ExecutorService is a good to use class, but it have a little problem in domino
It's nice when company politic allow you to fix it like this
If you are not allowed to do it, than you got a little trouble. Fortunately Java is creator friendly language, so you could do ExecutorService himself.
I did NotesExecutorService on the base of next articles:
Modification NotesExecutorService for run multiple thread agents you could find following link How to run Domino Java agents in Multi threads
NotesExecutorService itself under the cut
Example of using NotesExecutorService