Java Enterprise Best Practices

Pregenerate Content Offline and Cache Like Mad

Pregeneration and caching of content can be key to providing your site visitors with a quality experience. With the right pregeneration and caching, web pages pop up rather than drag, and loads are reduced—sometimes dramatically—on the client, server, and network. In this section I’ll provide advice for how best to pregenerate content and cache at the client, at the proxy, and at the server. By the end of this section you’ll feel compelled to generate new content during request handling only in worst-case scenarios.

There’s no need to dynamically regenerate content that doesn’t change between requests. Yet such regeneration happens all the time because servlets and JSPs provide an easy way to template a site by pulling in headers, footers, and other content at runtime. Now this might sound like strange guidance in a chapter on servlets, but in many of these situations servlets aren’t the best choice. It’s better to “build” the content offline and serve it as static content. When the content changes, you can build the content again. Pull the content together once it is offline rather than during every request.

Take, for example, an online magazine, newspaper, or weblog ('blog). How do the pros handle templatization without burdening the server? By pregenerating the content. Articles added to a site are written and submitted in a standard format (often XML-based) which, when run through a build process, produces a comprehensive update ...