Ant

So far we have been giving commands like javac, jar from command line to build our program. Clearly this won't scale for a typical project that has hundreds of files, external libraries, etc.

We need a build tool - Enter Ant.

With Ant, we can do a declarative build. In a file called build.xml, we can specify what needs to be built and how - then Ant can do that. It makes things easier to manage.