Articles : Java Networking :

Writing Servlets

Overview

In the last article, we discussed how to install the Java Server Web Development Kit (JSWDK) which comes with its own Servlet-Enabled web server. Now that the JSWDK is installed, we can focus on writing our first servlets.

The first servlets discussed here are relatively simple. However, as the Networking Java tutorial series continues, we will build upon the servlets we write here. They will be used to provide examples of how Java Servlets interoperate with other servers and clients. Servlets are a great place to start talking about Network programming in Java for two reasons: simplicity and flexibility.

Servlets are the simplest way to write server-side Java because Servlet implementations already provide you with the guts of a Java server. Specifically, Java Servlet implementations have the capability to retrieve and send data as well as accept connections in a multithreaded fashion.

Servlets are also flexible. Initially our focus will be to use servlets to produce HTML documents. However, servlets can also produce arbitrary and complex data streams that can be interpreted by Java applets, applications, and other network clients in a variety of ways.

The first servlet presented here is the equivalent of a "Hello, World!" servlet. We will follow with discussing issues of passing data to and from the servlet as well as maintaining state. Then we will build on these simple servlets in subsequent articles on network programming with other servers using APIs such as Java DataBase Connectivity (JDBC).

NEXT

Gunther Birznieks contributes to JavaBoutique's Web/Networking column. Gunther currently works for Barclays Capital in London, one of the leading global investment banks in Europe and has previously worked as a senior computer scientist in the Human Genome Project. Gunther is also known for writing several books on Web Programming (Perl, CGI, Java) as well as for co-creating Extropia with Selena Sol. Extropia is one of the best known public domain web programming archives Email: gunther@extropia.com.

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