build.xml

<?xml version="1.0" encoding="UTF-8"?>
<project name="Minecraft" default="default" basedir=".">
  <taskdef name="bundleapp" classname="com.oracle.appbundler.AppBundlerTask" classpath="appbundler-1.0.jar" />
  <target name="bundle-Minecraft">
    <bundleapp outputdirectory="." name="Minecraft" displayname="Minecraft" identifier="net.minecraft" mainclassname="net.minecraft.bootstrap.Bootstrap">
      <classpath file="Minecraft.jar" />
    </bundleapp>
  </target>
</project>