Package org.axonframework.commandhandling.gateway

Class AbstractRetryScheduler

java.lang.Object

org.axonframework.commandhandling.gateway.AbstractRetryScheduler

All Implemented Interfaces:

RetryScheduler

Direct Known Subclasses:

ExponentialBackOffIntervalRetryScheduler, IntervalRetryScheduler

public abstract class AbstractRetryScheduler
extends Object
implements RetryScheduler

An abstract base class for RetrySchedulers. This class provides methods to do the actual rescheduling and decides if a given Throwable is explicitly transient.

Since:

4.2

Author:

Bert Laverman

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AbstractRetryScheduler.Builder<B extends AbstractRetryScheduler.Builder>	A builder class for the RetryScheduler implementations.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractRetryScheduler(AbstractRetryScheduler.Builder builder)	Construct the AbstractRetryScheduler from its builder.

Method Summary

Modifier and Type	Method	Description
protected abstract long	computeRetryInterval(CommandMessage commandMessage, RuntimeException lastFailure, List<Class<? extends Throwable>[]> failures)	Compute the amount of milliseconds delay until the next retry, given the information passed.
protected boolean	isExplicitlyNonTransient(Throwable failure)	Indicates whether the given failure is clearly non-transient.
protected boolean	scheduleRetry(Runnable commandDispatch, long interval)	Schedule the provided task to run after the given interval.
boolean	scheduleRetry(CommandMessage commandMessage, RuntimeException lastFailure, List<Class<? extends Throwable>[]> failures, Runnable dispatchTask)	This is the entrypoint of the RetryScheduler.

Methods inherited from class java.lang.Object

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

Constructor Details

AbstractRetryScheduler

protected AbstractRetryScheduler(AbstractRetryScheduler.Builder builder)

Construct the AbstractRetryScheduler from its builder.

Parameters:

builder - the AbstractRetryScheduler.Builder

Method Details

scheduleRetry

protected boolean scheduleRetry(Runnable commandDispatch,
 long interval)

Schedule the provided task to run after the given interval.

Parameters:

commandDispatch - the Runnable to schedule.

interval - the number of milliseconds delay.

Returns:

true if the task was accepted for scheduling, false otherwise.

computeRetryInterval

protected abstract long computeRetryInterval(CommandMessage commandMessage,
 RuntimeException lastFailure,
 List<Class<? extends Throwable>[]> failures)

Compute the amount of milliseconds delay until the next retry, given the information passed.

Parameters:

commandMessage - the command that was sent (and failed).

lastFailure - the last failure that caused this retry scheduler to be called.

failures - a List of all failures up to now.

Returns:

the number of milliseconds to wait until retrying.

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.

In this implementation, given failure (and its causes) is tested against configured composable nonTransientFailurePredicate. By default, nonTransientFailurePredicate is configured only with AxonNonTransientExceptionClassesPredicate.

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.

scheduleRetry

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

This is the entrypoint of the RetryScheduler. This default implementation checks if the last failure was transient, and if so reschedules a command dispatch.

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 that performs the actual dispatching.

Returns:

true if rescheduling succeeded, false if otherwise.