Pagination and Sorting With
Spring Data JPA
Pagination is very useful when we have to deal with large
set of data and we want to present it to the view layer in smaller
data sets.
We also need to sort that data by some criteria while
applying paging.
In this tutorial,
we will explain how to implement pagination and
sort using Spring Data JPA and access throgh the GET request.
Further you can use any view logic to display the data
but here we will just use get api
Repository:
@Repository
public interface TodoJPARepository extends JpaRepository<Todo, Long>{
List<Todo> findByUsername(String username);
Page<Todo> findByUsername(String username,
Pageable pageable);
}
Suppose I need the sorted
and pageable data when get request is sent to below URL:
GET : http://127.0.0.1:8080/jpa/users/dinesh/todos/v2/1/3?sortField=id&sortDirection=desc
{
"currentPage": 1,
"totalPages": 4,
"totalItems": 10,
"sortField": "id",
"sortDirection": "asc",
"todosList": [
{
"id": 11010,
"username": "dinesh",
"description": "Learn Spring Boot5 D",
"targetDate": "2020-09-10T03:52:05.232+0000",
"done": false
},
{
"id": 11009,
"username": "dinesh",
"description": "Learn Spring Boot4 D",
"targetDate": "2020-09-10T03:52:05.232+0000",
"done": false
},
{
"id": 11008,
"username": "dinesh",
"description": "Learn Spring Boot3 D",
"targetDate": "2020-09-10T03:52:05.232+0000",
"done": false
}
]
}
Controller Get Method Logic:
@GetMapping("/jpa/users/{username}/todos/v2/{page}/{pagesize}")
public TodoResponse getUserTodos(
@PathVariable(value = "username") String username,
@PathVariable(value = "page") int page,
@PathVariable(value = "pagesize") int pagesize,
@RequestParam(value = "sortField",
defaultValue = "targetDate") String sortField,
@RequestParam(value = "sortDirection", defaultValue = "ASC") String sortDirection)
{
//Response Object
TodoResponse todoResponse = new TodoResponse();
// Sorting
// Create
Sort method based on the request parameter
Sort sort = sortDirection.equalsIgnoreCase(Sort.Direction.ASC.name()) ? Sort.by(sortField).ascending() : Sort.by(sortField).descending();
// Create PageRequest Object and pass page and sorting
parameter
Pageable pageable = PageRequest.of(page - 1, pagesize, sort);
Page<Todo> pageofTodo = todoService.findByUsername(username, pageable);
List<Todo> getTodosList = pageofTodo.getContent();
todoResponse.setCurrentPage(page);
todoResponse.setTotalItems(pageofTodo.getTotalElements());
todoResponse.setTotalPages(pageofTodo.getTotalPages());
todoResponse.setSortField(sortField);
todoResponse.setSortDirection(sortDirection.equals("asc") ?
"desc" : "asc");
todoResponse.setTodosList(getTodosList);
// Return Response
return todoResponse;
}
Supporting Classes:
public class TodoResponse implements Serializable{
private static final long serialVersionUID = 1L;
private int currentPage;
private int totalPages;
private long totalItems;
private String sortField;
private String sortDirection;
private List<Todo> todosList;
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@Entity
public class Todo {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String username;
private String description;
private Date targetDate;
private boolean isDone;
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