Broker 10.5 | webMethods Broker Documentation | webMethods Broker Client Java API Programmer's Guide | Using Broker Clients | Broker Connection Descriptors | Sharing Client State | By-Publisher Event Ordering
By-Publisher Event Ordering
The Broker guarantees that events from a single publishing client cannot be processed out of order. This has important implications when several Broker clients are sharing the same event queue. The table below shows a client event queue containing events received from three different publishing clients; Broker client A, Broker client B, and Broker client C.
Publishing Client
Event Queue Position
BrokerClient A
BrokerClient B
BrokerClient A
BrokerClient C
BrokerClient B
BrokerClient C
Consider these steps:
1. BrokerClient X receives the event from queue position 1 without acknowledging the event.
2. BrokerClient Y receives the event from queue position 2 without acknowledging the event.
3. When BrokerClient Y then asks for another event, it is given the event from queue position 4 because the last event published by Client A has not yet been acknowledged. For more information on acknowledging events, see Using Sequence Numbers.