code: private void validate() {
  
          if (host.isEmpty()) {
              throw new IllegalArgumentException("host cannot be null");
          }
          if (catalog == null) {
              throw new IllegalArgumentException("database cannot be null");
          }
          if (table == null) {
              throw new IllegalArgumentException("collection cannot be null");
          }
  
          concantHostPort();
      }
docs: validates connection parameters