docs: @SuppressWarnings ( "unchecked" )
      @Override
      public <T extends Address> T unwrap ( Class<T> type ) {
          if ( this.addr instanceof Address ) {
              return ( (Address) this.addr ).unwrap(type);
          }
          else if ( this.getClass().isAssignableFrom(type) ) {
              return (T) this;
          }
          return null;
      }