private String getConstraint() {
   StringBuilder buffer = new StringBuilder();
   buffer.append("Providers: type=");
   buffer.append(ProviderType.FOREMAN.name());
   String query = QueryHelper.getConstraint(getUriInfo(), null, modelType, false);
   if (StringUtils.isNotBlank(query)) {
     buffer.append(" AND (");
     buffer.append(query);
     buffer.append(")");
   }
   return buffer.toString();
 }
 protected List<Q> getBackendCollection(SearchType searchType) {
   return getBackendCollection(searchType, QueryHelper.getConstraint(getUriInfo(), "", modelType));
 }