Hướng dẫn sử dụng Spring Data JPA
NỘI DUNG BÀI VIẾT
Trong bài viết này, chúng tôi sẽ chỉ cho bạn cách sử dụng Spring Boot + Spring Data JPA để lưu dữ liệu vào database H2 trong bộ nhớ và cách cũng truy vấn dữ liệu. Cùng bắt đầu luôn nhé 😉
Chúng ta có thể tạo project tại đây. Thêm các dependency như hình dưới rồi chọn GENERATE.
1. Project Directory
2. Maven
pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.5.3</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com</groupId>
<artifactId>hdd</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>hdd</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
Code language: HTML, XML (xml)Tổng hợp 200+ tài liệu, sách, bài thực hành, video hướng dẫn lập trình… từ cơ bản đến nâng cao
application.properties:
logging.level.org.springframework=INFO
logging.level.com.hdd=INFO
logging.level.com.zaxxer=DEBUG
logging.level.root=ERROR
spring.datasource.hikari.connectionTimeout=20000
spring.datasource.hikari.maximumPoolSize=5
spring.datasource.hikari.poolName=HikariPoolZZZ3. Spring Data JPA
Product.java
package com.hdd;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity
public class Product {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
public Product() {
}
public Product(String name) {
this.name = name;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Code language: JavaScript (javascript)Tài liệu học lập trình: https://codegym.vn/tai-nguyen-hoc-lap-trinh/
ProductRepository.java
package com.hdd;
import org.springframework.data.repository.CrudRepository;
import java.util.List;
public interface ProductRepository extends CrudRepository<Product, Long> {
List<Product> findByName(String name);
}
Code language: PHP (php)4. @SpringBootApplication trong Spring Boot
Tạo 3 đối tượng vào H2 database và kiểm tra method find().
HddApplication.java
package com.hdd;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class HddApplication implements CommandLineRunner {
private static final Logger log = LoggerFactory.getLogger(HddApplication.class);
public static void main(String[] args) {
SpringApplication.run(HddApplication.class, args);
}
@Autowired
private ProductRepository productRepository;
@Override
public void run(String... args) {
log.info("HddApplication...");
productRepository.save(new Product("Computer"));
productRepository.save(new Product("Phone"));
productRepository.save(new Product("Book"));
System.out.println("\nfindAll()");
productRepository.findAll().forEach(System.out::println);
System.out.println("\nfindById(1L)");
productRepository.findById(1l).ifPresent(System.out::println);
System.out.println("\nfindByName('Computer')");
productRepository.findByName("Computer").forEach(System.out::println);
}
}
Code language: JavaScript (javascript)5. Unit Test
@DataJpaTest và TestEntityManager để kiểm tra Spring data JPA repository.
ProductRepositoryTest.java
package com.hdd;
import org.assertj.core.api.Assertions;
import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
import org.springframework.boot.test.autoconfigure.orm.jpa.TestEntityManager;
import org.springframework.test.context.junit4.SpringRunner;
import java.util.List;
@RunWith(SpringRunner.class)
@DataJpaTest
public class ProductRepositoryTest {
@Autowired
private TestEntityManager entityManager;
@Autowired
private ProductRepository productRepository;
@Test
public void testFindByName() {
entityManager.persist(new Product("Book1"));
List<Product> products = productRepository.findByName("Book1");
Assert.assertEquals(1, products.size());
Assertions.assertThat(products).extracting(Product::getName).containsOnly("Book1");
}
}
Code language: JavaScript (javascript)6. Demo
Mở teminal lên và run câu lệnh sau:
mvn spring-boot:runCode language: CSS (css)Kết quả:
findAll()
com.hdd.Product@64f3991e
com.hdd.Product@3bf5911d
com.hdd.Product@1de30c31
findById(1L)
com.hdd.Product@238ad211
findByName('Computer')
com.hdd.Product@92e2c93
Code language: CSS (css)Như vậy chúng ta đã hiểu sơ qua về Spring Data JPA qua 1 project Spring Boot. Chúc các bạn thành công! 😂
Download source: Github.
Tham khảo 1 số bài viết liên quan:
https://hocspringboot.net/2021/05/25/huong-dan-annotation-query-nativequery-trong-spring-data/
Tài liệu học lập trình: https://codegym.vn/tai-nguyen-hoc-lap-trinh/
Tham khảo khóa học lập trình tại: https://codegym.vn/
hay quá