Java Development Tools

Hi Gurus,
I have to develop an application in ADF, but the issue is there are very frequent changes in the application. How would i will structure the application. Is is possible to make some kind of library like jar or some kind of else. I want my application should be modularize. If i change in one module i don't want to deploy the whole application agian. I need just i replace only file and there you go. that's all. Like currently in forms application i just change only in one fmx file and it take effects all. I want my application should have different module, in which module a change and replace the file not want to deploy whole application for a single change like button caption.

Thanks,