Quick question on data structure used in JMS APIs

[kiran kulkarni]

Hi Guys,

I was just going through JMS APIs for implementing an application. But started to dig out on how JMS APIs are built. Specifically on what data structures those APIs use.
I assume they should using List internally for implementing Queue.

So, it would be great if anyone can help in resolving my doubt.

[Madhan Sundararajan Devaki]

Queuing is just one aspect of JMS. It also involves message transmission/reception and storage.

[kiran kulkarni]

Yes Madhan I agree on the features of JMS! But I am just curious to know what's behind the scene of JMS APIs... i.e internal data structure used for Queue. I am firm on LinkedList but want someone to confirm it.

[Madhan Sundararajan Devaki]

Most often, a database of some sort is used.

[kiran kulkarni]

But database or any external storage is outside the scope of JMS APIs. Here I am discussing about object enqueueing and dequeueing during runtime.

[Madhan Sundararajan Devaki]

Enqueue inserts a message into the DB used by the JMS Provider.

Dequeue selects-deletes-and-returns a message from the DB used by the JMS Provider.

[Tom Ellis]

I may be misunderstanding your question but the JMS spec/API is implemented by many different vendors/providers - are you attempting to implement the API yourself? It's probably best to get an open source implementation - you could take a look at Apache ActiveMQ.