How we'll use our service

How are we actually going to persuade our client netlet to use our new service? Well, access to any service is via a warrant, so we'll have to create a new warrant.

The last warrant we used, in Chapter , was downloaded from the Jtrix.org site. That was a warrant for the hello world service provided by Jtrix.org. If we give the same client netlet a different warrant it can use a different service.

What's the key information we need to put in the warrant? A warrant tells the node how to bind the access point netlet. That means it contains either (a) a netlet descriptor, describing the access point netlet, or (b) a reference to where the netlet descriptor can be downloaded from. (See Figure .) We'll use option (a). We'll embed a descriptor of the access point netlet inside the warrant.

So the client netlet will use this new warrant. It will present it to the node via the node's bindService() method, the node will look in the warrant to see how to bind the access point netlet, it will see the netlet descriptor embedded in there and it will use that descriptor to create the access point netlet.

The netlet descriptor must also contain all the JARs for its codebase, or else URLs saying where they can be found.

Now let's have a look at the netlet code...