long story how the question came up but I got royally schooled as I have never written a Java app without an IDE. I was asked questions on ANT and the build.xml file! I was like "WTF are they talking about" then was asked the question "have you coded in java before?" and then I realised I know nothing about the true basics of Java so need a good source of info about it.
I have had a look but not really sure what I should Google to find what I am looking for.
This will however not teach you anything about Ant. Ant is a very widely used tool by Apache for automating the build process of projects without needing an IDE.
If the response to your answer "I don't know what Ant is", was "Have you actually ever programmed in Java before?!", then that's a bit of an unfair response. Not knowing about Ant doesn't mean you don't know anything about Java - although almost every professional Java programmer will most likely have encountered Ant sometime.
I agree with Jesper, the relation to Ant and Java is not relevant. A nice (but obnoxious) answer could have been "no, I always use Maven to build my Java project so that I can get a proper version and dependency handling without having to handle it myself". ;)
I know most about Build, but I do not know C... ;)