Java - Which accounting module is best to embed in my JAVA application?

I am developing a java application. I want to integrated some accounting module in my app. I don't want any feature-rich accounting module. I just want to maintain

• salaries
• expenses
• genera开发者_运维技巧ting invoices

So do you know any FREE OPEN SOURCE accounting module so that I can integrate it with my app.

Have a look at GNU i think it meets your description:

http://www.gnuaccounting.org/