Thanks Rob. Josh
On 6/14/08, Rob Davies <[EMAIL PROTECTED]> wrote: > > > On 14 Jun 2008, at 01:50, Joshua Smith wrote: > > All- >> >> I'm reading a number of references on JMS written some time between 2001 >> and >> now. The challenge that comes with that is knowing which things are still >> true today and which things were describing the state of affairs at that >> time. I found the following paragraph in the O'reilly Java Message Service >> (First Edition) book written in 2001 on p. 32. Can anyone confirm that >> this >> is still an accurate description of JMS? >> >> >> "The Chat application ((which is what they use for their JMS example in >> the >> book)) uses a separate session for the publisher and subscriber, >> pubSession >> and subSession, respectively. This is due to a threading restriction >> imposed >> by JMS. ***According to the JMS specification, a session may not be >> operated >> on my more than one thread at a time.*** In our example, two threads of >> control are active: the default main thread of the Chat application and >> the >> thread that invokes the onMessage() handler. The thread that invokes the >> onMessage() handler is owned by the JMS provider. Since the invocation of >> the onMessage() handler is asynchronous, it could be called while the main >> thread is publishing a message in the writeMessage() method. If both the >> publisher and subscriber had been created by the same session, the two >> threads could operate on these methods at the same time; in effect, they >> could operate on the same TopicSession - a condition that is prohibited." >> (emphasis mine) >> >> >> Thanks, >> Joshua Smith >> > > > Hi Joshua, > > I used to have a copy of that book somewhere! > Yep - its still an accurate description of JMS > > > > > cheers, > > Rob > > http://open.iona.com/products/enterprise-activemq > http://rajdavies.blogspot.com/ > > > > >
