org.agrona.concurrent.ringbuffer

Class RingBufferDescriptor

java.lang.Object

org.agrona.concurrent.ringbuffer.RingBufferDescriptor

public final class RingBufferDescriptor
extends Object

Layout description for the underlying buffer used by a RingBuffer. The buffer consists of a ring of messages which is a power of 2 in size, followed by a trailer section containing state information for the producers and consumers of the ring.

Field Summary

Fields

Modifier and Type	Field and Description
static int	CONSUMER_HEARTBEAT_OFFSET Offset within the trailer for where the consumer heartbeat time value is stored.
static int	CORRELATION_COUNTER_OFFSET Offset within the trailer for where the correlation counter value is stored.
static int	HEAD_CACHE_POSITION_OFFSET Offset within the trailer for where the head cache value is stored.
static int	HEAD_POSITION_OFFSET Offset within the trailer for where the head value is stored.
static int	TAIL_POSITION_OFFSET Offset within the trailer for where the tail value is stored.
static int	TRAILER_LENGTH Total length of the trailer in bytes.

Method Summary

Modifier and Type	Method and Description
static int	checkCapacity(int capacity, int minCapacity) Check the buffer capacity is the correct size (a power of 2 + TRAILER_LENGTH) and that it satisfies minimum capacity size.

Methods inherited from class java.lang.Object

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

Field Detail

TAIL_POSITION_OFFSET

public static final int TAIL_POSITION_OFFSET

Offset within the trailer for where the tail value is stored.

HEAD_CACHE_POSITION_OFFSET

public static final int HEAD_CACHE_POSITION_OFFSET

Offset within the trailer for where the head cache value is stored.

HEAD_POSITION_OFFSET

public static final int HEAD_POSITION_OFFSET

Offset within the trailer for where the head value is stored.

CORRELATION_COUNTER_OFFSET

public static final int CORRELATION_COUNTER_OFFSET

Offset within the trailer for where the correlation counter value is stored.

CONSUMER_HEARTBEAT_OFFSET

public static final int CONSUMER_HEARTBEAT_OFFSET

Offset within the trailer for where the consumer heartbeat time value is stored.

TRAILER_LENGTH

public static final int TRAILER_LENGTH

Total length of the trailer in bytes.

Method Detail

checkCapacity

public static int checkCapacity(int capacity,
                                int minCapacity)

Check the buffer capacity is the correct size (a power of 2 + TRAILER_LENGTH) and that it satisfies minimum capacity size.

Parameters:

capacity - to be checked.

minCapacity - minimum required capacity of the ring buffer.

Returns:

the capacity to store the data in the ring buffer, i.e. capacity - TRAILER_LENGTH.

Throws:

IllegalArgumentException - if the buffer capacity is incorrect.