| PackageDescription | Apache Ant is a Java-based build tool. In theory, it is kind of like
Make, but without Make's wrinkles.
Why another build tool when there is already make, gnumake, nmake, jam,
and others? Because all those tools have limitations that Ant's
original author could not live with when developing software across
multiple platforms. Make-like tools are inherently shell-based--they
evaluate a set of dependencies then execute commands, not unlike what
you would issue in a shell. This means that you can easily extend these
tools by using or writing any program for the OS that you are working
on. However, this also means that you limit yourself to the OS, or at
least the OS type, such as Unix, that you are working on.
Makefiles are inherently evil as well. Anybody who has worked on them
for any time has run into the dreaded tab problem. "Is my command not
executing because I have a space in front of my tab???" said the
original author of Ant way too many times. Tools like Jam took care of
this to a great degree, but still have yet another format to use and
remember.
Ant is different. Instead of a model where it is extended with
shell-based commands, Ant is extended using Java classes. Instead of
writing shell commands, the configuration files are XML-based, calling
out a target tree where various tasks are executed. Each task is run by
an object that implements a particular task interface.
Granted, this removes some of the expressive power that is inherent by
being able to construct a shell command such as `find . -name foo -exec
rm {}`, but it gives you the ability to be cross-platform--to work
anywhere and everywhere. If you really need to execute a shell command,
Ant has an <exec> task that allows different commands to be executed
based on the OS used. |