<project name="MyProject" default="dist" basedir="."> <description> simple example build file </description> <!-- set global properties for this build --> <property name="src" location="src"/> <property name="build" location="build"/> <property name="dist" location="dist"/> <target name="init"> <!-- Create the time stamp --> <tstamp/> <!-- Create the build directory structure used by compile --> <mkdir dir="${build}"/> </target> <target name="compile" depends="init" description="compile the source " > <!-- Compile the java code from ${src} into ${build} --> <javac srcdir="${src}" destdir="${build}"/> </target> <target name="dist" depends="compile" description="generate the distribution" > <!-- Create the distribution directory --> <mkdir dir="${dist}/lib"/> <!-- Put everything in ${build} into the MyProject-${DSTAMP}.jar file --> <jar jarfile="${dist}/lib/MyProject-${DSTAMP}.jar" basedir="${build}"/> </target> <target name="clean" description="clean up" > <!-- Delete the ${build} and ${dist} directory trees --> <delete dir="${build}"/> <delete dir="${dist}"/> </target> </project>Notice that we are declaring properties outside any target. The <property>, <typedef> and <taskdef> tasks are special in that they can be declared outside any target. When you do this they are evaluated before any targets are executed. No other tasks can be declared outside targets. We have given some targets descriptions; this causes the projecthelp invocation option to list them as public targets with the descriptions; the other target is internal and not listed.
Finally, for this target to work the source in the src subdirectory should be stored in a directory tree which matches the package names. Check the <javac> task for details.