org.apache.bookkeeper.client

Class DefaultSpeculativeRequestExecutionPolicy

java.lang.Object

org.apache.bookkeeper.client.DefaultSpeculativeRequestExecutionPolicy

All Implemented Interfaces:

SpeculativeRequestExecutionPolicy

public class DefaultSpeculativeRequestExecutionPolicy
extends java.lang.Object
implements SpeculativeRequestExecutionPolicy

A default implementation of SpeculativeRequestExecutionPolicy.

The policy issues speculative requests in a backoff way. The time between two speculative requests are between firstSpeculativeRequestTimeout and maxSpeculativeRequestTimeout.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) float	backoffMultiplier
(package private) int	firstSpeculativeRequestTimeout
(package private) int	maxSpeculativeRequestTimeout

Constructor Summary

Constructors

Constructor and Description
DefaultSpeculativeRequestExecutionPolicy(int firstSpeculativeRequestTimeout, int maxSpeculativeRequestTimeout, float backoffMultiplier)

Method Summary

Modifier and Type	Method and Description
java.util.concurrent.ScheduledFuture<?>	initiateSpeculativeRequest(java.util.concurrent.ScheduledExecutorService scheduler, SpeculativeRequestExecutor requestExecutor) Initialize the speculative request execution policy.

Methods inherited from class java.lang.Object

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

Field Detail

firstSpeculativeRequestTimeout

final int firstSpeculativeRequestTimeout

maxSpeculativeRequestTimeout

final int maxSpeculativeRequestTimeout

backoffMultiplier

final float backoffMultiplier

Constructor Detail

DefaultSpeculativeRequestExecutionPolicy

public DefaultSpeculativeRequestExecutionPolicy(int firstSpeculativeRequestTimeout,
                                                int maxSpeculativeRequestTimeout,
                                                float backoffMultiplier)

Method Detail

initiateSpeculativeRequest

public java.util.concurrent.ScheduledFuture<?> initiateSpeculativeRequest(java.util.concurrent.ScheduledExecutorService scheduler,
                                                                          SpeculativeRequestExecutor requestExecutor)

Initialize the speculative request execution policy.

Specified by:

initiateSpeculativeRequest in interface SpeculativeRequestExecutionPolicy

Parameters:

scheduler - The scheduler service to issue the speculative request

requestExecutor - The executor is used to issue the actual speculative requests

Returns:

ScheduledFuture, in case caller needs to cancel it.