org.axonframework.eventhandling.async

Class RetryPolicy

java.lang.Object

org.axonframework.eventhandling.async.RetryPolicy

Direct Known Subclasses:

EventProcessor.ProcessingResult

public abstract class RetryPolicy
extends Object

This policy tells the EventProcessor how it should deal with failed transactions.

• proceed() will tell the scheduler to ignore the failure and continue processing. This policy can be used to indicate sufficient recovery or retrying has been done, or that the error cannot be recovered from, and should be ignored.
• skip() will rollback the Unit of Work and proceed with the next event, effectively skipping the events.
• retryAfter(int, java.util.concurrent.TimeUnit) tells the scheduler to roll back the current Unit of Work and process it again after the given amount of time. All Event Listeners will receive the event again.

Since:

2.0

Author:

Allard Buijze

Constructor Summary

Constructors

Constructor and Description
RetryPolicy()

Method Summary

Methods

Modifier and Type	Method and Description
static RetryPolicy	proceed() Tells the scheduler to ignore the failure continue processing.
abstract boolean	requiresRescheduleEvent() Indicates whether the scheduler should reschedule the failed event.
abstract boolean	requiresRollback() Indicates whether the scheduler should rollback the Unit of Work wrapping the event handling.
static RetryPolicy	retryAfter(int timeout, TimeUnit unit) This policy will roll back the Unit of Work (and the transaction), if any) and reschedule the event for processing.
static RetryPolicy	skip() This policy will roll back the Unit of Work (and the transaction) and skip the event altogether.
abstract long	waitTime() Returns the time the scheduler should wait before continuing processing.

Methods inherited from class java.lang.Object

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

Constructor Detail

RetryPolicy

public RetryPolicy()

Method Detail

proceed

public static RetryPolicy proceed()

Tells the scheduler to ignore the failure continue processing. The Event is processed by the remaining Event Listeners in the Cluster.

Returns:

A RetryPolicy instance requesting the scheduler to proceed with dispatching

skip

public static RetryPolicy skip()

This policy will roll back the Unit of Work (and the transaction) and skip the event altogether. When all listeners support the type of transaction backed by the Unit of Work, this effectively means that the Event can be regarded as not processed. The Event will not be handled by any remaining Event Listeners in the Cluster.

Returns:

A RetryPolicy instance requesting the scheduler to rollback the Unit of Work and continue processing the next Event.

retryAfter

public static RetryPolicy retryAfter(int timeout,
                     TimeUnit unit)

This policy will roll back the Unit of Work (and the transaction), if any) and reschedule the event for processing. The Event will not be handled by any remaining Event Listeners in the Cluster.

Parameters:

timeout - The amount of time to wait before retrying

unit - The unit of time for the timeout

Returns:

a RetryPolicy requesting a rollback and a retry of the failed Event after the given timeout

waitTime

public abstract long waitTime()

Returns the time the scheduler should wait before continuing processing. This value is ignored if requiresRescheduleEvent() returns false.

Returns:

the amount of time, in milliseconds, the scheduler should wait before continuing processing.

requiresRescheduleEvent

public abstract boolean requiresRescheduleEvent()

Indicates whether the scheduler should reschedule the failed event.

Returns:

true if the scheduler should reschedule the failed event, otherwise false

requiresRollback

public abstract boolean requiresRollback()

Indicates whether the scheduler should rollback the Unit of Work wrapping the event handling.

Returns:

true to indicate the scheduler should perform a rollback or false to request a commit.