code: public Filter convert(Criterion criterionDto, List<AttributeDescriptor> schema) {
  		FilterContext fc = new FilterContext();
  		fc.setSchema(schema);
  		criterionDto.accept(this, fc);
  		try {
  			log.debug("Filter converted : " + ECQL.toCQL(fc.getFilter()));
  		} catch (Exception e) {
  			// ignore
  		}
  		return fc.getFilter();
  	}
docs: Convert a criterion to a filter.
  
  @param criterionDto
  @param schema
  @return