60.9. Camel 事件到 CDI 事件
可从 Camel 2.17 开始
Camel 提供一组 管理事件 ,可订阅侦听 Camel 上下文、服务、路由和交换事件。Camel CDI 将这些 Camel 事件无缝转换为 CDI 事件,这些事件可以通过 CDI 监控器方法,例如:
void onContextStarting(@Observes CamelContextStartingEvent event) {
// Called before the default Camel context is about to start
}
void onContextStarting(@Observes CamelContextStartingEvent event) {
// Called before the default Camel context is about to start
}
从 Camel 2.18 开始,可以观察特定路由的事件(RouteAddedEvent、RouteStartedEvent、RouteStoppedEvent 和 RouteRemovedEvent)应该有一个显式定义,例如:
from("...").routeId("foo").to("...");
void onRouteStarted(@Observes @Named("foo") RouteStartedEvent event) {
// Called after the route "foo" has started
}
from("...").routeId("foo").to("...");
void onRouteStarted(@Observes @Named("foo") RouteStartedEvent event) {
// Called after the route "foo" has started
}
当 CDI 容器中存在多个 Camel 上下文时,Camel 上下文 belifiers (如 @ContextName )可用于优化观察器方法解析到特定 Camel 上下文,例如: http://docs.jboss.org/cdi/spec/1.2/cdi-spec.html#observer_resolution
同样,如果存在多个上下文,可以使用 @Default qualifier 观察 Camel 上下文的 Camel 事件,例如:
void onExchangeCompleted(@Observes @Default ExchangeCompletedEvent event) {
// Called after the exchange 'event.getExchange()' processing has completed
}
void onExchangeCompleted(@Observes @Default ExchangeCompletedEvent event) {
// Called after the exchange 'event.getExchange()' processing has completed
}
在该示例中,如果没有指定限定符,则会隐式假设 @Any qualifier,以便接收所有 Camel 上下文的对应事件。
请注意,仅在部署中检测到监听 Camel 事件的观察方法,并且每个 Camel 上下文中检测到对 Camel 事件的支持才会激活。