code: public void calcFillSettings(String field, Map<String,Object> attributes) {
          String capitalizedFieldName = StringUtils.capitalize(field);
          String methodName = "doFill" + capitalizedFieldName + "Items";
          Method method = ReflectionUtils.getPublicMethodNamed(getClass(), methodName);
          if(method==null)
              throw new IllegalStateException(String.format("%s doesn't have the %s method for filling a drop-down list", getClass(), methodName));
  
          // build query parameter line by figuring out what should be submitted
          List<String> depends = buildFillDependencies(method, new ArrayList<>());
  
          if (!depends.isEmpty())
              attributes.put("fillDependsOn",Util.join(depends," "));
          attributes.put("fillUrl", String.format("%s/%s/fill%sItems", getCurrentDescriptorByNameUrl(), getDescriptorUrl(), capitalizedFieldName));
      }
docs: Computes the list of other form fields that the given field depends on, via the doFillXyzItems method,
  and sets that as the 'fillDependsOn' attribute. Also computes the URL of the doFillXyzItems and
  sets that as the 'fillUrl' attribute.