• An optional HTML page that users can refer to for support.
• Some optional Java classes that will take advantage of the runtime services supplied by
the JNLP Client. In our example, we used a simple installer class that takes charge of the
whole first-time installation process.
A Procedure for JNLP Deployment
Let's recap the main steps necessary to deploy an application using the JNLP technology. We
will take advantage of Chapter 4 for general advice. To deploy an application using JNLP, the
deployment engineer (see Chapter 2, “An Abstract Model for Deployment”) should perform
the following activities:
1. Produce a complete catalog of all needed application resources.
2. Organize such application resources in deployment units, called modules .
3. Implement the obtained modules in JNLP constructs that will form the JNLP files of our
4. Create the proper JNLP resources (creating JAR files, writing the application homepage,
and so on).
5. Deploy the JNLP files and JNLP resources with the proper file hierarchy on the
Deployment Server. (This corresponds to the Producer To Distributor Publication Step in
the abstract model of Chapter 2).
Note that this possible procedure may be modified as needed or made iterative (that is, alter-
nating a first simpler JNLP file, trying it out, and then refining it again) especially if it is the
first time you use this technology or if your application is quite complex.
Let's examine these steps in detail.
List All Application Resources
Usually, the resources employed in an application fall into one of the following categories.
•Other files (images, properties files, and so on)
• Third-party libraries (help support, JDBC drivers, and so on)
• Optional packages (previously known as extensions )
• The required J2SE JRE version
•Other resources (native libraries, special executables, and so on)
Map Application Resources in Modules
This step consists of decomposing the resources mentioned above into a coherent set of mod-
ules . We discussed this issue in Chapter 4.