In the previous chapter, we learnt about providing the Web Services interface to an application where ADempiere is a downstream application for it. In an enterprise environment, there is another possibility, as well. There, ADempiere will be an upstream application interfacing with other downstream applications. In this chapter, I have taken a popular shopping cart application—Joomla! VirtueMart—as the downstream application. Even though ADempiere has its own web store, for different practical reasons, an enterprise may opt for other shopping cart applications, such as VirtueMart, Magento, osCommerce, and so on and would like to have ADempiere use them as their web store rather than the built-in one.

Coming to the integration mechanism, there are various options available. One of the major points that we'll have to keep in perspective while choosing an integration technology/framework is that VirtueMart is implemented in PHP whereas ADempiere is in Java. We are running our...