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Process JMS messages in correct order and with good performance

A Java EE application gets data delivered by a JMS queue. Unfortunately, some of the messages which are delivered depend on each other, so they have to be processed in the correct order. As far i understand it, i can't rely on JMS here (or can i? i know that they will be sent in the correct order).
Additionally, it may be the case that there will be one kind of message that will be split by the provider of the messages, so that in some cases thousands of these messages will be sent to the application, all of them related to a specific entity. It would not be necessary to handle them one by one (which would be the easiest way, e.g. in a MDB) and i fear it will be a bad performance if i handle them this way, because i always have to save some information in the database, so i'd prefer to batch them in some way and handle them altogether in one transaction. But i don't know how to do this, since i didn't detect a way to batch messages while reading from a queue. I could get all messages out of a queue every second or so and process them, but then i don't know for sure if messages that depend on each other are already in there.
So i think i need some kind of buffering/caching or sth. like this between receiving and processing the JMS messages, but i don't see a good approach at the moment.
Any ideas how to handle this scenario?

Section 4.4.10 of the JMS spec states that:
JMS defines that messages sent by a session to a destination must be received
in the order in which they were sent (see Section 4.4.10.2 ”Order of Message
Sends,” for a few qualifications). This defines a partial ordering constraint on a
session’s input message stream
(The qualifications are mainly about QoS and non-persistent messages).
The spec continues:
JMS does not define order of message receipt across destinations or across a
destination’s messages sent from multiple sessions. This aspect of a session’s
input message stream order is timing-dependent. It is not under application
control.
So, relying on ordering in your JMS client really comes down to the session scope of your producer and the number of producers.
You could also consider grouping the related messages in a transaction to ensure atomicity of whatever operation you're performing.
Hope that helps a bit.
EDIT: I assume you know "related messages"/dependencies by using some sort of correlationID? I'm getting the idea that your problem is very similar to eg. TCP, so perhaps you could use the algorithms from that area to ensure ordered delivery of your messages?
Cheers,

A JMS Queue will definitely process them in the correct order. It is, after all, a Queue (and you can't cut in line).

JMS Client Session Usage

I'm attempting to utilize the .NET Kaazing client in order to interact with a JMS back-end via web sockets. I'm struggling to understand the correct usage of sessions. Initially, I had a single session shared across all threads, but I noticed that this was not supported:
A Session object is a single-threaded context for producing and consuming messages. Although it may allocate provider resources outside the Java virtual machine (JVM), it is considered a lightweight JMS object.
The reason I had a single session was just because I thought that would yield better performance. Since the documentation claimed sessions were lightweight, I had no hesitation switching my code over to use a session per "operation". By "operation" I mean either sending a single message, or subscribing to a queue/topic. In the former case, the session is short-lived and closed immediately after the message is sent. In the latter case, the session needs to live as long as the subscription is active.
When I tried creating multiple sessions I got an error:
System.NotSupportedException: Only one non-transacted session can be active at a time
Googling this error was fruitless, so I tried switching over to transacted sessions. But when attempting to create a consumer I get a different error:
System.NotSupportedException: This operation is not supported in transacted sessions
So it seems I'm stuck between a rock and a hard place. The only possible options I see are to share my session across threads or to have a single, non-transacted session used to create consumers, and multiple transacted sessions for everything else. Both these approaches seem a little against the grain to me.
Can anyone shed some light on the correct way for me to handle sessions in my client?

There are several ways to add concurrency to your application. You could use multiple Connections, but that is probably not desirable due to an increase in network overhead. Better would be to implement a simple mechanism for handling the concurrency in the Message Listener by dispatching Tasks or by delivering messages via ConcurrentQueues. Here are some choices for implementation strategy:
The Task based approach would use a TaskScheduler. In the MessageListener, a task would be scheduled to handle the work and return immediately. You might schedule a new Task per message, for instance. At this point, the MessageListener would return and the next message would be immediately available. This approach would be fine for low throughput applications - e.g. a few messages per second - but where you need concurrency perhaps because some messages may take a long time to process.
Another approach would be to use a data structure of messages for work pending (ConcurrentQueue). When the MessageListener is invoked, each Message would be added to the ConcurrentQueue and return immediately. Then a separate set of threads/tasks can pull the messages from that ConcurrectQueue using an appropriate strategy for your application. This would work for a higher performance application.
A variation of this approach would be to have a ConcurrentQueue for each Thread processing inbound messages. Here the MessageListener would not manage its own ConcurrentQueue, but instead it would deliver the messages to the ConcurrentQueue associated with each thread. For instance, if you have inbound messages representing stock feeds and also news feeds, one thread (or set of threads) could process the stock feed messages, and another could process inbound news items separately.
Note that if you are using JMS Queues, each message will be acknowledged implicitly when your MessageListener returns. This may or may not be the behavior you want for your application.
For higher performance applications, you should consider approaches 2 and 3.

How to remove messages from a topic

I am trying to write an Application that uses the JMS publish subscribe model. However I have run into a setback, I want to be able to have the publisher delete messages from the topic. The usecase is that I have durable subscribers, the active ones will get the messages (since it's more or less instantly) , but if there are inactive ones and the publisher decides the message is wrong, I want to have him able to delete the message so that the subscribers won't receive it anymore once they become active.
Problem is, I don't know how/if this can be done.
For a provider I settled on glassfish's implementation, but if other alternatives offer this functionality, I can switch.
Thank you.

JMS is a form of asynchronous messaging and as such the publishers and subscribers are decoupled by design. This means that there is no mechanism to do what you are asking. For subscribers who are active at time of publication, they will consume the message with no chance of receiving the delete message in time to act on it. If a subscriber is offline then they will but async messages are supposed to be atomic. If you proceed with design of other respondent's answer (create a delete message and require reconnecting consumers to read the entire queue looking for delete messages), then you will create a situation in which the behavior of the system differs based on whether or not a subscriber was online or not at the time a specific message/delete combination was was published. There is also a race condition in which the subscriber completes reading of the retained messages just before the publisher sends out the delete message. This means you must put significant logic into subscribers to reconcile these conditions and even more to reconcile the race condition.
The accepted method of doing this is what are called "compensating transactions." In any system where the producer and consumer do not share a single unit of work or share common state (such as using the same DB to store state) then backing out or correcting a previous transaction requires a second transaction that reverses the first. The consumer must of course be able to apply the compensating transaction correctly. When this pattern is used the result is that all subscribers exhibit the same behavior regardless of whether the messages are consumed in real time or in a batch after the consumer has restarted.
Note that a compensating transaction differs from a "delete message." The delete message as proposed in the other respondent's answer is a form of command and control that affects the message stream itself. On the other hand, compensating transactions affect the state of the system through transactional updates of the system state.
As a general rule, you never want to manage state of the system by manipulating the message stream with command and control functions. This is fragile, susceptible to attack and very hard to audit or debug. Instead, design the system to deliver every message subject to its quality of service constraints and to process all messages. Handle state changes (including reversing a prior action) entirely in the application.
As an example, in banking where transactions trigger secondary effects such as overdraft fees, a common procedure is to "memo post" the transactions during the day, then sort and apply them in a batch after the bank has closed. This allows a mistake to be reconciled before it causes overdraft fees. More recently, the transactions are applied in real time but the triggers are withheld until the day's books close and this achieves the same result.

JMS API does not allow removing messages from any destination (either queue or topic). Although I believe that specific JMX providers provide their own proprietary tools to manage their state for example using JMX. Try to check it out for your JMS provider but be careful: even if you find solution it will not be portable between different JMS providers.
One legal way to "remove" message is using its time-to-live:
publish(Topic topic, Message message, int deliveryMode, int priority, long timeToLive). Probably it is good enough for you.
If it is not applicable for your application, solve the problem on application level. For example attach unique ID to each message and publish special "delete" message with higher priority that will be a kind of command to delete "real" message with the same ID.

You have have the producer send a delete message and the consumer needs to read all messages before starting to process them.

Would a JMS Topic suffice in this situation? Or should I look elsewhere?

There is one controlling entity and several 'worker' entities. The controlling entity requests certain data from the worker entities, which they will fetch and return in their own manner.
Since the controlling entity can agnostic about the worker entities (and the working entities can be added/removed at any point), putting a JMS provider in between them sounds like a good idea. That's the assumption at least.
Since it is an one-to-many relation (controller -> workers), a JMS Topic would be the right solution. But, since the controlling entity is depending on the return values of the workers, request/reply functionality would be nice as well (somewhere, I read about the TopicRequester but I cannot seem to find a working example). Request/reply is typical Queue functionality.
As an attempt to use topics in a request/reply sort-of-way, I created two JMS topis: request and response. The controller publishes to the request topic and is subscribed to the response topic. Every worker is subscribed to the request topic and publishes to the response topic. To match requests and responses the controller will subscribe for each request to the response topic with a filter (using a session id as the value). The messages workers publish to the response topic have the session id associated with them.
Now this does not feel like a solution (rather it uses JMS as a hammer and treats the problem (and some more) as a nail). Is JMS in this situation a solution at all? Or are there other solutions I'm overlooking?

Your approach sort of makes sense to me. I think a messaging system could work. I think using topics are wrong. Take a look at the wiki page for Enterprise Service Bus. It's a little more complicated than you need, but the basic idea for your use case, is that you have a worker that is capable of reading from one queue, doing some processing and adding the processed data back to another queue.
The problem with a topic is that all workers will get the message at the same time and they will all work on it independently. It sounds like you only want one worker at a time working on each request. I think you have it as a topic so different types of workers can also listen to the same queue and only respond to certain requests. For that, you are better off just creating a new queue for each type of work. You could potentially have them in pairs, so you have a work_a_request queue and work_a_response queue. Or if your controller is capable of figuring out the type of response from the data, they can all write to a single response queue.
If you haven't chosen an Message Queue vendor yet, I would recommend RabbitMQ as it's easy to set-up, easy to add new queues (especially dynamically) and has really good spring support (although most major messaging systems have spring support and you may not even be using spring).
I'm also not sure what you are accomplishing the filters. If you ensure the messages to the workers contain all the information needed to do the work and the response messages back contain all the information your controller needs to finish the processing, I don't think you need them.

I would simply use two JMS queues.
The first one is the one that all of the requests go on. The workers will listen to the queue, and process them in their own time, in their own way.
Once complete, they will put bundle the request with the response and put that on another queue for the final process to handle. This way there's no need for the the submitting process to retain the requests, they just follow along with the entire procedure. A final process will listen to the second queue, and handle the request/response pairs appropriately.
If there's no need for the message to be reliable, or if there's no need for the actual processes to span JVMs or machines, then this can all be done with a single process and standard java threading (such as BlockingQueues and ExecutorServices).
If there's a need to accumulate related responses, then you'll need to capture whatever grouping data is necessary and have the Queue 2 listening process accumulate results. Or you can persist the results in a database.
For example, if you know your working set has five elements, you can queue up the requests with that information (1 of 5, 2 of 5, etc.). As each one finishes, the final process can update the database, counting elements. When it sees all of the pieces have been completed (in any order), it marks the result as complete. Later you would have some audit process scan for incomplete jobs that have not finished within some time (perhaps one of the messages erred out), so you can handle them better. Or the original processors can write the request to a separate "this one went bad" queue for mitigation and resubmission.
If you use JMS with transaction, if one of the processors fails, the transaction will roll back and the message will be retained on the queue for processing by one of the surviving processors, so that's another advantage of JMS.
The trick with this kind of processing is to try and push the state with message, or externalize it and send references to the state, thus making each component effectively stateless. This aids scaling and reliability since any component can fail (besides catastrophic JMS failure, naturally), and just pick up where you left off when you get the problem resolved an get them restarted.
If you're in a request/response mode (such as a servlet needing to respond), you can use Servlet 3.0 Async servlets to easily put things on hold, or you can put a local object on a internal map, keyed with the something such as the Session ID, then you Object.wait() in that key. Then, your Queue 2 listener will get the response, finalize the processing, and then use the Session ID (sent with message and retained through out the pipeline) to look up
the object that you're waiting on, then it can simply Object.notify() it to tell the servlet to continue.
Yes, this sticks a thread in the servlet container while waiting, that's why the new async stuff is better, but you work with the hand you're dealt. You can also add a timeout to the Object.wait(), if it times out, the processing took to long so you can gracefully alert the client.
This basically frees you from filters and such, and reply queues, etc. It's pretty simple to set it all up.

Well actual answer should depend upon whether your worker entities are external parties, physical located outside network, time expected for worker entity to finish their work etc..but problem you are trying to solve is one-to-many communication...u added jms protocol in your system just because you want all entities to be able to talk in jms protocol or asynchronous is reason...former reason does not make sense...if it is latter reason, you can choose other communication protocol like one-way web service call.
You can use latest java concurrent APIs to create multi-threaded asynchronous one-way web service call to different worker entities...

Is MQ publish/subscribe domain-specific interface generally faster than point-to-point?

I'm working on the existing application that uses transport layer with point-to-point MQ communication.
For each of the given list of accounts we need to retrieve some information.
Currently we have something like this to communicate with MQ:
responseObject getInfo(requestObject){
code to send message to MQ
code to retrieve message from MQ
}
As you can see we wait until it finishes completely before proceeding to the next account.
Due to performance issues we need to rework it.
There are 2 possible scenarios that I can think off at the moment.
1) Within an application to create a bunch of threads that would execute transport adapter for each account. Then get data from each task. I prefer this method, but some of the team members argue that transport layer is a better place for such change and we should place extra load on MQ instead of our application.
2) Rework transport layer to use publish/subscribe model.
Ideally I want something like this:
void send (requestObject){
code to send message to MQ
}
responseObject receive()
{
code to retrieve message from MQ
}
Then I will just send requests in the loop, and later retrieve data in the loop. The idea is that while first request is being processed by the back end system we don't have to wait for the response, but instead send next request.
My question, is it going to be a lot faster than current sequential retrieval?

The question title frames this as a choice between P2P and pub/sub but the question body frames it as a choice between threaded and pipelined processing. These are two completely different things.
Either code snippet provided could just as easily use P2P or pub/sub to put and get messages. The decision should not be based on speed but rather whether the interface in question requires a single message to be delivered to multiple receivers. If the answer is no then you probably want to stick with point-to-point, regardless of your application's threading model.
And, incidentally, the answer to the question posed in the title is "no." When you use the point-to-point model your messages resolve immediately to a destination or transmit queue and WebSphere MQ routes them from there. With pub/sub your message is handed off to an internal broker process that resolves zero to many possible destinations. Only after this step does the published message get put on a queue where, for the remainder of it's journey, it then is handled like any other point-to-point message. Although pub/sub is not normally noticeably slower than point-to-point the code path is longer and therefore, all other things being equal, it will add a bit more latency.
The other part of the question is about parallelism. You proposed either spinning up many threads or breaking the app up so that requests and replies are handled separately. A third option is to have multiple application instances running. You can combine any or all of these in your design. For example, you can spin up multiple request threads and multiple reply threads and then have application instances processing against multiple queue managers.
The key to this question is whether the messages have affinity to each other, to order dependencies or to the application instance or thread which created them. For example, if I am responding to an HTTP request with a request/reply then the thread attached to the HTTP session probably needs to be the one to receive the reply. But if the reply is truly asynchronous and all I need to do is update a database with the response data then having separate request and reply threads is helpful.
In either case, the ability to dynamically spin up or down the number of instances is helpful in managing peak workloads. If this is accomplished with threading alone then your performance scalability is bound to the upper limit of a single server. If this is accomplished by spinning up new application instances on the same or different server/QMgr then you get both scalability and workload balancing.
Please see the following article for more thoughts on these subjects: Mission:Messaging: Migration, failover, and scaling in a WebSphere MQ cluster
Also, go to the WebSphere MQ SupportPacs page and look for the Performance SupportPac for your platform and WMQ version. These are the ones with names beginning with MP**. These will show you the performance characteristics as the number of connected application instances varies.

It doesn't sound like you're thinking about this the right way. Regardless of the model you use (point-to-point or publish/subscribe), if your performance is bounded by a slow back-end system, neither will help speed up the process. If, however, you could theoretically issue more than one request at a time against the back-end system and expect to see a speed up, then you still don't really care if you do point-to-point or publish/subscribe. What you really care about is synchronous vs. asynchronous.
Your current approach for retrieving the data is clearly synchronous: you send the request message, and wait for the corresponding response message. You could do your communication asynchronously if you simply sent all the request messages in a row (perhaps in a loop) in one method, and then had a separate method (preferably on a different thread) monitoring the incoming topic for responses. This would ensure that your code would no longer block on individual requests. (This roughly corresponds to option 2, though without pub/sub.)
I think option 1 could get pretty unwieldly, depending on how many requests you actually have to make, though it, too, could be implemented without switching to a pub/sub channel.

The reworked approach will use fewer threads. Whether that makes the application faster depends on whether the overhead of managing a lot of threads is currently slowing you down. If you have fewer than 1000 threads (this is a very, very rough order-of-magnitude estimate!), i would guess it probably isn't. If you have more than that, it might well be.