Taariq San

Good job, congrats.
Now I don't feel so bad anymore, I scored 71% exactly.

I recently did the LVC course and it's mostly videos, you go at your own pace at the times that suit you.

Hi Simon

Great looking book and with perfect timing for me, I look forward to reading it.

Do you touch on hardware sizing at all?

I don't see anything on testing, with Camel the testing support is great but it takes a little bit of learning,
the book Camel in Action has a chapter on testing which illustrates this well.
So I wondered if this is a consideration with Spring Integration too, or if it's so simple you don't mention it.
Or maybe it's sprinkled around the different chapters.

Thanks, looking forward to reading the book, and to trying it out.

Good stuff, thanks to you both.

I've been reading the docs and fiddling with some code and just want to check I understand correctly.
At this point I don't yet see how it's going to work, so a little patience please.

Hang on, I just found that Spring provides a ThreadPoolTaskExecutor, so I'll use that to return the Future to the calling client, which will obviously hang on the get() until it's response is available.

The business of getting that response after it's been put into the collection for processing brings me back to the wait and notify scenario
to get the response out of the outgoing collection, so please ignore the previous post and let me know if you have something in mind to replace that wait/notify on the outgoing collection.

I'm looking around in the locks package, so I can perhaps have an exclusive write lock and a lot of concurrent reads until the response is there?

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Hi

I'm still in the scribbling phase, haven't implemented any of the following yet so
if there's a better way of doing things please advise.

We'll have a cluster of JVMs receiving JMS messages, the sender expects a response, eventually.
Halfway through the message processing we'll get a distributed lock from a cache to be able to do some
batch processing of these messages, and send the message off to the batch processing code.
So in effect there's only ever one JVM sending out batches at any given time.

The response will not be immediate, but eventually as I said the JMS consumer should send
back a response based on whatever happens in that batching process.

Now the title says "Wait, notify alternative", because one of the solutions I thought of is
to have the batching process expose a public method that returns the result, but keeps the
calling thread waiting until some other process is done with the batch that includes the caller's message,
then obviously returns the result. It could sync on some object and wait for a notify,
then check if it's message has been processed.

I'm looking through the concurrency package and other sources to see if there's something efficient to help out,
as this is expected to scale to deal with at least a million such messages per day and that batching process
is always going to be a singleton due to the nature of the business.

Any hints are welcome.
Taariq

Hi

At the moment we have a swing client that connects via rmi and we cannot change the client at all,
what we want to do though is change the way the transactions work, we can everything
except the swing client.
I've looked at Spring MVC, and others like it, and while the pattern implies you can yank one
out and plug in another it's just not the way it works, or seems to work. I suppose this is why there's Spring RPC
for rich clients.

Now maybe I don't need a framework for what I'm after, so let me get to the point.
I want the transaction flow and the config to slap together some components.
The view could be the swing client in most cases but also our website which will expose some transactions
to the coderanch.
We could also have web services simply supply the service class everything it needs to
do it's work without any client populating various objects as it goes along.

Should I look again at Spring Web Flow or something similar?

Hi Dhanji

I see a number of questions on working with existing code but I wonder if your book
touches on this or provides further reading around that or if indeed such coverage is needed at all.

We have millions of lines of source we have no intention of changing in one go even if we
wanted to, but we'd love to go forward using DI and rework old code here and there as we go along.

Is the book everything I need?

Best wishes with the book

Hi

Are you aware of any books in progress?

Nope.

And with this pattern it takes 2 to tango, you need one to monitor changes and another to notify of changes.
You register your object as a listener, like the ActionListener type classes. Then you're notified of changes.
If this other component you speak of cannot be changed to pass you a different object, one that 'has a' list,
then I'm not sure how you'll approach this.

Thank you Dennis, yes that answers my question.

Hi Dennis

Does it work at all or is it fixed to a single port?

Thanks,
Taariq

Also look at JIBX, if performance is a serious consideration.

Hi

I'm fiddling with PDFs and iText to insert images and barcode images into PDF forms.

I'm just wondering if one uses a placeholder for the images when creating the form or
is that space simply left blank and then set the absolute location when populating with iText?

I just thought that maybe the image can be set as we do
for text fields with setField and PdfStamper.

Thanks
Taariq