org.jctools.channels.spsc

Class SpscOffHeapFixedSizeRingBuffer

java.lang.Object

org.jctools.channels.OffHeapFixedMessageSizeRingBuffer

org.jctools.channels.spsc.SpscOffHeapFixedSizeRingBuffer

Direct Known Subclasses:

DemoProxyResult, SpscChannelConsumer, SpscChannelProducer

public class SpscOffHeapFixedSizeRingBuffer
extends OffHeapFixedMessageSizeRingBuffer

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

Field Summary

Fields

Modifier and Type	Field and Description
static long	EOF

Fields inherited from class org.jctools.channels.OffHeapFixedMessageSizeRingBuffer

bufferAddress, consumerIndexAddress, 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	SpscOffHeapFixedSizeRingBuffer(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.
	SpscOffHeapFixedSizeRingBuffer(int capacity, int messageSize)

Method Summary

Modifier and Type	Method and Description
static int	getLookaheadStep(int capacity)
protected long	readAcquire()
protected void	readRelease(long offset)
protected long	writeAcquire()
protected void	writeRelease(long offset)
protected void	writeRelease(long offset, int type)

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

Field Detail

EOF

public static final long EOF

See Also:

Constant Field Values

Constructor Detail

SpscOffHeapFixedSizeRingBuffer

public SpscOffHeapFixedSizeRingBuffer(int capacity,
                                      int messageSize)

SpscOffHeapFixedSizeRingBuffer

protected SpscOffHeapFixedSizeRingBuffer(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 - in messages, actual capacity will be

messageSize -

Method Detail

getLookaheadStep

public static int getLookaheadStep(int capacity)

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

writeRelease

protected final void writeRelease(long offset,
                                  int type)

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