JDBC (SQL) not working in thread

Question

I was surprised by a strange (bug?)
I had two programs that were implementing the Java Serial Port API, each interfaced to a specific instrument. I was asked to combine the two programs into one, run it on one workstation, and run it as a service. This is on an W2K machine and they want it to work even if no one is logged in.
Well, I started each class as a serial port listener and a runnable, thinking it might be best for each listener to have its own thread. That runs just fine. But, one of the instruments sends a lot of data, so once I had a buffer full of stuff to parse and upload (to Oracle), is started another processing thread to handle the data, and let the parent thread get back to listening to the serial port.
Well, I parsed the data just fine, but after I created the connection, created a statement, and then tried to execute a line of SQL, it just stopped, no exceptions, but no results. I keep a log of what is going on, and it looks like the thread just dies.
So, for experimenation, I changed the parent threads back to plain classes and created the instances of them, still leaving the processing piece as a thread. (The only draw back to this is that I cannot transmit from both instruments at the same time.) Well, the SQL worked fine, so I am wondering if there is a problem with the JDBC and threads, or inner threads?
Anyone have any suggestions?
Thanks,

Answer 1

As I understand it, your code does not work only when you run it as a service. Although I may well not understand it (for example I don't know what you think an "inner" thread is, and I don't understand your distinction between "class" and "thread", since everything runs in some thread or other in Java).
Is this correct? Have you managed to get the original (single instrument) code running as a service? My guess is that there's nothing wrong with Java, but there is some issue with running it as a service.