Guidelines to Convert Ant task to Gradle

Hi Fellows,

I don’t have any experience in Ant.
But I know a little bit about Gradle, and the buildscript.

I am wondering, how to install tools from the build script using Gradle.
So, i do some research about it and find that the Gitlist build script have done it.
Link : https://github.com/klaussilveira/gitlist/blob/master/build.xml
From the buildscript, I know that the first step is to install composer, and the composer will install the tools (phploc, phpmd, pdepend, etc).

But, the problem is the build script written in Ant.
I want to make it in Gradle, without import it directly by using "ant.importBuild 'build.xml"
Do some of you have any suggestion to me, about how I can convert the build Script?

Thanks