Flex has gotten popular lately because of its rich GUI capabilities. It also comes in handy with HTTPService and Web Service components connecting to back-end servers to fetch and update data. But using this mechanism to talk to the back-end server requires formulating a unique service object from the Flex side, making a request, and getting back data from the back-end either in XML or plain text format. The response data then has to be parsed and fed to the Flex objects to update the UI. For small to medium-size Flex projects it's a viable solution, but for enterprise projects with thousands of external service calls it will get quite repetitive and could result in a lot of unmanageable, buggy code.
The approach discussed here provides a more intuitive solution to generate ActionScript classes on the Flex side that are direct counterparts of the enterprise object classes in the back-end server. This way the Flex environment just becomes an extension of the back-end server and the Flex UI gets access to back-end objects. The infrastructure to make remote calls to the back-end server is taken care of by the framework that marshals objects to the back-end to make service calls and un-marshals the results to ActionScript objects transparently so the developer can concentrate just on the UI logic.
