code: public LocalDocument insertLocalDocument(final String docId, final DocumentBody body) throws
              DocumentException {
          Misc.checkState(this.isOpen(), "Database is closed");
          CouchUtils.validateDocumentId(docId);
          Misc.checkNotNull(body, "Input document body");
          try {
              return get(queue.submit(new InsertLocalDocumentCallable(docId, body)));
          } catch (ExecutionException e) {
              logger.log(Level.SEVERE, "Failed to insert local document", e);
              throw new DocumentException("Cannot insert local document", e);
          }
      }
docs: <p>Inserts a local document with an ID and body. Replacing the current local document of the
  same ID if one is present. </p>
  
  <p>Local documents are not replicated between DocumentStores.</p>
  
  @param docId      The document ID for the document
  @param body       JSON body for the document
  @return {@code DocumentRevision} of the newly created document
  @throws DocumentException if there is an error inserting the local document into the database