Unless you are working on improvements to the eclim installer, you shouldn't ever need to build it, but should the need arise here are the instructions for doing so.
To build the installer you first need a couple external tools installed:
sphinx: Sphinx is used to build the eclim documentation which is included in the installer.
Eclim also uses a custom sphinx theme which is included in eclim as a git submodule. So before you can build the installer you will need to initialize the submodule:
$ git submodule init
$ git submodule update
graphviz: The docs include a few uml diagrams which are generated using plantuml (included in the eclim source tree) which in turn requires graphviz.
formic: The eclim installer has been developed using the formic framework, and requires it to build the installer distributables. Formic doesn't currently have an official release, so you'll need to check out the source code:
$ git clone git://github.com/ervandew/formic.git
After checking out the code, you'll need to build the formic distribution:
$ cd formic
$ ant dist
Then extract the formic tar to the location of your choice
$ tar -zxvf build/dist/formic-0.2.0.tar.gz -C /location/of/your/choice
Once you have installed the above dependencies, you can then build the eclim installer with the following command.
$ ant -Dformic.home=/your/formic/install/dir dist
In lieu of supplying the formic home on the command line, you can instead put
it in a user.properties file at the eclim source root:
$ vim user.properties
formic.home=/your/formic/install/dir