@Override
    public void execute(FunctionContext context) {
      String dsClassName = (String) context.getArguments();
      try {
        Class aClass = Thread.currentThread().getContextClassLoader().loadClass(dsClassName);
        Constructor constructor = aClass.getConstructor();
        context.getResultSender().lastResult(constructor.newInstance());
      } catch (Exception e) {
        throw new FunctionException(e);
      }
    }
Get the port that the standard dunit locator is listening on.
geode-core/src/upgradeTest/java/org/apache/geode/internal/cache/rollingupgrade/RollingUpgrade2DUnitTestBase.java