org.camunda.bpm.client.backoff

Class ExponentialBackoffStrategy

java.lang.Object

org.camunda.bpm.client.backoff.ExponentialBackoffStrategy

All Implemented Interfaces:

BackoffStrategy

public class ExponentialBackoffStrategy
extends Object
implements BackoffStrategy

Provides an exponential backoff strategy.

Author:

Nikola Koevski

Field Summary

Fields

Modifier and Type	Field and Description
protected float	factor
protected long	initTime
protected int	level
protected long	maxTime

Constructor Summary

Constructors

Constructor and Description
ExponentialBackoffStrategy()
ExponentialBackoffStrategy(long initTime, float factor, long maxTime)

Method Summary

Modifier and Type	Method and Description
long	calculateBackoffTime() Calculates the back off time and is invoked after BackoffStrategy.reconfigure(List).
void	reconfigure(List<ExternalTask> externalTasks) Reconfigures the back off strategy based on the fetched external tasks and is invoked before BackoffStrategy.calculateBackoffTime().

Methods inherited from class java.lang.Object

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

Field Detail

initTime

protected long initTime

factor

protected float factor

level

protected int level

maxTime

protected long maxTime

Constructor Detail

ExponentialBackoffStrategy

public ExponentialBackoffStrategy()

ExponentialBackoffStrategy

public ExponentialBackoffStrategy(long initTime,
                                  float factor,
                                  long maxTime)

Parameters:

initTime - in milliseconds for which the client is suspended after the first request

factor - is the base of the power by which the waiting time increases

maxTime - in milliseconds for which the client can be suspended

Method Detail

reconfigure

public void reconfigure(List<ExternalTask> externalTasks)

Description copied from interface: BackoffStrategy

Reconfigures the back off strategy based on the fetched external tasks and is invoked before BackoffStrategy.calculateBackoffTime().

The implementation might count the amount of invocations and realize a strategy reset.

Specified by:

reconfigure in interface BackoffStrategy

Parameters:

externalTasks - which have been fetched

calculateBackoffTime

public long calculateBackoffTime()

Description copied from interface: BackoffStrategy

Calculates the back off time and is invoked after BackoffStrategy.reconfigure(List).

Specified by:

calculateBackoffTime in interface BackoffStrategy

Returns:

the back off time between fetch and lock requests in milliseconds