements AutoCloseable, ReadableMemory

An off-heap region of memory that must be manually free'd when no longer needed. It uses Little Endian (LE).

Field Summary

Fields

Modifier and Type	Field	Description
static final ByteBuffer[]	NO_BYTE_BUFFERS
protected long	peer
protected final long	size

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Memory(long bytes)
protected	Memory(Memory copyOf)

Method Summary

Modifier and Type	Method	Description
static Memory	allocate(long bytes)
ByteBuffer	asByteBuffer(long offset, int length)
ByteBuffer[]	asByteBuffers(long offset, long length)
protected void	checkBounds(long start, long end)
void	close()
Memory	copy(long newSize)
boolean	equals(Object o)
void	free()
byte	getByte(long offset)
void	getBytes(long memoryOffset, byte[] buffer, int bufferOffset, int count)	Transfers count bytes from Memory starting at memoryOffset to buffer starting at bufferOffset
int	getInt(long offset)
long	getLong(long offset)
void	put(long trgOffset, Memory memory, long srcOffset, long size)
void	setByte(long offset, byte b)
void	setByteBuffer(ByteBuffer buffer, long offset, int length)
void	setBytes(long memoryOffset, byte[] buffer, int bufferOffset, int count)	Transfers count bytes from buffer to Memory
void	setBytes(long memoryOffset, ByteBuffer buffer)
void	setInt(long offset, int l)
void	setLong(long offset, long l)
void	setMemory(long offset, long bytes, byte b)
long	size()
String	toString()
protected static String	toString(long peer, long size)

Methods inherited from class java.lang.Object

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

Field Details

NO_BYTE_BUFFERS

public static final ByteBuffer[] NO_BYTE_BUFFERS

peer

protected long peer

size

protected final long size

Constructor Details

Memory

protected Memory(long bytes)

Memory

protected Memory(Memory copyOf)

Method Details

allocate

public static Memory allocate(long bytes)

setByte

public void setByte(long offset,
 byte b)

setMemory

public void setMemory(long offset,
 long bytes,
 byte b)

setLong

public void setLong(long offset,
 long l)

setInt

public void setInt(long offset,
 int l)

setBytes

public void setBytes(long memoryOffset,
 ByteBuffer buffer)

setBytes

public void setBytes(long memoryOffset,
 byte[] buffer,
 int bufferOffset,
 int count)

Transfers count bytes from buffer to Memory

Parameters:

memoryOffset - start offset in the memory

buffer - the data buffer

bufferOffset - start offset of the buffer

count - number of bytes to transfer

getByte

public byte getByte(long offset)

getLong

public long getLong(long offset)

getInt

public int getInt(long offset)

getBytes

public void getBytes(long memoryOffset,
 byte[] buffer,
 int bufferOffset,
 int count)

Transfers count bytes from Memory starting at memoryOffset to buffer starting at bufferOffset

Parameters:

memoryOffset - start offset in the memory

buffer - the data buffer

bufferOffset - start offset of the buffer

count - number of bytes to transfer

checkBounds

@Inline
protected void checkBounds(long start,
 long end)

put

public void put(long trgOffset,
 Memory memory,
 long srcOffset,
 long size)

copy

public Memory copy(long newSize)

free

public void free()

close

public void close()

Specified by:

close in interface AutoCloseable

size

public long size()

equals

public boolean equals(Object o)

Overrides:

equals in class Object

asByteBuffers

public ByteBuffer[] asByteBuffers(long offset,
 long length)

Specified by:

asByteBuffers in interface ReadableMemory

asByteBuffer

public ByteBuffer asByteBuffer(long offset,
 int length)

setByteBuffer

public void setByteBuffer(ByteBuffer buffer,
 long offset,
 int length)

toString

public String toString()

Overrides:

toString in class Object

toString

protected static String toString(long peer,
 long size)