hi, let me add something...
I also experience Out of Memory exceptions.
My situation is this: I have a master-xml file (docbook) which includes 10 other docbook files using XInclude.
When I have all files open the oxygen process already eats about 180MB of RAM, which seems quite a lot. The XML istelf is not huge, all files together take 89kB space on harddisk.
When I in this situation try to start to transform it to PDF, I happen to get these exceptions. Solution is of course to close all open files, restart oxygenxml and only open the mainfile (in which case oxygenxml takes 70MB only). Then the transformation runs.
I have 512MB of RAM and oxygenxml really pushes the limits here
. (Together with Browser - Firefox also eats 60MB nowadays - IM software - Mail client, Thunderbird ...)
So, in the end... having that experience with 89kB of XML...
...maybe you could rethink, why the application needs so much extra RAM for every open file. And why it needs so much RAM in the first place. It doesn't seem so overly complex, so maybe there is a little waste here and there ...
Using Oxygen inside eclipse makes the situation even worse, because Eclipse already eats much RAM and CPU power itself, so I get Out of Memory Exceptions far more early using Eclipse than with Oxygen running in standalone mode.
Another symptom of the RAM hunger is the fact that windows pages unused applications to harddisk, to have more RAM for applications in use. Meaning: if I minimize oxygenxml and forget about it for a while, then it will take ages to load it again, because windows has to reload so many pages from harddisk to memory at once.
Yes, "buy more RAM" will help. I know. Maybe later.
Granted: with just one or two opened files, all runs quite smooth.