Practical Internet Groupware

Chapter 10. Groupware Servlets

In Part I and Part II we saw how the core Internet client applications—mail, news, and web—can singly and in combination enable a group to create, share, catalog, and find documents that form the basis of collaborative work. Here in Part III, we’ve begun to explore ways to extend the core services, using the Web’s CGI and namespace APIs and the NNTP API to create customized groupware. We’ll do more of this in later chapters, because the core Internet services—and in particular, web servers—are amazingly versatile components. But conventional web servers are really just specialized file servers that have been outfitted with a mechanism—the CGI gateway—to launch external programs. In this chapter we’ll focus on an alternative mechanism that’s more naturally attuned to the delivery of network services. Java servlets present the same kinds of web APIs as do conventional CGI scripts. They’re inherently fast, reliable, lightweight, and threaded, and they can capably manage the kinds of complex data structures that groupware services typically involve. For all these reasons, servlets belong in every groupware developer’s toolkit.

We’ll look at two groupware servlets: Polls and GroupCal. Polls, which we saw briefly in Chapter 4, is a URL-driven survey tool that you can use to quantify the sense of a group regarding some question or issue. GroupCal is a shared bulletin board that presents free-form data in a calendar format. Writing these two servlets convinced ...