Getting started with Ant.


Do you know what Ant is?
========================

If you don't know what ant is,
read "backgroundAboutAnt.txt" first.


Acknowledgements
================

  Much of the material here is adapted from:

  http://blog.ideoplex.com/software/java/antTutorial2.html

Getting ready to use Ant on strauss
===================================

Before we can start using Ant, we have to make sure
we can find the "ant" command.

I've installed Ant in the following directory on strauss:

   /www/htdocs/CIS/software/dist/apache-ant-1.6.5/

So on strauss, you'd need to add the following to your .localenv
file to make Ant work for you:

 if -d /www/htdocs/CIS/software/dist/apache-ant-1.6.5 then
  setenv ANT_HOME /www/htdocs/CIS/software/dist/apache-ant-1.6.5 
  setenv NEWPATH $ANT_HOME/bin:$NEWPATH
 endif

See my notes in the file topics/java/compilingOnStrauss for 
hints about making the .localenv file work on strauss.

For bash, use (according to http://ant.apache.org/manual/index.html)
something like the following.

 export ANT_HOME=/www/htdocs/CIS/software/dist/apache-ant-1.6.5
 export JAVA_HOME=/usr/jdk1.5
 export PATH=${PATH}:${ANT_HOME}/bin


Creating your first ant build file
==================================

We'll work with the file HelloWorld.java.

We'll set up a file called "build.xml", which is the
default name for an ant "build file".

<project default="compile">
  <target name="compile">
    <javac srcdir="." />
  </target>
</project>


Note that we have no class file in our directory before
we type "ant".  Afterwards, we do!

> ls
HelloWorld.java            backgroundAboutAnt.txt     build.xml                  gettingStartedWithAnt.txt
> ant 
Buildfile: build.xml

compile:
    [javac] Compiling 1 source file

BUILD SUCCESSFUL
Total time: 4 seconds
> ls 
HelloWorld.class           backgroundAboutAnt.txt     gettingStartedWithAnt.txt
HelloWorld.java            build.xml

Then, if we type ant again, note that magically, "nothing happens".
Ant is smart enough to realize that we don't need to recompile,
because we haven't changed anything.

> ant
Buildfile: build.xml

compile:

BUILD SUCCESSFUL
Total time: 2 seconds
> 

Then, we make a change to HelloWorld.java, and re do the ant command:

> emacs HelloWorld.java
> ant
Buildfile: build.xml

compile:
    [javac] Compiling 1 source file

BUILD SUCCESSFUL
Total time: 5 seconds
> 

And, we magically recompile.

Now, let's make it more interesting by creating a jar file too.
(Read up on jar files in topics/java/deployment/jarFiles if you
don't know about jar files yet!)


New contents of build.xml:

<project default="compile">
  <target name="compile">
    <javac srcdir="." />
  </target>

  <target name="jar" depends="compile">
    <jar destfile="hello.jar"
         basedir="."
         includes="**/*.class"
         />
  </target>
</project>



References and further reading
==============================


References:
	http://blog.ideoplex.com/software/java/antTutorial2.html

For more Ant tutorials from the same source:
	http://blog.ideoplex.com/software/java/


 A good overview of how to use Ant in practice:
    http://ant.apache.org/ant_in_anger.html