org.axonframework.commandhandling.conflictresolution

Class DefaultConflictResolver

java.lang.Object

org.axonframework.commandhandling.conflictresolution.DefaultConflictResolver

All Implemented Interfaces:

ConflictResolver

public class DefaultConflictResolver
extends Object
implements ConflictResolver

Implementation of a ConflictResolver that fetches any unseen changes from the EventStore.

Author:

Rene de Waele

Constructor Summary

Constructors

Constructor and Description
DefaultConflictResolver(EventStore eventStore, String aggregateIdentifier, long expectedVersion, long actualVersion) Initializes a DefaultConflictResolver using the given eventStore to load unseen events since given expectedVersion.

Method Summary

Modifier and Type	Method and Description
<T extends Exception> void	detectConflicts(Predicate<List<DomainEventMessage<?>>> predicate, ContextAwareConflictExceptionSupplier<T> exceptionSupplier) Resolve conflicts between unseen changes made to the aggregate and new changes that are about to be made.
void	ensureConflictsResolved() Ensure that conflicts have been resolved (via (detectConflicts(java.util.function.Predicate<java.util.List<org.axonframework.eventsourcing.DomainEventMessage<?>>>, org.axonframework.commandhandling.conflictresolution.ContextAwareConflictExceptionSupplier<T>)).

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.axonframework.commandhandling.conflictresolution.ConflictResolver

detectConflicts, detectConflicts

Constructor Detail

DefaultConflictResolver

public DefaultConflictResolver(EventStore eventStore,
                               String aggregateIdentifier,
                               long expectedVersion,
                               long actualVersion)

Initializes a DefaultConflictResolver using the given eventStore to load unseen events since given expectedVersion.

Parameters:

eventStore - the event store to load unseen events

aggregateIdentifier - the identifier of the event sourced aggregate that is being modified

expectedVersion - the last seen version (sequence number) of the aggregate

actualVersion - the actual version (sequence number) of the aggregate

Method Detail

detectConflicts

public <T extends Exception> void detectConflicts(Predicate<List<DomainEventMessage<?>>> predicate,
                                                  ContextAwareConflictExceptionSupplier<T> exceptionSupplier)
                                           throws T extends Exception

Description copied from interface: ConflictResolver

Resolve conflicts between unseen changes made to the aggregate and new changes that are about to be made.

Conflicts are detected using the given predicate. If the Predicate.test(Object) method returns true a conflict is registered. If a conflict is registered an instance of ConflictingModificationException (or subtype) is thrown immediately. The cause of the exception is supplied by the given causeSupplier (supplying a null cause is allowed).

Specified by:

detectConflicts in interface ConflictResolver

Parameters:

predicate - test for conflicting unseen changes. Returns true if there is a conflict.

exceptionSupplier - exception to throw when a conflict is detected

Throws:

T - The type of exception to throw when conflicts are detected

T extends Exception

ensureConflictsResolved

public void ensureConflictsResolved()

Ensure that conflicts have been resolved (via (detectConflicts(java.util.function.Predicate<java.util.List<org.axonframework.eventsourcing.DomainEventMessage<?>>>, org.axonframework.commandhandling.conflictresolution.ContextAwareConflictExceptionSupplier<T>)). If not, an instance of ConflictingModificationException (or subtype) should be thrown if there have been any unseen changes.