Launch/management basics

Although the launch process and the management process are different, both are handled at the same console, so we use the phrases ``launcher'' and ``console'' interchangably.

To launch an application we need:

• A launch descriptor. This is a bit like a netlet descriptor but has a bit more information in it.
• A warrant for a hosting service (that's where the application will initially live, and whose resources it will consume);
• Probably a warrant for a SAS. The SAS warrant is so that anyone using the application can bind it (and hence its netlets). However, if the application wants to run its own binding then a SAS warrant isn't necessary. For example, we might be launching our own SAS service. Or we might be happy for all our warrants and netlet descriptors to contain embedded JARs, rather than containing JAR references. The significant downside of this, of course, is that they will all be several megabytes long.

The document Programming with Jtrix: The Beatrix application framework has more on launching applications and launch descriptors, so we won't cover them any more here.

To manage an application we need a warrant, and the application needs to support console commands.