code: public static String getVersion() {
          if (version != null)
              return version;
          try (InputStream stream = CDK.class.getResourceAsStream(RESOURCE_LOCATION)) {
              if (stream == null) {
                  // load from JAR (as packaged with maven)
                  version = CDK.class.getPackage().getImplementationVersion();
              }
              Properties props = new Properties();
              props.load(stream);
              version = props.getProperty("version");
              return version;
          } catch (IOException exception) {
              // there is no back up
              logger.error("Error while loading the build.props file: ", exception.getMessage());
              logger.debug(exception);
          }
          return null;
      }
docs: Returns the version of this CDK library.
  
  @return The library version, or null if it could not be found