To close this chapter, we look at a couple of advanced techniques you can use with the KVM. If your focus is on developing applications for mass market wireless devices, the techniques shown in this section will be of little relevance, because they require you to be able to build your own copy of the VM from its source code and ship it along with your application. This is an option that is likely to be open to you only if you are using the KVM in a specialist application of some kind or if you are working for a device vendor incorporating the KVM into a new product.
In order to build the KVM, you need to download a copy of the CLDC
reference implementation and acquire a suitable compiler and build
tools. The details of the build process and the development tools
with which it has been tested can be found in the KVM
Porting Guide, which is one of documents included with the
reference implementation. Since describing how to compile the VM is
beyond the scope of this book, the rest of this section assumes you
have set up an environment within which you can compile and link the
VM using the
Makefiles supplied by Sun.
In a J2SE
system, the core class libraries are stored in the file
rt.jar and are dynamically loaded and linked on
demand from the point at which the VM starts up. This has two
consequences, both of which are not ideal in the kind of
limited-resource environment toward which the KVM is targeted:
The process of loading a class ...