A question regarding Synchronous, Pub-Sub non-durable model

Question

          Scenario:
          Non-durable, publish-subscribe, syncronous model.
          Publisher1 and Publisher2 both post messages to a Topic at the same time. How to
          design the non durable Subscribers that would be able to obtain both these messages
          in the same thread?
          e.g. if i in my program I create 2 subscribers, with selectors configured for the
          2 different messages...
          program start
          1. create sub1 using selector1 for topic1
          2. create sub2 using selector2 for topic1
          3. sub1.receive(timeout)
          4. sub2.receive(timeout)
          5. further processing using both the obtained messages
          6. program end.
          In the above case, if messages arrive at the same time in the topic, only sub1 will
          be able to get the message, as sub2 won't be active at that time.
          Is there anyway to acheive this considering Synchronous, Pub-Sub non-durable model
          is to be used?
          Many thanks...
          

Answer 1

          Thanks for the response.
          Is a subscriber active the moment it is created?
          e.g. objSub=tsession.createSubscriber(topic,strMessSelector,true);
          or it is said to be active when we call
          objSub.receive() (in case of synchronous subscriber)
          "Shean-Guang Chang" <[email protected]> wrote:
          >I don't know the details of the design. You can use a single subscriber
          >without a selector and then do two receive to get both message.
          >If you have to use selector so sub1 can only select message from pub1 and
          >sub2 can only select message from pub2 then you need sub3 without a
          >selector and sub3 will do blocking receive first and then once the sub3
          >receives a message you can use sub1 and sub2 to do receiveNoWait.
          >
          >e.g.
          >while (true) {
          > if (sub3.receive() ! = null) { // have message in the topic
          > if (sub1.receiveNoWait() != null) { // got message from pub1
          > do something
          > }
          > if (sub2.receiveNoWait() != null) {// got message from pub2
          > do something
          > }
          > }
          >}
          >
          >"vinay s" <[email protected]> wrote in message
          >news:[email protected]...
          >>
          >> Scenario:
          >> Non-durable, publish-subscribe, syncronous model.
          >> Publisher1 and Publisher2 both post messages to a Topic at the same time.
          >How to
          >> design the non durable Subscribers that would be able to obtain both these
          >messages
          >> in the same thread?
          >> e.g. if i in my program I create 2 subscribers, with selectors configured
          >for the
          >> 2 different messages...
          >>
          >> program start
          >> 1. create sub1 using selector1 for topic1
          >> 2. create sub2 using selector2 for topic1
          >> 3. sub1.receive(timeout)
          >> 4. sub2.receive(timeout)
          >> 5. further processing using both the obtained messages
          >> 6. program end.
          >>
          >> In the above case, if messages arrive at the same time in the topic, only
          >sub1 will
          >> be able to get the message, as sub2 won't be active at that time.
          >>
          >> Is there anyway to acheive this considering Synchronous, Pub-Sub
          >non-durable model
          >> is to be used?
          >>
          >> Many thanks...
          >
          >