code: public static int parseVersionSpec(String versionString) throws NumberFormatException {
          if (versionString == null)
              return 0;
          int dot = versionString.indexOf('.');
          int major, minor;
          if (dot > 0) {
              major = Integer.parseInt(versionString.substring(0, dot));
              minor = Integer.parseInt(versionString.substring(dot + 1));
          }
          else {
              major = Integer.parseInt(versionString);
              minor = 0;
          }
          return major * 1000 + minor;
      }
docs: single digit without decimal means a major version not minor