Author: danhaywood
Date: Wed Nov 19 08:51:11 2014
New Revision: 1640504
URL: http://svn.apache.org/r1640504
Log:
tutorial
Modified:
isis/site/trunk/content/intro/tutorials/apacheconeu-2014.md
isis/site/trunk/content/reference/services/event-bus-service.md
Modified: isis/site/trunk/content/intro/tutorials/apacheconeu-2014.md
URL:
http://svn.apache.org/viewvc/isis/site/trunk/content/intro/tutorials/apacheconeu-2014.md?rev=1640504&r1=1640503&r2=1640504&view=diff
==============================================================================
--- isis/site/trunk/content/intro/tutorials/apacheconeu-2014.md (original)
+++ isis/site/trunk/content/intro/tutorials/apacheconeu-2014.md Wed Nov 19
08:51:11 2014
@@ -455,8 +455,20 @@ Finally, note that the layout of contrib
* use `.layout.json` to position as required
+
+
## Decoupling using the Event Bus
+Another way in which Apache Isis helps you keep your application nicely
modularized is through its event bus. Each action invocation, or property
modification, can be used to generate a succession of events that allows
subscribers to veto the interaction (the see it/use it/do it rules) or, if the
action is allowed, to perform work prior to the execution of the action or
after the execution of the action.
+
+Under the covers Isis uses the [Guava event
bus](https://code.google.com/p/guava-libraries/wiki/EventBusExplained) and
subscribers (always domain services) subscribe by writing methods annotated
with `@com.google.common.eventbus.Subscribe` annotation.
+
+By default the events generated are `ActionInteractionEvent.Default` (for
actions) and `PropertyInteractionEvent.Default` (for properties). Subclasses
of these can be specified using the
[@ActionInteraction](http://isis.apache.org/reference/recognized-annotations/ActionInteraction.html)
or
[@PropertyInteraction](http://isis.apache.org/reference/recognized-annotations/PropertyInteraction.html).
+
+
+Using the guidance in [these docs]():
+
+* write a domain service subscriber to
TODO
Modified: isis/site/trunk/content/reference/services/event-bus-service.md
URL:
http://svn.apache.org/viewvc/isis/site/trunk/content/reference/services/event-bus-service.md?rev=1640504&r1=1640503&r2=1640504&view=diff
==============================================================================
--- isis/site/trunk/content/reference/services/event-bus-service.md (original)
+++ isis/site/trunk/content/reference/services/event-bus-service.md Wed Nov 19
08:51:11 2014
@@ -56,16 +56,53 @@ Meanwhile, in the `BookRepository` domai
This design allows the `libraryMember` module to be decoupled from the `book`
module.
-### Self Registration
+## Registering for Events
-A good practice for domain services is to self-register when the
`EventBusService` is injected into it:
+#### 1.8.0-SNAPSHOT
- private EventBusService eventBusService;
- public void injectEventBusService(final EventBusService eventBusService) {
- this.eventBusService = eventBusService;
- eventBusService.register(this);
+Register for events in the `@PostConstruct` lifecycle method (and unregister
in `@PreDestroy`):
+
+ @DomainService
+ public class MySubscribingDomainService {
+
+ ...
+
+ @Programmatic
+ @PostConstruct
+ public void postConstruct() {
+ eventBusService.register(this);
+ }
+ @Programmatic
+ @PreDestroy
+ public void preDestroy() {
+ eventBusService.unregister(this);
+ }
+
+ @javax.inject.Inject
+ private EventBusService eventBusService;
}
+This works for both application-scoped and request-scoped (`@RequestScoped`)
domain services.
+
+
+#### 1.7.0 and before
+
+Register for events when the `EventBusService` is injected into it:
+
+ @DomainService
+ public class MySubscribingDomainService {
+
+ ...
+
+ private EventBusService eventBusService;
+ public void injectEventBusService(final EventBusService
eventBusService) {
+ this.eventBusService = eventBusService;
+ eventBusService.register(this);
+ }
+
+ }
+
+
### `@PostsPropertyChangedEvent`
