net.openhft.chronicle.queue.impl

Interface RollingChronicleQueue

All Superinterfaces:

AutoCloseable, ChronicleQueue, Closeable, StoreReleasable

All Known Implementing Classes:

SingleChronicleQueue

public interface RollingChronicleQueue
extends ChronicleQueue, StoreReleasable

Field Summary

Fields inherited from interface net.openhft.chronicle.queue.ChronicleQueue

TEST_BLOCK_SIZE

Method Summary

Modifier and Type	Method and Description
long	countExcerpts(long fromIndex, long toIndex) The number of excerpts between the indexes, fromIndex inclusive, toIndex exclusive.
int	cycle()
int	deltaCheckpointInterval() Returns the Delta Checkpoint Interval for this ChronicleQueue.
long	entryCount() Counts the number of messages in this queue instance.
long	epoch()
int	firstCycle()
int	indexCount()
int	indexSpacing()
int	lastCycle()
int	nextCycle(int currentCycle, TailerDirection direction) the next available cycle, no cycle will be created by this method, this method is typically used by a tailer to jump to the next cycle when the cycles are not adjacent.
QueueLock	queueLock()
RollCycle	rollCycle() Returns the RollCycle for this ChronicleQueue.
WireStore	storeForCycle(int cycle, long epoch, boolean createIfAbsent)

Methods inherited from interface net.openhft.chronicle.queue.ChronicleQueue

acquireAppender, clear, createAppender, createTailer, createTailer, dump, dump, dump, dumpLastHeader, file, fileAbsolutePath, firstIndex, lastAcknowledgedIndexReplicated, lastAcknowledgedIndexReplicated, lastIndexReplicated, lastIndexReplicated, methodWriter, methodWriterBuilder, refreshDirectlyListing, single, singleBuilder, singleBuilder, singleBuilder, singleBuilder, sourceId, time, wireType

Methods inherited from interface net.openhft.chronicle.core.io.Closeable

close, closeQuietly, closeQuietly, isClosed, notifyClosing

Methods inherited from interface net.openhft.chronicle.queue.impl.StoreReleasable

release

Method Detail

epoch

long epoch()

storeForCycle

@Nullable
WireStore storeForCycle(int cycle,
                                  long epoch,
                                  boolean createIfAbsent)

Parameters:

cycle - the cycle

epoch - an epoch offset as the number of number of milliseconds since January 1, 1970, 00:00:00 GMT

createIfAbsent - create missing stores if true, or return null if missing

Returns:

the WireStore associated with this cycle, or null if !createIfAbsent is false and absent

firstCycle

int firstCycle()

Returns:

the first cycle number found, or Integer.MAX_VALUE is none found.

lastCycle

int lastCycle()

Returns:

the lastCycle available or Integer.MIN_VALUE if none is found.

entryCount

long entryCount()

Counts the number of messages in this queue instance.

Returns:

the number of document excerpts

nextCycle

int nextCycle(int currentCycle,
              @NotNull
              TailerDirection direction)
       throws ParseException

the next available cycle, no cycle will be created by this method, this method is typically used by a tailer to jump to the next cycle when the cycles are not adjacent.

Parameters:

currentCycle - the current cycle

direction - the direction

Returns:

the next available cycle from the current cycle, or -1 if there is no next cycle

Throws:

ParseException

countExcerpts

long countExcerpts(long fromIndex,
                   long toIndex)
            throws IllegalStateException

The number of excerpts between the indexes, fromIndex inclusive, toIndex exclusive.

When fromIndex and toIndex are in different cycles which are not adjacent, this operation can be expensive, as the index count for each intermediate cycle has to be found and calculated. As such, and in this situation, it's not recommended to call this method regularly in latency sensitive systems.

Parameters:

fromIndex - from index, the index provided must exist. To improve performance no checking is carried out to validate if an excerpt exists at this index. ( inclusive )

toIndex - to index, the index provided must exist. To improve performance no checking is carried out to validate if an excerpt exists at this index. ( exclusive )

Returns:

the number of excerpts between the indexes, index1 inclusive, index2 exclusive.

Throws:

IllegalStateException - if the cycle of fromIndex or toIndex can not be ascertained

cycle

int cycle()

Returns:

the current cycle

indexCount

int indexCount()

Returns:

the number of entries in an index meta data entry

indexSpacing

int indexSpacing()

Returns:

the spacing between indexed entries. If 1 then every entry is indexed.

rollCycle

@NotNull
RollCycle rollCycle()

Description copied from interface: ChronicleQueue

Returns the RollCycle for this ChronicleQueue.

Specified by:

rollCycle in interface ChronicleQueue

Returns:

the RollCycle for this ChronicleQueue

See Also:

RollCycle

deltaCheckpointInterval

int deltaCheckpointInterval()

Description copied from interface: ChronicleQueue

Returns the Delta Checkpoint Interval for this ChronicleQueue.

The value returned is always a power of two.

Specified by:

deltaCheckpointInterval in interface ChronicleQueue

Returns:

the checkpointInterval used by delta wire

queueLock

QueueLock queueLock()