<project> 

        <target name="clean"> 
                <delete dir="build"/> 
        </target> 

        <target name="compile"> 
                <mkdir dir="build/classes"/> 
                <javac srcdir="src" destdir="build/classes"/> 
        </target> 

        <target name="jar"> 
                <mkdir dir="build/jar"/> 
                <jar destfile="build/jar/HelloWorld.jar" basedir="build/classes"> 
                        <manifest> 
                                <attribute name="Main-Class" value="demo.HelloWorld"/> 
                        </manifest> 
                </jar> 
        </target> 

        <target name="run"> 
                <java jar="build/jar/HelloWorld.jar" fork="true"/> 
        </target> 

</project>

<project name="antdemo" basedir="." default="deploy"> 

  <!-- Project settings --> 
  <property name="project.distname" value="antdemo" /> 
  <property name="src.dir" value="src" /> 
  <property name="lib.dir" value="lib" /> 

  <!-- Local system paths --> 
  <property name="build.dir" value="build" /> 
  <property name="classes.dir" value="${build.dir}/classes" /> 
  <property name="jar.dir" value="${build.dir}/jars" /> 

  <property name="main-class" value="demo.HelloWorld" /> 

  <!-- outer jar lib --> 
  <path id="classpath"> 
    <fileset dir="${lib.dir}" includes="**/*.jar" /> 
  </path> 

  <target name="clean"> 
    <delete dir="${build.dir}" /> 
  </target> 

  <target name="compile"> 
    <mkdir dir="${classes.dir}" /> 
    <!-- In javac, we should improt the chasspathref which needed. --> 
    <javac srcdir="${src.dir}" destdir="${classes.dir}"  classpathref="classpath" />     
     <copy todir="${classes.dir}"> 
                        <fileset dir="${src.dir}" excludes="**/*.java"/> 
                </copy> 
     
  </target> 

  <!-- Create jar --> 
  <target name="jar" depends="compile"> 
    <mkdir dir="${jar.dir}" /> 
    <jar destfile="${jar.dir}/${ant.project.name}.jar" basedir="${classes.dir}"> 
      <manifest> 
        <attribute name="Main-Class" value="${main-class}" /> 
      </manifest> 
    </jar> 
  </target> 

  <target name="run" depends="jar"> 
    <!-- <java jar="${jar.dir}/${ant.project.name}.jar" fork="true"/>--> 
    <!-- set classpath --> 
    <java fork="true" classname="${main-class}"> 
      <classpath> 
        <path refid="classpath" /> 
        <path location="${jar.dir}/${ant.project.name}.jar" /> 
      </classpath> 
    </java> 
  </target> 

  <target name="clean-build" depends="clean,jar" /> 

  <target name="deploy" depends="clean,run" /> 


</project>