Package com.google.cloud.spanner.spi.v1

Class PowerOfTwoReplicaSelector

java.lang.Object

com.google.cloud.spanner.spi.v1.PowerOfTwoReplicaSelector

All Implemented Interfaces:

ReplicaSelector

@InternalApi
@BetaApi
public class PowerOfTwoReplicaSelector
extends Object
implements ReplicaSelector

Implementation of ReplicaSelector using the "Power of 2 Random Choices" strategy.

Constructor Summary

Constructors

Constructor	Description
PowerOfTwoReplicaSelector()

Method Summary

Modifier and Type	Method	Description
ChannelEndpoint	select(List<ChannelEndpoint> candidates, Function<ChannelEndpoint,Double> scoreLookup)	Selects a replica from the given list of candidates.

Methods inherited from class java.lang.Object

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

Constructor Details

PowerOfTwoReplicaSelector

public PowerOfTwoReplicaSelector()

Method Details

select

public ChannelEndpoint select(List<ChannelEndpoint> candidates,
 Function<ChannelEndpoint,Double> scoreLookup)

Description copied from interface: ReplicaSelector

Selects a replica from the given list of candidates.

Specified by:

select in interface ReplicaSelector

Parameters:

candidates - the list of eligible candidates.

scoreLookup - a function to look up the latency score for a candidate.

Returns:

the selected candidate, or null if the list is empty.