Sunday 29 July 2007

Why Ant?

Since I'm relatively new to the Java universe, I come with some preconceived ideas. One of them was that when you need to build something, you need to write some makefiles. So I never could understand why should the Java crowd need one another tool? Admittedly, make has got its quirks, but it is there, it's stable and it's understood. And the makefiles are human-readable! So I searched the internet for an answer. A typical statement would look like this:

Ant has been on the top of many a developer's list as the revolutionary tool that got them out of the world of make. For those of you not familiar with make, it'll be enough t say that it just isn't the best tool to use for building Java projects, since it isn't platform-independent and it isn't that easy to use.*
Not easy to use??? Come angain? What about Ant's XML-disease:
Ant ... uses an XML configuration file, the infamous build.xml. Ant has enjoyed heavy popularity with its many advantages, but it also has some drawbacks. The build.xml files can be extremely terse, and their use requires the developer to learn the syntax up front.*
...the disease of forcing humans to use a machine-oriented markup language to configure the build process! But the main gripe, as I understood it, was make's usage of tabs to demarcate the commands to be invoked for specific rules:
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.**
You kidding? I personally didn't have any problems with tabs, never ever. That cannot be the reason for one another tool! Only when I read this I understood:
Gnu make+Unix, windows and NMAKE, etc. While single-IDE or single-platform development worked in small, in-house projects, it didn't cut it for open source dev, where one person may have a solaris box with make on, but the other developer is on a windows system, another on a version of debian-unstable they built themselves. There's is/was not enough unity of infrastructure to stabilise on tools, so James Duncan Davidson had to write one. Ant. ***
Well, the real reason is the portability: the problem, which JVM solved for us. But as I see it, there is another side to this. Did you notice the phrase "the other developer ... on a windows system"? That's it: Microsoft is killing make, is killing the Unix legacy with Java's hands! Because there's no make installation on Windows, not because make isn't platform independent (it' written in C, you have only to recompile it). And because it's rm not del, and dir not ls. Microsoft couldn't kill Unix toolchain all alone, but ironically Java helped here a great deal by defining a new level of abstraction, which requires new tools. Ok, at last, the riddle is solved...

But wait, there's a moral in this story too! Strictly speaking even two morals. First: there's a lot of half-truths on the internet, and second: the truth isn't easily revealed, but it pays to search for it.

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* http://www.onjava.com/pub/a/onjava/2006/03/29/maven-2-0.html
** this I understood as a received wisdom coming right from the source: http://ant.apache.org/
*** http://www.1060.org/blogxter/entry?publicid=0E729BD9B8A06F372CC136D402810C82

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