How do you implement pagination and sorting in Spring Boot?

Table of Contents

Introduction

Pagination and sorting are essential features when dealing with large datasets in a Spring Boot application. They help to optimize performance by limiting the number of records returned at once and allowing users to view the data in an ordered manner. Spring Boot, together with Spring Data JPA, makes it easy to implement these features with minimal effort. In this guide, we will walk you through how to implement pagination and sorting in a Spring Boot application using Spring Data JPA.

Steps to Implement Pagination and Sorting

1. Set Up Spring Boot Project with Spring Data JPA

Before implementing pagination and sorting, ensure that your Spring Boot project is set up with Spring Data JPA and a database connection. You can use either an in-memory database (like H2) or any other database like MySQL, PostgreSQL, etc.

Add Dependencies in **pom.xml**

Configure **application.properties**

2. Create a JPA Entity

For pagination and sorting to work, we need a JPA entity that will map to a table in the database. For example, we will create a Product entity.

Example: **Product** Entity

3. Create a Repository Interface with Pagination and Sorting

Spring Data JPA provides an easy way to implement pagination and sorting by extending JpaRepository or PagingAndSortingRepository. You can use methods like findAll(Pageable pageable) and findAll(Sort sort) to fetch paginated and sorted results.

Example: **ProductRepository** Interface

In this repository:

  • The findByNameContaining method allows you to filter products by name, and it returns a paginated result (Page<Product>). The Pageable parameter will handle the pagination and sorting.

4. Implement Pagination and Sorting in the Service Layer

Now, in your service layer, you can use the repository's pagination and sorting methods to fetch the data accordingly. You can customize the Pageable object to specify the page number, size, and sorting.

Example: **ProductService** Class

In this service:

  • getProducts() fetches all products with pagination and sorting.
  • getProductsByName() fetches products based on the name and applies pagination and sorting.

5. Create a Controller to Handle HTTP Requests

You will now create a controller that takes pagination and sorting parameters from the user (for example, through query parameters) and passes them to the service layer.

Example: **ProductController** Class

In this controller:

  • The @RequestParam annotations are used to accept the page number (page), page size (size), the field to sort by (sortBy), and the sorting direction (ascending).
  • These parameters are passed to the service layer to fetch paginated and sorted results.
  • The results are added to the Model, and you can display them in a Thymeleaf template.

6. Create the Thymeleaf Template to Display Paginated and Sorted Data

Finally, you can create a Thymeleaf template to display the paginated and sorted products.

Example: **product/list.html**

In this template:

  • You use Thymeleaf's th:href to create links that preserve the current page and sorting criteria, allowing users to navigate through pages and sort by different fields.

Conclusion

Pagination and sorting are crucial for efficiently displaying large datasets in Spring Boot applications. By using Spring Data JPA’s Pageable and Sort classes, you can easily implement pagination and sorting with minimal configuration. The example provided demonstrates how to set up pagination, sorting, and display the results using Thymeleaf templates. This approach helps to improve performance and user experience when dealing with large volumes of data in a Spring Boot application.

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