build.xml

<project name="mlockall-agent" default="jar">
  <property name="agent.class" value="MLockAgent" />
  <property name="agent.jar" value="build/jar/${ant.project.name}.jar" />

  <!-- Give user a chance to override props without editing this file
      (and without typing -D each time) -->
  <property file="${basedir}/build.properties"/>
  <property file="${user.home}/${ant.project.name}.build.properties"/>
  <property file="${user.home}/build.properties"/>
  
  <!-- might be jna.jar, might be jna-3.2.7.jar ... roll with it -->
  <basename property="jna.jar.name" file="${jna.jar.path}" />

  <target name="-fail-unless-jna-property" unless="jna.jar.path">
    <!-- TODO: use ivy to fetch explicit version of JNA and put it in 
         build/jar for user to copy along with agent jar? 
    -->
    <fail>...

      Building this project requires that you explicitly set the
      property "jna.jar.path" to the JNA jar on your system.

      You can do this using "ant -Djna.jar.path=... compile"
      or by creating a build.properties file
      (or one of several other override files, see build.xml for details)
    </fail>
  </target>

  <target name="clean" description="Deletes build artifacts">
    <delete dir="build"/>
  </target>
  
  <target name="compile" description="Compiles java code"
          depends="-fail-unless-jna-property">
    <mkdir dir="build/classes"/>
    <javac srcdir="src" 
           destdir="build/classes"
           classpath="${jna.jar.path}"
           includeantruntime="false"
           debug="true"
           />
  </target>
  
  <target name="jar" description="Creates agent jar"
          depends="-fail-unless-jna-property,compile">
    <mkdir dir="build/jar"/>
    <jar destfile="${agent.jar}" 
         basedir="build/classes">
      <manifest>
        <!-- NOTE: when building classpaths nto the jar, include variants, 
             don't asume jars will never move 
             (Really wish "java -jar foo.jar" supported "-cp" 
             so this could all be external)
        -->

        <!-- setup the jar as an agent -->
        <attribute name="Agent-Class" value="${agent.class}"/>
        <attribute name="Premain-Class" value="${agent.class}"/>
        <attribute name="Boot-Class-Path" value="jna.jar ${jna.jar.name} ${jna.jar.path}"/>

        <!-- setup the jar for running as a demo -->
        <attribute name="Main-Class" value="${agent.class}"/>
        <attribute name="Class-Path" value="${jna.jar.path} ${jna.jar.name} jna.jar"/>

      </manifest>
    </jar>
  </target>
  
  <target name="run-demo" description="Runs the agent in demo mode">
    <java jar="${agent.jar}"
          fork="true"/>
  </target>

</project>