com.datastax.driver.core.policies

Class ExponentialReconnectionPolicy

java.lang.Object

com.datastax.driver.core.policies.ExponentialReconnectionPolicy

All Implemented Interfaces:

ReconnectionPolicy

public class ExponentialReconnectionPolicy
extends Object
implements ReconnectionPolicy

A reconnection policy that waits exponentially longer between each reconnection attempt (but keeps a constant delay once a maximum delay is reached).

Nested Class Summary

Nested classes/interfaces inherited from interface com.datastax.driver.core.policies.ReconnectionPolicy

ReconnectionPolicy.ReconnectionSchedule

Constructor Summary

Constructors

Constructor and Description
ExponentialReconnectionPolicy(long baseDelayMs, long maxDelayMs) Creates a reconnection policy waiting exponentially longer for each new attempt.

Method Summary

Modifier and Type	Method and Description
void	close() Gets invoked at cluster shutdown.
long	getBaseDelayMs() The base delay in milliseconds for this policy (e.g.
long	getMaxDelayMs() The maximum delay in milliseconds between reconnection attempts for this policy.
void	init(Cluster cluster) Gets invoked at cluster startup.
ReconnectionPolicy.ReconnectionSchedule	newSchedule() A new schedule that used an exponentially growing delay between reconnection attempts.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExponentialReconnectionPolicy

public ExponentialReconnectionPolicy(long baseDelayMs,
                                     long maxDelayMs)

Creates a reconnection policy waiting exponentially longer for each new attempt.

Parameters:

baseDelayMs - the base delay in milliseconds to use for the schedules created by this policy.

maxDelayMs - the maximum delay to wait between two attempts.

Method Detail

getBaseDelayMs

public long getBaseDelayMs()

The base delay in milliseconds for this policy (e.g. the delay before the first reconnection attempt).

Returns:

the base delay in milliseconds for this policy.

getMaxDelayMs

public long getMaxDelayMs()

The maximum delay in milliseconds between reconnection attempts for this policy.

Returns:

the maximum delay in milliseconds between reconnection attempts for this policy.

newSchedule

public ReconnectionPolicy.ReconnectionSchedule newSchedule()

A new schedule that used an exponentially growing delay between reconnection attempts.

For this schedule, reconnection attempt i will be tried Math.min(2^(i-1) * getBaseDelayMs(), getMaxDelayMs()) milliseconds after the previous one.

Specified by:

newSchedule in interface ReconnectionPolicy

Returns:

the newly created schedule.

init

public void init(Cluster cluster)

Description copied from interface: ReconnectionPolicy

Gets invoked at cluster startup.

Specified by:

init in interface ReconnectionPolicy

Parameters:

cluster - the cluster that this policy is associated with.

close

public void close()

Description copied from interface: ReconnectionPolicy

Gets invoked at cluster shutdown.

This gives the policy the opportunity to perform some cleanup, for instance stop threads that it might have started.

Specified by:

close in interface ReconnectionPolicy