红帽全球峰会175.6. 预定义的过滤器
从 Camel 版本 2.13.0 开始，JGroups 组件附带了预定义的过滤器工厂类，名为 JGroupsFilters。
如果您希望只使用发送到集群的协调器的更改通知（并忽略这些发送到"slave"节点）的更改通知，请使用 JGroupsFilters.dropNonCoordinatorViews （） 过滤器。当您希望单个 Camel 节点成为集群中的主节点时，此过滤器特别有用，因为当给定节点成为集群的协调器时，传递此过滤器的消息会通知您。以下片段演示了如何仅收集 master 节点接收的消息。
import static org.apache.camel.component.jgroups.JGroupsFilters.dropNonCoordinatorViews;
...
from("jgroups:clusterName?enableViewMessages=true").
filter(dropNonCoordinatorViews()).
to("seda:masterNodeEventsQueue");
import static org.apache.camel.component.jgroups.JGroupsFilters.dropNonCoordinatorViews;
...
from("jgroups:clusterName?enableViewMessages=true").
filter(dropNonCoordinatorViews()).
to("seda:masterNodeEventsQueue");
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