code: private void initializeBigMapField(StorageEngine storageEngine, Field field) {
          field.setAccessible(true);
  
          try {
              BigMap a = field.getAnnotation(BigMap.class);
              field.set(this, storageEngine.getBigMap(field.getName(), a.keyClass(), a.valueClass(), a.mapType(), a.storageHint(), a.concurrent(), false));
          }
          catch (IllegalArgumentException | IllegalAccessException ex) {
              throw new RuntimeException(ex);
          }
      }
docs: Initializes a field which is marked as BigMap.
  
  @param storageEngine
  @param field