Prerequisites & Preliminaries

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Ideally, you would be a decent Java developer and have a good grasp of Web Service concepts and technologies. Throw in some familiarity with a Linux/*nix shell and you should sail through this Primer. Especially, if you have already skimmed through the Developer's Guide to get a rough idea of what gCF can do for you. The viewpoint and style of the Guide are different from this Primer's, and we believe they complement each other well to help you out.

If you don't call yourself a decent Java developer...then by all means keep reading, just be prepared for a very steep learning curve. If instead you are not much versed in Web Service concepts and technologies, then this brief summary from the Globus guys is a good starting point, as it is Sotomayor's second chapter of his much-read GT4 Tutorial. And remember, this is the kind of topic for which Google remains your best friend (just stay away from the standard specs for a while longer). As to your familiarity with a shell, no worries, you will need only a modicum to begin with. Best of luck.

Coming to the machine, no point in going ahead before having installed and configured gCore, not only for administration but also for building (ANT) and development (JDK5). In particular, double-check that your administrator has set for you the environment variable GLOBUS_LOCATION to the gCore installation directory by your administrator. If not so, define it now.

Unless you are insanely devoted to your shell, you will also want a good Java IDE at hand. The Primer's uses the good old Eclipse for all the examples. And unless you are playing, you will need some client for at least committing and checking out your code to and from a Version Control System, preferably a good plugin for your IDE (e.g. Subversion for Eclipse).

IDE and shell are your two main development tools. In particular, the overall plan is to:

  • use the Java IDE for authoring code and configuration, as well as for versioning code;
  • use the shell for building and deploying code, as well as for all the other administrative tasks.

The idea is now to align them with some initial configuration:

  • Open a fresh Eclipse Workspace and make sure to associate it with a suitable version of the Java 5 compiler. This is the workspace for your gCube services.
  • Define an environment variable BUILD_LOCATION and point it precisely to the workspace location. This is the location from which you will build your gCube services.

As a result, you code is right below where you build it, no need to jump around.

Now you are ready to start.