Build and Install a Plugin - Learn to Program with Minecraft Plugins - page 30

In the Java world, you have to place all these files in specific places for
this all to work. We made a directory structure like that earlier, all ready
for your version of the HelloWorld plugin. I've also got a complete plugin all
set up for you in the HelloWorld directory in the code for this topic, which
you downloaded to Desktop/code/HelloWorld .
So in Desktop/code/HelloWorld , you'll find a directory tree for the source code,
under src . You'll also see a bin directory where the compiled class files are
created, and a dist directory where the class file and configuration files are
packed together into a jar file. When you're ready to share your plugin
with others, you'll give them the jar.
HelloWorld is one development directory. You'll probably have one of these
for each plugin you develop, each with its own src , bin , dist , and so on.
Then over in your server directory at Desktop/server , you have the Minecraft
server files, including CanaryMod.jar , which contains all the bits you need to
run the game, as well as the parts we're using to develop code in the
Minecraft worlds.