examples/ant/midlets.xml

<!-- This Ant build file illustrates how to process J2ME midlets.
     Usage: ant -f midlets.xml -->

<project name="Midlets" default="obfuscate" basedir="../..">

<target name="obfuscate">
  <taskdef resource="proguard/ant/task.properties"
           classpath="lib/proguard.jar" />

  <proguard microedition="on"
            overloadaggressively="on"
            repackageclasses=""
            allowaccessmodification="on"
            printseeds="on">

            <!-- On Windows, you can't use mixed case class names,
                 for the sake of the preverify tool.
            usemixedcaseclassnames="false">
            -->

    <!-- Specify the input jars, output jars, and library jars. -->

    <injar  file="in.jar" />
    <outjar file="out.jar" />

    <libraryjar file="/usr/local/java/wtk2.1/lib/midpapi20.jar" />
    <libraryjar file="/usr/local/java/wtk2.1/lib/cldcapi11.jar" />

    <!-- Preserve all public midlets. -->

    <keep access="public" extends="javax.microedition.midlet.MIDlet" />

    <!-- Preserve all native method names and the names of their classes. -->

    <keepclasseswithmembernames>
      <method access="native" />
    </keepclasseswithmembernames>
    
    <!-- Your application may contain more items that need to be preserved;
         typically classes that are dynamically created using Class.forName -->

   </proguard>
</target>

</project>