日期 2020.03.29
    问题 如何实现多条动态件筛选
    如何解决 segmentfault
    使用spring data jpa实现统一的多条件查询

    repository

    1. @Repository
    2. public interface UserRepository extends JpaRepository<User, Integer>, JpaSpecificationExecutor<User> {
    3. }

    service

    1. // 多条件查询用户信息
    2. public Page<User> multiQueryUser(int page, int size, String name, String position) {
    3.     Specification<User> spec = new Specification<User>() {
    4.         @Override
    5.         public Predicate toPredicate(Root<User> root, CriteriaQuery<?> criteriaQuery, CriteriaBuilder criteriaBuilder) {
    6.             List<Predicate> predicates = new ArrayList<>();
    7.             predicates.add(criteriaBuilder.notEqual(root.get("authority"), User.ADMIN_AUTHORITY));
    8.             if ("" != name) {
    9.                 // 根据姓名模糊查询
    10.                 predicates.add(criteriaBuilder.like(root.get("name"), "%" + name + "%"));
    11.             }
    12.             if ("" != position) {
    13.                 // 根据学位模糊查询
    14.                 predicates.add(criteriaBuilder.equal(root.get("position"), position));
    15.             }
    16.             Predicate[] arr = new Predicate[predicates.size()];
    17.             return criteriaBuilder.and(predicates.toArray(arr));
    18.         }
    19.     };
    21.     Pageable pageable = PageRequest.of(page, size, Sort.by("id").descending());
    22.     return userRepository.findAll(spec, pageable);
    23. }

    controller

    1. // 根据条件分页筛选用户
    2. @PostMapping("/user/query/{page}")
    3. public Map queryUser(@RequestBody QueryUserVO vo, @PathVariable int page) {
    4.     Page<User> pages = userService.multiQueryUser(page, 10, vo.getName(), vo.getPosition());
    5.     return Map.of("content", pages.getContent(), "total", pages.getTotalElements());
    6. }