org.axonframework.commandhandling.gateway

Class IntervalRetryScheduler

java.lang.Object

org.axonframework.commandhandling.gateway.IntervalRetryScheduler

All Implemented Interfaces:

RetryScheduler

public class IntervalRetryScheduler
extends Object
implements RetryScheduler

RetryScheduler implementation that retries commands at regular intervals when they fail because of an exception that is not explicitly non-transient. Checked exceptions are considered non-transient and will not result in a retry.

Since:

2.0

Author:

Allard Buijze

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	IntervalRetryScheduler.Builder Builder class to instantiate a IntervalRetryScheduler.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	IntervalRetryScheduler(IntervalRetryScheduler.Builder builder) Instantiate a IntervalRetryScheduler based on the fields contained in the IntervalRetryScheduler.Builder.

Method Summary

Modifier and Type	Method and Description
static IntervalRetryScheduler.Builder	builder() Instantiate a Builder to be able to create a IntervalRetryScheduler.
protected boolean	isExplicitlyNonTransient(Throwable failure) Indicates whether the given failure is clearly non-transient.
boolean	scheduleRetry(CommandMessage commandMessage, RuntimeException lastFailure, List<Class<? extends Throwable>[]> failures, Runnable dispatchTask) Inspect the given commandMessage that failed with given lastFailure.

Methods inherited from class java.lang.Object

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

Constructor Detail

IntervalRetryScheduler

protected IntervalRetryScheduler(IntervalRetryScheduler.Builder builder)

Instantiate a IntervalRetryScheduler based on the fields contained in the IntervalRetryScheduler.Builder.

Will assert that the retryInterval and maxRetryCount are positive numbers, and that the ScheduledExecutorService is not null. If any of these does not hold, an AxonConfigurationException will be thrown.

Parameters:

builder - the IntervalRetryScheduler.Builder used to instantiate a IntervalRetryScheduler instance

Method Detail

builder

public static IntervalRetryScheduler.Builder builder()

Instantiate a Builder to be able to create a IntervalRetryScheduler.

The default for retryInterval is set to 100ms, while maxRetryCount gets a single retry. The retryInterval, maxRetryCount and ScheduledExecutorService are hard requirements and as such should be provided.

Returns:

a Builder to be able to create a IntervalRetryScheduler

scheduleRetry

public boolean scheduleRetry(CommandMessage commandMessage,
                             RuntimeException lastFailure,
                             List<Class<? extends Throwable>[]> failures,
                             Runnable dispatchTask)

Description copied from interface: RetryScheduler

Inspect the given commandMessage that failed with given lastFailure. The given failures provides a list of previous failures known for this command. The commandDispatch task can be used to schedule the command for dispatching.

The return value of this method indicates whether the command has been scheduled for a retry. When true, the original callbacks should not be invoked, as command execution is subject to a retry. When false, the failure is interpreted as terminal and the callback will be invoked with the last failure recorded.

If the implementation throws an Exception, that exception is passed as the failure to the original callback.

Specified by:

scheduleRetry in interface RetryScheduler

Parameters:

commandMessage - The Command Message being dispatched

lastFailure - The last failure recorded for this command

failures - A condensed view of all known failures of this command. Each element in the array represents the cause of the element preceding it.

dispatchTask - The task to be executed to retry a command

Returns:

true if the command has been rescheduled, otherwise false

isExplicitlyNonTransient

protected boolean isExplicitlyNonTransient(Throwable failure)

Indicates whether the given failure is clearly non-transient. That means, whether the failure explicitly states that a retry of the same Command would result in the same failure to occur again.

Parameters:

failure - the exception that occurred while processing a command

Returns:

true if the exception is clearly non-transient and the command should not be retried, or false when the command has a chance of succeeding if it retried.