ckget.xml

<project>
  <macrodef name="ckget">
    <attribute name="url" />
    <attribute name="dir" />
    <attribute name="checksum" />
    <attribute name="algorithm" default="md5" />
    <attribute name="skipexisting" default="true" />
    <sequential>
      <local name="filename" />
      <basename property="filename" file="@{url}" />
      <get dest="@{dir}" skipexisting="@{skipexisting}">
        <url url="@{url}"/>
      </get>
      <local name="checksum.matches"/>
      <local name="checksum.matches.fail"/>
      <checksum file="@{dir}/${filename}" algorithm="@{algorithm}"
                property="@{checksum}" verifyproperty="checksum.matches" />
      <condition property="checksum.matches.ok">
        <istrue value="${checksum.matches}" />
      </condition>
      <fail unless="checksum.matches.ok">Checksum failed downloading @{url}</fail>
    </sequential>
  </macrodef>
</project>