Ant Script for Validating file exists otherwise terminate

Ant Script for Validating file exists otherwise terminate

<target name="Validating Files" description="Validating Files" >
  <echo message="Checking Compiled Files "/>
  <fail message="Files are missing.">
    <condition>
        <not>
            <resourcecount count="2">
                <fileset id="fs" dir="../ViewController/public_html" includes="one.txt,two.txt"/>
            </resourcecount>
        </not>
    </condition>
  </fail>
</target>