code: public CMAArray<CMASnapshot> fetchAllSnapshots(CMAContentType contentType) {
      assertNotNull(contentType, "contentType");
  
      final String contentTypeId = getResourceIdOrThrow(contentType, "contentType");
      final String spaceId = getSpaceIdOrThrow(contentType, "contentType");
      final String environmentId = contentType.getEnvironmentId();
  
      return service.fetchAllSnapshots(spaceId, environmentId, contentTypeId).blockingFirst();
    }
docs: Fetch all snapshots of this content type.
  
  @param contentType the contentType whose snapshots to be returned.
  @return an array of snapshots.
  @throws IllegalArgumentException if contentType is null.
  @throws IllegalArgumentException if contentType's id is null.
  @throws IllegalArgumentException if contentType's space id is null.