code: @Override
      public boolean evaluate() throws QueryEvaluationException {
          try {
              sync();
              return getMarkLogicClient().sendBooleanQuery(getQueryString(), getBindings(), getIncludeInferred(),getBaseURI());
          }catch (RepositoryException e) {
              throw new QueryEvaluationException(e.getMessage(), e);
          }catch (MalformedQueryException e) {
              throw new QueryEvaluationException(e.getMessage(), e);
          }catch (IOException e) {
              throw new QueryEvaluationException(e.getMessage(), e);
          }catch(FailedRequestException e){
              throw new QueryEvaluationException(e.getMessage(), e);
          }
      }
docs: evaluate boolean query
  
  @return boolean
  @throws QueryEvaluationException