code: public void clearTenant(String tenantId) {
          String index = getIndex(tenantId);
  
          synchronized (knownIndices) {
              IndicesAdminClient indices = client.admin().indices();
  
              boolean indexExists = indices.prepareExists(index)
                      .execute()
                      .actionGet()
                      .isExists();
  
              if (indexExists) {
                  indices.prepareDelete(index)
                          .execute()
                          .actionGet();
              }
  
              knownIndices.remove(index);
          }
      }
docs: Removes all data associated with tenant.
  
  @param tenantId index