docs: public DocumentRevisionTree add(InternalDocumentRevision documentRevision) {
          Misc.checkArgument(!sequenceMap.containsKey(documentRevision.getSequence()),
                  "The revision must not be added to the tree before.");
  
          if(documentNumericId == -1l && docId == null){
              documentNumericId = documentRevision.getInternalNumericId();
              docId = documentRevision.getId();
          } else if (!(documentRevision.getInternalNumericId() == documentNumericId ||
                  documentRevision.getId().equals(docId))) {
              //document is not part of the same three though exception
              throw new IllegalArgumentException("Document revision is not part of the same tree");
  
          }
  
          if(documentRevision.getParent() <= 0) {
              addRootDBObject(documentRevision);
          } else {
              addNode(documentRevision);
          }
          return this;
      }