define its own format and semantics. This was generally a properties format.
            <p>Since Maven 3.2.4, the type for this field has been changed to Properties to match the de-facto
            format.
            <p>Each toolchain defines its own properties names and semantics.
          </description>
        </field>
        <field>
          <name>configuration</name>

        // make sure repeated entries are skipped
        Mirror mirrorA3 = newMirror("a", "a", "http://a3");

        Mirror mirrorB = newMirror("b", "b", "http://b");
        Mirror mirrorC = newMirror("c", "d,e", "http://de");
        Mirror mirrorC2 = newMirror("c", "*", "http://wildcard");
        Mirror mirrorC3 = newMirror("c", "e,f", "http://ef");