the example is the Ant in Action book:
<?xml version="1.0" encoding="gb2312"?>
<project name="fistbuild" default="execute">
<description>Compiles ant runs a simple program</description>
<target name="init">
<mkdir dir="build/classes"/>
<mkdir dir="dist"/>
</target>
<target name="compile" depends="init"
description="Compiles the source code">
<javac srcdir="src" destdir="build/classes"/>
</target>
<target name="archive" depends="compile"
description="Creates the jar file">
<jar destfile="dist/project.jar" basedir="build/classes"/>
</target>
<target name="clean" depends="init"
description="Removes the temporary directories used">
<delete dir="build"/>
<delete dir="dist"/>
</target>
<target name="run" depends="compile"
description="Runs the program">
<java
classname="test.Main"
classpath="build/classes">
<arg value="a"/>
<arg value="b"/>
<arg file="."/>
</java>
</target>
</project>