io.aeron.archive.client

Class RecordingDescriptorPoller

java.lang.Object

io.aeron.archive.client.RecordingDescriptorPoller

All Implemented Interfaces:

ControlledFragmentHandler

public class RecordingDescriptorPoller
extends Object
implements ControlledFragmentHandler

Encapsulate the polling, decoding, dispatching of recording descriptors from an archive.

Nested Class Summary

Nested classes/interfaces inherited from interface io.aeron.logbuffer.ControlledFragmentHandler

ControlledFragmentHandler.Action

Constructor Summary

Constructors

Constructor and Description
RecordingDescriptorPoller(Subscription subscription, ErrorHandler errorHandler, long controlSessionId, int fragmentLimit) Create a poller for a given subscription to an archive for control response messages.

Method Summary

Modifier and Type	Method and Description
long	controlSessionId() Control session id for filtering responses.
boolean	isDispatchComplete() Is the dispatch of descriptors complete?
ControlledFragmentHandler.Action	onFragment(DirectBuffer buffer, int offset, int length, Header header) Callback for handling fragments of data being read from a log.
int	poll() Poll for recording events.
int	remainingRecordCount() Get the number of remaining records are expected.
void	reset(long correlationId, int recordCount, RecordingDescriptorConsumer consumer) Reset the poller to dispatch the descriptors returned from a query.
Subscription	subscription() Get the Subscription used for polling responses.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

RecordingDescriptorPoller

public RecordingDescriptorPoller(Subscription subscription,
                                 ErrorHandler errorHandler,
                                 long controlSessionId,
                                 int fragmentLimit)

Create a poller for a given subscription to an archive for control response messages.

Parameters:

subscription - to poll for new events.

errorHandler - to call for asynchronous errors.

controlSessionId - to filter the responses.

fragmentLimit - to apply for each polling operation.

Method Detail

subscription

public Subscription subscription()

Get the Subscription used for polling responses.

Returns:

the Subscription used for polling responses.

poll

public int poll()

Poll for recording events.

Returns:

the number of fragments read during the operation. Zero if no events are available.

controlSessionId

public long controlSessionId()

Control session id for filtering responses.

Returns:

control session id for filtering responses.

isDispatchComplete

public boolean isDispatchComplete()

Is the dispatch of descriptors complete?

Returns:

true if the dispatch of descriptors complete?

remainingRecordCount

public int remainingRecordCount()

Get the number of remaining records are expected.

Returns:

the number of remaining records are expected.

reset

public void reset(long correlationId,
                  int recordCount,
                  RecordingDescriptorConsumer consumer)

Reset the poller to dispatch the descriptors returned from a query.

Parameters:

correlationId - for the response.

recordCount - of descriptors to expect.

consumer - to which the recording descriptors are to be dispatched.

onFragment

public ControlledFragmentHandler.Action onFragment(DirectBuffer buffer,
                                                   int offset,
                                                   int length,
                                                   Header header)

Description copied from interface: ControlledFragmentHandler

Callback for handling fragments of data being read from a log.

Within this callback reentrant calls to the Aeron client are not permitted and will result in undefined behaviour.

Specified by:

onFragment in interface ControlledFragmentHandler

Parameters:

buffer - containing the data.

offset - at which the data begins.

length - of the data in bytes.

header - representing the meta data for the data.

Returns:

The action to be taken with regard to the stream position after the callback.

toString

public String toString()

Overrides:

toString in class Object