Spring Data JPA query methods are the most powerful methods, we can create query methods to select the records from the database without writing SQL queries. Behind the scenes, Spring Data JPA will create SQL queries based on the query method and execute the query for us.
Let's follow the Spring Data JPA naming convention to write a query method for the IN clause for the Product entity class.
Example: Consider the Product entity class and if we want to retrieve products with In clause then here is the Spring Data JPA query method:
We need to create a method starting with the prefix findBy followed by the field name and then In suffix - findBy[FieldName][In]
List<Product> findByNameIn(List<String> names);
Let's create a complete example to understand end-to-end.
Maven Dependencies
Add the following maven dependencies to your Spring Boot project:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</artifactId>
<scope>runtime</scope>
</dependency>
Product Entity
Let's first create a Product entity class and add the following content to it:
package net.javaguides.springdatajpacourse.entity;
import org.hibernate.annotations.CreationTimestamp;
import org.hibernate.annotations.UpdateTimestamp;
import jakarta.persistence.*;
import java.math.BigDecimal;
import java.util.Date;
@Entity
@Table(name="products")
public class Product {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
private Long id;
@Column(name = "sku")
private String sku;
@Column(name = "name")
private String name;
@Column(name = "description")
private String description;
@Column(name = "price")
private BigDecimal price;
@Column(name = "image_url")
private String imageUrl;
@Column(name = "active")
private boolean active;
@Column(name = "date_created")
@CreationTimestamp
private Date dateCreated;
@Column(name = "last_updated")
@UpdateTimestamp
private Date lastUpdated;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getSku() {
return sku;
}
public void setSku(String sku) {
this.sku = sku;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public BigDecimal getPrice() {
return price;
}
public void setPrice(BigDecimal price) {
this.price = price;
}
public String getImageUrl() {
return imageUrl;
}
public void setImageUrl(String imageUrl) {
this.imageUrl = imageUrl;
}
public boolean isActive() {
return active;
}
public void setActive(boolean active) {
this.active = active;
}
public Date getDateCreated() {
return dateCreated;
}
public void setDateCreated(Date dateCreated) {
this.dateCreated = dateCreated;
}
public Date getLastUpdated() {
return lastUpdated;
}
public void setLastUpdated(Date lastUpdated) {
this.lastUpdated = lastUpdated;
}
@Override
public String toString() {
return "Product{" +
"id=" + id +
", sku='" + sku + '\'' +
", name='" + name + '\'' +
", description='" + description + '\'' +
", price=" + price +
", imageUrl='" + imageUrl + '\'' +
", active=" + active +
", dateCreated=" + dateCreated +
", lastUpdated=" + lastUpdated +
'}';
}
}
ProductRepository
Let's create ProductRepository which extends JpaRepository and add the following code to it:
import java.util.List;
import net.javaguides.springdatajpacourse.entity.Product;
import org.springframework.data.jpa.repository.JpaRepository;
public interface ProductRepository extends JpaRepository<Product, Long> {
/**
* Return the products based on SQL in clause condition
* @param names
* @return
*/
List<Product> findByNameIn(List<String> names);
}
Configure MySQL and Hibernate Properties
Let's use the MySQL database to store and retrieve the data in this example and we gonna use Hibernate properties to create and drop tables.
Open the application.properties file and add the following configuration to it:
spring.datasource.url=jdbc:mysql://localhost:3306/ecommerce?useSSL=false
spring.datasource.username=root
spring.datasource.password=Mysql@123
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQLDialect
spring.jpa.hibernate.ddl-auto = create-drop
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true
Make sure that you will create ecommerce database before running the Spring boot application.
Also, change the MySQL username and password as per your MySQL installation on your machine.
Testing Spring Data JPA Query Method - IN Clause
In order to test the query method with IN clause that we have created, we gonna use CommandLineRunner.run() method to execute the testing code while the Spring boot application startup:
import net.javaguides.springdatajpacourse.entity.Product;
import net.javaguides.springdatajpacourse.repository.ProductRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import java.math.BigDecimal;
import java.util.Date;
import java.util.List;
@SpringBootApplication
public class SpringDataJpaCourseApplication implements CommandLineRunner{
public static void main(String[] args) throws Exception {
SpringApplication.run(SpringDataJpaCourseApplication.class, args);
}
@Autowired
private ProductRepository productRepository;
@Override
public void run(String... args) throws Exception {
Product product = new Product();
product.setName("product 1");
product.setDescription("product 1 desc");
product.setPrice(new BigDecimal(100));
product.setDateCreated(new Date());
product.setLastUpdated(new Date());
product.setSku("product 1 sku");
product.setActive(true);
product.setImageUrl("product1.png");
// save product
productRepository.save(product);
Product product2 = new Product();
product2.setName("product 2");
product2.setDescription("product 2 desc");
product2.setPrice(new BigDecimal(200));
product2.setDateCreated(new Date());
product2.setLastUpdated(new Date());
product2.setSku("product 2 sku");
product2.setActive(true);
product2.setImageUrl("product2.png");
// save product 2
productRepository.save(product2);
// products based on in condition
List<Product> productsIn = productRepository.findByNameIn(List.of("product 1","product 2"));
productsIn.forEach((p) ->
System.out.println(p));
}
}
Once Spring boot application execution completes, you can able to see Spring Data JPA (uses Hibernate as JPA provider) generated SQL statements in a console:
Hibernate:
insert
into
products
(active, date_created, description, image_url, last_updated, name, price, sku)
values
(?, ?, ?, ?, ?, ?, ?, ?)
Hibernate:
insert
into
products
(active, date_created, description, image_url, last_updated, name, price, sku)
values
(?, ?, ?, ?, ?, ?, ?, ?)
Hibernate:
select
product0_.id as id1_0_,
product0_.active as active2_0_,
product0_.date_created as date_cre3_0_,
product0_.description as descript4_0_,
product0_.image_url as image_ur5_0_,
product0_.last_updated as last_upd6_0_,
product0_.name as name7_0_,
product0_.price as price8_0_,
product0_.sku as sku9_0_
from
products product0_
where
product0_.name in (
? , ?
)
Note that the below SQL query with In clause:
select
product0_.id as id1_0_,
product0_.active as active2_0_,
product0_.date_created as date_cre3_0_,
product0_.description as descript4_0_,
product0_.image_url as image_ur5_0_,
product0_.last_updated as last_upd6_0_,
product0_.name as name7_0_,
product0_.price as price8_0_,
product0_.sku as sku9_0_
from
products product0_
where
product0_.name in (
? , ?
)
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