Servlets ... servlets ... servlets. That's all you hear--well, in this book, at any rate. I hope this book will give you a good grounding, and that after reading it, you'll get a feel for where servlets can best be used. By no means does this book cover all the uses of servlets; such a book could never exist. Servlets are a lightweight/heavyweight solution to the problem of server-side processing.
Java has proven to be a serious contender in the field of commercial software. It has delivered on nearly all of its highly over-hyped claims, failing on only a few bothersome issues that have been cleared up as the Java Development Kit (JDK) version numbers creep on.
Look at what Java has done for the browser. No other plug-in or extension has grown as quickly. If a Java applet could do this for the client, just think what the servlet can do for the server.
It's up to you now as our frontline troops in the server wars. You are now in possession of a technology that allows you to get on with what you know best and leave all the administrative hassles of server dependency behind.
Servlets give you the power to develop a sophisticated, platform-independent solution. This is the most scalable software you could ever build. With the Java servlet combination, you can easily upgrade any of your components without redeveloping any classes.
With the new generation of servlet Application Program Interfaces (API), server farms are no longer a problem. As far as your servlet is concerned, it is running on a single server with all the resources at hand. But in reality, the picture could be different. Your server could be part of a larger server pool, sharing resources and load balancing between all the machines.
But you as the servlet developer need not worry about such things. If you stick to the API, you shouldn't have any problems in the future as the success of your creation grows.
Servlets are the solution the server has been looking for for a very long time.