code: public List list(Class clazz, String key, Object value)
      {
          QueryCriteria criteria = new QueryCriteria(key, QueryCriteriaOperator.EQUAL, value);
          Query query = new Query(clazz, criteria);
          try {
              return persistenceManager.executeLazyQuery(query);
          } catch (InitializationException ignore){}
          catch (Exception e) {
              e.printStackTrace();
          }
  
          return null;
      }
docs: Execute query with criteria of key = key
  
  @param clazz Entity to query
  @param key Attribute to predicate upon
  @param value Attribute key to predicate upon
  @return List of entities that match the criteria