Java application servers and multitier development are hot topics at the moment, for good reasons. Client-side Java may or may not someday supplant the native Windows, Unix, and Macintosh GUIs, but server-side Java is well suited to the delivery of network services into the standard HTML/JavaScript client. In the middle-tier environment, the servlet architecture makes it straightforward to build portable, reliable, and responsive services that export and use web APIs and manage complex object data.

For groupware developers, servlets are an essential item in a well-stocked toolkit. You can deploy them on high-end commercial platforms, but as we’ve seen in this chapter, you can also create simple groupware servlets using nothing but the JDK and a bit of imagination.