/**
  * @see
  *     org.happyfaces.services.base.IService#list(org.happyfaces.jsf.datatable.PaginationConfiguration)
  */
 @Override
 public List<T> list(final PaginationConfiguration config) {
   Predicate predicate = getPredicate(config);
   Pageable pageable =
       new PageRequest(
           config.getFirstRow() / config.getNumberOfRows(),
           config.getNumberOfRows(),
           config.getSortField() != null
               ? new Sort(new Sort.Order(config.getSortDirection(), config.getSortField()))
               : null);
   return ((GenericRepository<T, Long>) getRepository())
       .findAll(predicate, pageable, config.getFetchFields())
       .getContent();
 }
  /**
   * Creates a Predicate from list of BooleanExpression predicates which represents all search
   * filters.
   *
   * @param config PaginationConfiguration data holding object
   * @return query to filter entities according pagination configuration data.
   */
  @SuppressWarnings({"rawtypes", "unchecked"})
  protected Predicate getPredicate(PaginationConfiguration config) {

    PathBuilder<T> entityPath = new PathBuilder(entityClass, getAliasName(entityClass));
    BooleanExpression predicate = null;

    Map<String, Object> filters = config.getFilters();
    if (filters != null) {
      // first we process nonstandard filters
      List<String> filtersToRemove = processNonStandardFilters(filters, entityPath);
      filters = removeUsedFilters(filtersToRemove, filters);
      if (!filters.isEmpty()) {
        for (Map.Entry<String, Object> entry : filters.entrySet()) {
          String key = entry.getKey();
          Object filter = entry.getValue();
          if (filter != null) {

            // if ranged search (from - to fields)
            if (key.contains("fromRange-")) {
              // CHECKSTYLE:OFF
              String parsedKey = key.substring(10);
              // CHECKSTYLE:ON
              if (filter instanceof Number) {
                NumberPath path = createNumberPath(entityPath, parsedKey, filter);
                predicate = and(predicate, path.goe((Number) filter));
              } else if (filter instanceof Date) {
                DatePath path = entityPath.getDate(parsedKey, Date.class);
                predicate = and(predicate, path.goe((Date) filter));
              }
            } else if (key.contains("toRange-")) {
              // CHECKSTYLE:OFF
              String parsedKey = key.substring(8);
              // CHECKSTYLE:ON
              if (filter instanceof Number) {
                NumberPath path = createNumberPath(entityPath, parsedKey, filter);
                predicate = and(predicate, path.loe((Number) filter));
              } else if (filter instanceof Date) {
                DatePath path = entityPath.getDate(parsedKey, Date.class);
                predicate = and(predicate, path.loe((Date) filter));
              }
            } else if (key.contains("list-")) {
              // CHECKSTYLE:OFF
              // if searching elements from list
              String parsedKey = key.substring(5);
              // CHECKSTYLE:ON
              ListPath path = entityPath.getList(parsedKey, filter.getClass());
              predicate = and(predicate, path.contains(filter));
            } else { // if not ranged search
              if (filter instanceof String) {
                StringPath path = entityPath.getString(key);
                String filterString = (String) filter;
                predicate = and(predicate, path.startsWithIgnoreCase(filterString));
              } else if (filter instanceof Date) {
                DatePath path = entityPath.getDate(key, Date.class);
                predicate = and(predicate, path.eq(filter));
              } else if (filter instanceof Number) {
                NumberPath path = createNumberPath(entityPath, key, filter);
                predicate = and(predicate, path.eq(filter));
              } else if (filter instanceof Boolean) {
                BooleanPath path = entityPath.getBoolean(key);
                predicate = and(predicate, path.eq((Boolean) filter));
              } else if (filter instanceof Enum) {
                EnumPath path = entityPath.getEnum(key, Enum.class);
                predicate = and(predicate, path.eq(filter));
              } else if (BaseEntity.class.isAssignableFrom(filter.getClass())) {
                PathBuilder path = entityPath.get(key);
                predicate = and(predicate, path.eq(filter));
              }
            }
          }
        }
      }
    }
    return predicate;
  }