net.openhft.chronicle.queue.impl

Class AbstractChronicleQueue

java.lang.Object

net.openhft.chronicle.queue.impl.AbstractChronicleQueue

All Implemented Interfaces:

Closeable, AutoCloseable, ChronicleQueue

public abstract class AbstractChronicleQueue
extends Object
implements ChronicleQueue

Field Summary

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

MINUS_1_40BIT

Constructor Summary

Constructors

Constructor and Description
AbstractChronicleQueue()

Method Summary

Modifier and Type	Method and Description
void	clear() Remove all the entries in the queue.
void	close()
ExcerptAppender	createAppender() An Appender can be used to writeBytes new excerpts sequentially to the upper.
Excerpt	createExcerpt() An Excerpt can be used access entries randomly and optionally change them.
ExcerptTailer	createTailer() A Tailer can be used to read sequentially from the lower of a given position.
protected abstract long	cycle()
abstract long	epoch()
long	firstIndex()
long	lastIndex()
String	name()
protected abstract void	release(WireStore store)
long	size()
protected abstract WireStore	storeForCycle(long cycle, long epoch)
net.openhft.chronicle.wire.WireType	wireType()

Methods inherited from class java.lang.Object

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

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

index, toCycle, toSequenceNumber

Constructor Detail

AbstractChronicleQueue

public AbstractChronicleQueue()

Method Detail

name

@NotNull
public String name()

Specified by:

name in interface ChronicleQueue

Returns:

A descriptive name for this queue which can be used for logging.

epoch

public abstract long epoch()

createAppender

@NotNull
public ExcerptAppender createAppender()

Description copied from interface: ChronicleQueue

An Appender can be used to writeBytes new excerpts sequentially to the upper.

Specified by:

createAppender in interface ChronicleQueue

Returns:

ExcerptAppender

createTailer

@NotNull
public ExcerptTailer createTailer()
                                    throws IOException

Description copied from interface: ChronicleQueue

A Tailer can be used to read sequentially from the lower of a given position.

Specified by:

createTailer in interface ChronicleQueue

Returns:

ExcerptTailer

Throws:

IOException - if an IO problem occurs

createExcerpt

@NotNull
public Excerpt createExcerpt()

Description copied from interface: ChronicleQueue

An Excerpt can be used access entries randomly and optionally change them.

Specified by:

createExcerpt in interface ChronicleQueue

Returns:

Excerpt

size

public long size()

Specified by:

size in interface ChronicleQueue

Returns:

The current estimated number of entries.

clear

public void clear()

Description copied from interface: ChronicleQueue

Remove all the entries in the queue.

Specified by:

clear in interface ChronicleQueue

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

firstIndex

public long firstIndex()

Specified by:

firstIndex in interface ChronicleQueue

Returns:

the lowest valid index available, or sequenceNumber=0 if none are found

lastIndex

public long lastIndex()

Specified by:

lastIndex in interface ChronicleQueue

Returns:

the highest valid index immediately available. Or -1 if none available. The lowest 40bits of the index refer to the sequence number with the cycle, giving a maximum of 1099511627776 excerpt per cycle. Each cycle has its own file. Each file holds its own index. You can discard the old files ( if they are no longer used ). The other highest 24 bits
 of the index are used for the cycle number (this equates to the filename), giving a maximum
 of 16777216 cycles ( aka files )

wireType

@NotNull
public net.openhft.chronicle.wire.WireType wireType()

Specified by:

wireType in interface ChronicleQueue

Returns:

the type of wire used, for example TEXT_WIRE or BINARY WIRE

storeForCycle

@NotNull
protected abstract WireStore storeForCycle(long cycle,
                                                    long epoch)

Parameters:

cycle - the cycle

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

Returns:

the WireStore associated with this cycle

release

protected abstract void release(@NotNull
                                WireStore store)

Parameters:

store - the store to release

cycle

protected abstract long cycle()

Returns:

the current cycle