build.xml

<project name="net2" default="build">

    <property name="kotlin.lib" value="lib"/>

    <typedef resource="org/jetbrains/kotlin/ant/antlib.xml"
             classpath="${kotlin.lib}/kotlin-ant.jar"/>

    <path id="classpath">
        <fileset dir="${kotlin.lib}">
            <include name="**/*.jar" />
        </fileset>
    </path>

    <target name="build">
        <delete dir="classes" failonerror="false"/>
        <mkdir dir="classes"/>
        <javac destdir="classes" includeAntRuntime="false" srcdir="src">
            <withKotlin/>
            <classpath refid="classpath" />
        </javac>
        <jar destfile="net2-server.jar"
             manifest="src/ru/nsu/ccfit/pleshkov/net2/server/META-INF/MANIFEST.MF">
            <fileset dir="classes">
            </fileset>
            <zipgroupfileset dir="${kotlin.lib}" includes="*.jar" />
        </jar>
        <jar destfile="net2-client.jar"
             manifest="src/ru/nsu/ccfit/pleshkov/net2/client/META-INF/MANIFEST.MF">
            <fileset dir="classes">
            </fileset>
            <zipgroupfileset dir="${kotlin.lib}" includes="*.jar" />
        </jar>
    </target>
</project>