This chapter presented an overview of DWR features including JavaScript libraries (util.js, engine.js, and gi.js), security, and Reverse AJAX and on basic operational elements of how DWR works.

In addition to the topics discussed in this chapter, DWR has lots of other useful features that may or may not be relevant to developers. It depends on the application. Topics in this chapter are intended to be high-level overviews, but they will give you a good starting point to learn more from the DWR website ( and even from the DWR source code.

Very often, most developers do not need all the features of a technology when they start working on a project. After the project has been going on for some time, we may find out that the solution has matured to include most if not all features of the technology. But that is typically not the initial case and, besides, we have to start somewhere and it is practical to start taking small steps at a time...