code: public static double parseDouble (@Nullable final Object aObject, final double dDefault)
    {
      if (aObject == null)
        return dDefault;
      if (aObject instanceof Number)
        return ((Number) aObject).doubleValue ();
      return parseDouble (aObject.toString (), dDefault);
    }
docs: Parse the given {@link Object} as double. Note: both the locale independent
  form of a double can be parsed here (e.g. 4.523) as well as a localized
  form using the comma as the decimal separator (e.g. the German 4,523).
  
  @param aObject
  The object to parse. May be <code>null</code>.
  @param dDefault
  The default value to be returned if the passed object could not be
  converted to a valid value.
  @return The default value if the object does not represent a valid value.