Spring Data JPA应用排序，分页以及where子句

Question

I am currently Using Spring JPA and utilizing the Sorting and Pagination as described here -

How to query data via Spring data JPA by sort and pageable both out of box？

Now my question is how do I apply a 'where' clause to this?

Eg

where PRODUCT_NAME='abc';

Answer 1

Just create a query method in your repository interface for this.

Take a look in the docs, here .

Add a query method with paging and where clause.

Page<User> findByLastname(String lastname, Pageable pageable);

So you can find User by a property "lastname" and configure Paging settings.

Answer 2

The easiest way I could find is to use QueryDSL or Specifications . I prefer QueryDSL.

Answer 3

To fetch Spring Data JPA apply sorting, pagination along with a where clause check bellow codes

1. Entity class

    @Entity @Table(name = "users") Public Class User{ private String name; private Integer id; private String email; // add required setter getter// } 

2. Repository class

    @Repository("userRepository") @Transactional` public interface UserRepository extends JpaRepository<User, Integer>{ } 

3. Service layer to pass where clause using Example object and Pagination+Sorting together using Pagable and Sort Class. We will implement Pageable in controller to inject Sorting logic then will pass that Pagable object to service Layer.

     @Service Public class UserService{ public Page<User> getUserListPaginated(`EXAMPLE<User>` searchTerm, Pageable pageable) { return userRepo.findAll(searchTerm,pageable); } } 

Example<T> does not take the attribute if its value is null. for that I used Integer id in Entity class as I can set it's value null for first call

4. Now Controller Class

    @Controller Public class UserController{ @Autowired UserService userService; @GetMapping("/users") public String users(Model model,@RequestParam(value="page",defaultValue = "0") Integer pageNumber, @SortDefault(sort = "name", direction = Sort.Direction.ASC) Sort sort){ Pageable pageable = PageRequest.of(pageNumber,10, sort); Example<User> searchTerm = Example.of(new User()); Page<User> userList = userService.getUserListPaginated(searchTerm, pageable); } }