Java Development Tools

Hi ,
what is the best structure for building complete adf applications .
for example if i hava a project of sales . i put the common model in one applications contanin the list of values also .
and one application for purchasing and another application for setup data and so on .
so i divide it in more than one applications .
but i face a problem to gather all these application in one main applications using jar files , as each application module will get a new connection to the database
and also how i will see the task flow in each application to deal with it in the main applications ?

i need help please .