io.druid.server.coordination

Class SegmentChangeRequestHistory

java.lang.Object

io.druid.server.coordination.SegmentChangeRequestHistory

public class SegmentChangeRequestHistory
extends Object

This class keeps a bounded list of segment updates made on the server such as adding/dropping segments. Clients call addSegmentChangeRequest(DataSegmentChangeRequest) or addSegmentChangeRequests(List) to add segment updates. Clients call ListenableFuture getRequestsSince(final Counter counter) to get segment updates since given counter.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	SegmentChangeRequestHistory.Counter

Constructor Summary

Constructors

Constructor and Description
SegmentChangeRequestHistory()
SegmentChangeRequestHistory(int maxSize)

Method Summary

Modifier and Type	Method and Description
void	addSegmentChangeRequest(DataSegmentChangeRequest request) Add single segment change update.
void	addSegmentChangeRequests(List<DataSegmentChangeRequest> requests) Add batch of segment changes update.
SegmentChangeRequestHistory.Counter	getLastCounter()
com.google.common.util.concurrent.ListenableFuture<SegmentChangeRequestsSnapshot>	getRequestsSince(SegmentChangeRequestHistory.Counter counter) Returns a Future that , on completion, returns list of segment updates and associated counter.

Methods inherited from class java.lang.Object

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

Constructor Detail

SegmentChangeRequestHistory

public SegmentChangeRequestHistory()

SegmentChangeRequestHistory

public SegmentChangeRequestHistory(int maxSize)

Method Detail

addSegmentChangeRequests

public void addSegmentChangeRequests(List<DataSegmentChangeRequest> requests)

Add batch of segment changes update.

addSegmentChangeRequest

public void addSegmentChangeRequest(DataSegmentChangeRequest request)

Add single segment change update.

getRequestsSince

public com.google.common.util.concurrent.ListenableFuture<SegmentChangeRequestsSnapshot> getRequestsSince(SegmentChangeRequestHistory.Counter counter)

Returns a Future that , on completion, returns list of segment updates and associated counter. If there are no update since given counter then Future completion waits till an updates is provided. If counter is older than max number of changes maintained then SegmentChangeRequestsSnapshot is returned with resetCounter set to True. If there were no updates to provide immediately then a future is created and returned to caller. This future is added to the "waitingFutures" list and all the futures in the list get resolved as soon as a segment update is provided.

getLastCounter

public SegmentChangeRequestHistory.Counter getLastCounter()