Ant to spin up background process for junit tests
<java classpath="${jar.dir}/foo.jar" classname="foo.Server" fork="true"  failonerror="true">
         <arg value="7777"/>
     </java>

spawn does not allow attributes related to input, output, error, result
spawn also does not allow timeout
finally, spawn is not compatible with a nested I/O <redirector>

<target name="junit" depends="build-jar">
     <mkdir dir="${report.dir}"/>

     <junit printsummary="yes">
         <classpath>
             <path refid="junitcp"/>
         </classpath>
         <formatter type="brief"/>
         <batchtest fork="yes" todir="${report.dir}">
             <fileset dir="${homeDir}" includes="foo/*Test.java"/>
         </batchtest>
     </junit>
 </target>