org.jctools.channels.mpsc

Class MpscOffHeapFixedSizeRingBuffer

java.lang.Object

org.jctools.channels.OffHeapFixedMessageSizeRingBuffer

org.jctools.channels.mpsc.MpscOffHeapFixedSizeRingBuffer

Direct Known Subclasses:

MpscChannelConsumer, MpscChannelProducer

public class MpscOffHeapFixedSizeRingBuffer
extends OffHeapFixedMessageSizeRingBuffer

Channel protocol: - Fixed message size - 'null' indicator in message preceding byte (potentially use same for type mapping in future) - Use Vyukov MPMC like algorithm relying on indicator to support in place detection of next element existence

Field Summary

Fields inherited from class org.jctools.channels.OffHeapFixedMessageSizeRingBuffer

bufferAddress, consumerIndexAddress, EOF, HEADER_SIZE, mask, MESSAGE_INDICATOR_SIZE, messageSize, producerIndexAddress, READ_ACQUIRE_INDICATOR, READ_RELEASE_INDICATOR, WRITE_ACQUIRE_INDICATOR, WRITE_RELEASE_INDICATOR

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	MpscOffHeapFixedSizeRingBuffer(java.nio.ByteBuffer buff, int capacity, boolean isProducer, boolean isConsumer, boolean initialize, int messageSize) This is to be used for an IPC queue with the direct buffer used being a memory mapped file.
	MpscOffHeapFixedSizeRingBuffer(int capacity, int messageSize)

Method Summary

Modifier and Type	Method and Description
private boolean	casProducerIndex(long expected, long update)
protected long	readAcquire()
protected void	readRelease(long offset)
protected long	writeAcquire()
protected void	writeRelease(long offset)

Methods inherited from class org.jctools.channels.OffHeapFixedMessageSizeRingBuffer

capacity, getRequiredBufferSize, isEmpty, isReadReleased, lpConsumerIndex, lpProducerIndex, lvConsumerIndex, lvProducerIndex, offsetForIndex, offsetForIndex, readAcquireState, readReleaseState, size, soConsumerIndex, soProducerIndex, writeAcquireState, writeReleaseState

Methods inherited from class java.lang.Object

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

Constructor Detail

MpscOffHeapFixedSizeRingBuffer

public MpscOffHeapFixedSizeRingBuffer(int capacity,
                                      int messageSize)

MpscOffHeapFixedSizeRingBuffer

protected MpscOffHeapFixedSizeRingBuffer(java.nio.ByteBuffer buff,
                                         int capacity,
                                         boolean isProducer,
                                         boolean isConsumer,
                                         boolean initialize,
                                         int messageSize)

This is to be used for an IPC queue with the direct buffer used being a memory mapped file.

Parameters:

buff -

capacity -

Method Detail

writeAcquire

protected final long writeAcquire()

Specified by:

writeAcquire in class OffHeapFixedMessageSizeRingBuffer

Returns:

a base address for a message acquired to be written, or EOF if none is available

writeRelease

protected final void writeRelease(long offset)

Specified by:

writeRelease in class OffHeapFixedMessageSizeRingBuffer

Parameters:

offset - the base address of a message that we are done writing and can be read now

readAcquire

protected final long readAcquire()

Specified by:

readAcquire in class OffHeapFixedMessageSizeRingBuffer

Returns:

a base address for a message acquired to be read, or EOF if none is available

readRelease

protected final void readRelease(long offset)

Specified by:

readRelease in class OffHeapFixedMessageSizeRingBuffer

Parameters:

offset - the base address of a message that we are done reading and can be overwritten now

casProducerIndex

private boolean casProducerIndex(long expected,
                                 long update)