Spring Boot pagination
last modified July 27, 2023
In this article we show how to paginate data in a Spring application.
Spring is a popular Java application framework and Spring Boot is an evolution of Spring that helps create stand-alone, production-grade Spring based applications easily.
Pagination
Pagination is the process of dividing data into suitable chunks to save resources.
PagingAndSortingRepository
PagingAndSortingRepository
is an extension of CrudRepository
to provide additional methods to retrieve entities using pagination and sorting.
Spring Boot paginate example
In the following application, we create a simple Spring Boot Restful application which allows to paginate data.
build.gradle ... src ├───main │ ├───java │ │ └───com │ │ └───zetcode │ │ │ Application.java │ │ ├───controller │ │ │ MyController.java │ │ ├───model │ │ │ Country.java │ │ ├───repository │ │ │ CountryRepository.java │ │ └───service │ │ CountryService.java │ │ ICountryService.java │ └───resources │ application.properties │ import.sql └───test └───java
This is the project structure.
plugins { id 'org.springframework.boot' version '3.1.1' id 'io.spring.dependency-management' version '1.1.0' id 'java' } group = 'com.zetcode' version = '0.0.1-SNAPSHOT' sourceCompatibility = '17' repositories { mavenCentral() } dependencies { implementation 'org.springframework.boot:spring-boot-starter-web' implementation 'org.springframework.boot:spring-boot-starter-data-jpa' runtimeOnly 'com.h2database:h2' }
This is the Gradle build file. The h2
dependency includes the H2
database driver.
The spring-boot-starter-web
enables web applications, both classic
and RESTFul. It uses Tomcat as the default embedded container. The
spring-boot-starter-data-jpa
is a starter for using Spring Data JPA
with Hibernate.
spring.main.banner-mode=off spring.jpa.hibernate.ddl-auto=create-drop
In the application.properties
file we write various configuration
settings of a Spring Boot application. With the banner-mode
property we turn off the Spring banner.
The create-drop
option automatically creates and drops the database
schema. The H2 database is run in memory.
INSERT INTO countries(name, population) VALUES('China', 1382050000); INSERT INTO countries(name, population) VALUES('India', 1313210000); INSERT INTO countries(name, population) VALUES('USA', 324666000); INSERT INTO countries(name, population) VALUES('Indonesia', 260581000); INSERT INTO countries(name, population) VALUES('Brazil', 207221000); INSERT INTO countries(name, population) VALUES('Pakistan', 196626000); INSERT INTO countries(name, population) VALUES('Nigeria', 186988000); INSERT INTO countries(name, population) VALUES('Bangladesh', 162099000); INSERT INTO countries(name, population) VALUES('Russia', 146838000); INSERT INTO countries(name, population) VALUES('Japan', 126830000); INSERT INTO countries(name, population) VALUES('Mexico', 122273000); INSERT INTO countries(name, population) VALUES('Philippines', 103738000); INSERT INTO countries(name, population) VALUES('Ethiopia', 101853000); INSERT INTO countries(name, population) VALUES('Vietnam', 92700000); INSERT INTO countries(name, population) VALUES('Egypt', 92641000); INSERT INTO countries(name, population) VALUES('Germany', 82800000); INSERT INTO countries(name, population) VALUES('the Congo', 82243000); INSERT INTO countries(name, population) VALUES('Iran', 82800000); INSERT INTO countries(name, population) VALUES('Turkey', 79814000); INSERT INTO countries(name, population) VALUES('Thailand', 68147000); INSERT INTO countries(name, population) VALUES('France', 66984000); INSERT INTO countries(name, population) VALUES('United Kingdom', 60589000); INSERT INTO countries(name, population) VALUES('South Africa', 55908000); INSERT INTO countries(name, population) VALUES('Myanmar', 51446000); INSERT INTO countries(name, population) VALUES('South Korea', 68147000); INSERT INTO countries(name, population) VALUES('Colombia', 49129000); INSERT INTO countries(name, population) VALUES('Kenya', 47251000); INSERT INTO countries(name, population) VALUES('Spain', 46812000); INSERT INTO countries(name, population) VALUES('Argentina', 43850000); INSERT INTO countries(name, population) VALUES('Ukraine', 42603000); INSERT INTO countries(name, population) VALUES('Sudan', 41176000); INSERT INTO countries(name, population) VALUES('Algeria', 40400000); INSERT INTO countries(name, population) VALUES('Poland', 38439000); INSERT INTO countries(name, population) VALUES('Canada', 37742154); INSERT INTO countries(name, population) VALUES('Morocco', 36910560); INSERT INTO countries(name, population) VALUES('Saudi Arabia', 34813871); INSERT INTO countries(name, population) VALUES('Uzbekistan', 33469203); INSERT INTO countries(name, population) VALUES('Peru', 32971854); INSERT INTO countries(name, population) VALUES('Angola', 32866272); INSERT INTO countries(name, population) VALUES('Malaysia', 32365999); INSERT INTO countries(name, population) VALUES('Mozambique', 31255435); INSERT INTO countries(name, population) VALUES('Ghana', 31072940); INSERT INTO countries(name, population) VALUES('Yemen', 29825964); INSERT INTO countries(name, population) VALUES('Nepal', 29136808); INSERT INTO countries(name, population) VALUES('Venezuela', 28435940);
The schema is automatically created by Hibernate; later, the
import.sql
file is executed to fill the table with data.
package com.zetcode.model; import jakarta.persistence.Entity; import jakarta.persistence.GeneratedValue; import jakarta.persistence.GenerationType; import jakarta.persistence.Id; import jakarta.persistence.Table; import java.util.Objects; @Entity @Table(name = "countries") public class Country { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; private String name; private int population; public Country() { } public Country(Long id, String name, int population) { this.id = id; this.name = name; this.population = population; } public Long getId() { return id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getPopulation() { return population; } public void setPopulation(int population) { this.population = population; } @Override public boolean equals(Object o) { if (this == o) return true; if (o == null || getClass() != o.getClass()) return false; Country country = (Country) o; return population == country.population && Objects.equals(id, country.id) && Objects.equals(name, country.name); } @Override public int hashCode() { return Objects.hash(id, name, population); } @Override public String toString() { final StringBuilder sb = new StringBuilder("Country{"); sb.append("id=").append(id); sb.append(", name='").append(name).append('\''); sb.append(", population=").append(population); sb.append('}'); return sb.toString(); } }
This is the Country
entity. Each entity must have at least two
annotations defined: @Entity
and @Id
. Previously, we
have set the ddl-auto
option to create-drop
which means
that Hibernate will create the table schema from this entity.
@Entity @Table(name = "countries") public class Country {
The @Entity
annotation specifies that the class is an
entity and is mapped to a database table. The @Table
annotation
specifies the name of the database table to be used for mapping.
@Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id;
The @Id
annotation specifies the primary key of an entity and
the @GeneratedValue
gives the generation strategy for the values
of primary keys.
package com.zetcode.repository; import com.zetcode.model.Country; import org.springframework.data.repository.PagingAndSortingRepository; import org.springframework.stereotype.Repository; @Repository public interface CountryRepository extends PagingAndSortingRepository<Country, Long> { }
CountryRepository
is decorated with the @Repository
annotation. By extending from the Spring PagingAndSortingRepository
,
we have some methods to paginate data.
package com.zetcode.service; import com.zetcode.model.Country; import java.util.List; public interface ICountryService { List<Country> findPaginated(int pageNo, int pageSize); }
ICountryService
contains the findPaginated
contract method. It contains two parameters: the page number and the
page size.
package com.zetcode.service; import com.zetcode.model.Country; import com.zetcode.repository.CountryRepository; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.domain.Page; import org.springframework.data.domain.PageRequest; import org.springframework.data.domain.Pageable; import org.springframework.stereotype.Service; import java.util.List; @Service public class CountryService implements ICountryService { private final CountryRepository repository; @Autowired public CountryService(CountryRepository repository) { this.repository = repository; } @Override public List<Country> findPaginated(int pageNo, int pageSize) { Pageable paging = PageRequest.of(pageNo, pageSize); Page<Country> pagedResult = repository.findAll(paging); return pagedResult.toList(); } }
CountryService
contains the implementation of the
findPaginated
method.
private final CountryRepository repository; @Autowired public CountryService(CountryRepository repository) { this.repository = repository; }
CountryRepository
is injected into the field.
Pageable paging = PageRequest.of(pageNo, pageSize); Page<Country> pagedResult = repository.findAll(paging);
A PageRequest
is created from the supplied values
and passed to the findAll
repository method.
package com.zetcode.controller; import com.zetcode.model.Country; import com.zetcode.service.ICountryService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RestController; import java.util.List; @RestController public class MyController { private final ICountryService countryService; @Autowired public MyController(ICountryService countryService) { this.countryService = countryService; } @GetMapping("/countries/{pageNo}/{pageSize}") public List<Country> getPaginatedCountries(@PathVariable int pageNo, @PathVariable int pageSize) { return countryService.findPaginated(pageNo, pageSize); } }
MyController
handles a request from the client.
private final ICountryService countryService; @Autowired public MyController(ICountryService countryService) { this.countryService = countryService; }
ICountryService
is injected into the countryService
field.
@GetMapping("/countries/{pageNo}/{pageSize}") public List<Country> getPaginatedCountries(@PathVariable int pageNo, @PathVariable int pageSize) { return countryService.findPaginated(pageNo, pageSize); }
We provide the page number and page size as path variables. The values are
passed to the findPaginated
service method.
package com.zetcode; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
Application
is the entry point which sets up Spring Boot
application.
$ ./gradlew bootRun
We run the application.
$ curl localhost:8080/countries/0/5 [{"id":1,"name":"China","population":1382050000},{"id":2,"name":"India","population":1313210000}, {"id":3,"name":"USA","population":324666000},{"id":4,"name":"Indonesia","population":260581000}, {"id":5,"name":"Brazil","population":207221000}]
We get the first page of 5 rows. The indexing starts from 0.
$ curl localhost:8080/countries/1/5 [{"id":6,"name":"Pakistan","population":196626000},{"id":7,"name":"Nigeria","population":186988000}, {"id":8,"name":"Bangladesh","population":162099000},{"id":9,"name":"Russia","population":146838000}, {"id":10,"name":"Japan","population":126830000}]
We get the next page.
In this article we have shown how to create pagination in a Spring Boot application.