Sunday 18 April 2021

Spring data jpa: in query method example

 

Keyword expressions In, IsIn are used to execute in query.

 

Example 1: Find all the employee whose id is in given list

 

List<Employee> findByIdIn(List<Integer> ids);

Above method generate following in query.

SELECT * FROM employee e WHERE e.id in (id1, id2, ...);

 

Example 2: Find all the employees whose id is in given list or whose firstName is in given list.

 

List<Employee> findByIdInOrFirstNameIn(List<Integer> ids, List<String> firstNames);

Above method generate following query.

 

SELECT * FROM employee e WHERE e.id in (id1, id2, ...) OR e.firstName in (name1, name2...)

 

Example 3: Find all the employees whose id is in given list and whose firstName is in given list.

 

List<Employee> findByIdInAndFirstNameIn(List<Integer> ids, List<String> firstNames);

Above method generate following query.

 

SELECT * FROM employee e WHERE e.id in (id1, id2, ...) AND e.firstName in (name1, name2...)

 

Follow below step-by-step procedure to build complete working application.

 

Step 1: Create new maven project ‘in-query-method’.

 

Step 2: Update pom.xml with maven dependencies.

 

pom.xml

<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>
    <groupId>com.sample.app</groupId>
    <artifactId>in-query-method</artifactId>
    <version>1</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.0</version>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>


    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>


        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
        </dependency>


    </dependencies>
</project>

 

Step 3: Create application.properties file under src/main/resources folder.

 

application.properties

 

logging.level.root=WARN
logging.level.org.hibernate=ERROR

## H2 specific properties
spring.h2.console.enabled=true
spring.h2.console.path=/h2

spring.datasource.url=jdbc:h2:file:~/db/myOrg.db;DB_CLOSE_ON_EXIT=FALSE;DB_CLOSE_DELAY=-1;

spring.datasource.username=krishna
spring.datasource.password=password123

spring.datasource.driverClassName=org.h2.Driver

## JPA specific properties
# Creates the schema, destroying previous data.
spring.jpa.hibernate.ddl-auto=create

spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

spring.jpa.show-sql=false
spring.jpa.properties.hibernate.format_sql=false

## Database connection pooling properties
# Number of ms to wait before throwing an exception if no connection is available.
spring.datasource.max-wait=10000

# Maximum number of active connections that can be allocated from this pool at the same time.
spring.datasource.tomcat.max-active=10
spring.datasource.tomcat.max-idle=5
spring.datasource.tomcat.min-idle=3

 

Step 4: Define employee entity class.

 

Employee.java

 

package com.sample.app.entity;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "my_employee")
public class Employee {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int id;

    @Column(name = "first_name")
    private String firstName;

    @Column(name = "last_name")
    private String lastName;

    @Column(name = "age")
    private int age;

    @Column(name = "salary")
    private double salary;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    public static EmployeeBuilder builder() {
        return new EmployeeBuilder();
    }

    public static class EmployeeBuilder {
        private Employee emp;

        public EmployeeBuilder() {
            emp = new Employee();
        }

        public EmployeeBuilder firstName(String firstName) {
            emp.setFirstName(firstName);
            return this;
        }

        public EmployeeBuilder lastName(String lastName) {
            emp.setLastName(lastName);
            return this;
        }

        public EmployeeBuilder age(int age) {
            emp.setAge(age);
            return this;
        }

        public EmployeeBuilder salary(double salary) {
            emp.setSalary(salary);
            return this;
        }

        public Employee build() {
            return emp;
        }
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();
        builder.append("Employee [id=").append(id).append(", firstName=").append(firstName).append(", lastName=")
                .append(lastName).append(", age=").append(age).append(", salary=").append(salary).append("]");
        return builder.toString();
    }

}

 

Step 5: Define EmployeeRepository interface.

 

EmployeeRepository.java

 

package com.sample.app.repository;

import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;

import com.sample.app.entity.Employee;

public interface EmployeeRepository extends JpaRepository<Employee, Integer> {
    
    // IN queries
    List<Employee> findByIdIn(List<Integer> ids);

    List<Employee> findByIdInOrFirstNameIn(List<Integer> ids, List<String> firstNames);

    List<Employee> findByIdInAndFirstNameIn(List<Integer> ids, List<String> firstNames);

    // NOTIN queries
    List<Employee> findByIdNotIn(List<Integer> ids);

    List<Employee> findByIdNotInOrFirstNameNotIn(List<Integer> ids, List<String> firstNames);

    // NOTIN and IN query
    List<Employee> findByIdNotInAndFirstNameIn(List<Integer> ids, List<String> firstNames);

}

 

Step 6: Define main application class.

 

App.java

 

package com.sample.app;

import java.util.Arrays;
import java.util.List;

import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

import com.sample.app.entity.Employee;
import com.sample.app.repository.EmployeeRepository;

@SpringBootApplication
public class App {

    public static void main(String args[]) {
        SpringApplication.run(App.class, args);
    }

    public void printEmployees(Iterable<Employee> emps, String msg) {
        System.out.println(msg);
        for (Employee emp : emps) {
            System.out.println(emp);
        }

        System.out.println();
    }

    @Bean
    public CommandLineRunner demo(EmployeeRepository employeeRepository) {
        return (args) -> {
            Employee emp1 = Employee.builder().firstName("Ram").lastName("Gurram").age(32).salary(100000.23).build();
            Employee emp2 = Employee.builder().firstName("Ram").lastName("Chelli").age(43).salary(60000).build();
            Employee emp3 = Employee.builder().firstName("Gopi").lastName("Battu").age(45).salary(1000000).build();
            Employee emp4 = Employee.builder().firstName("Ram").lastName("Srikanth").age(39).salary(60000).build();
            Employee emp5 = Employee.builder().firstName("Surendra").lastName("Sami").age(32).salary(100000.23).build();

            employeeRepository.save(emp1);
            employeeRepository.save(emp2);
            employeeRepository.save(emp3);
            employeeRepository.save(emp4);
            employeeRepository.save(emp5);

            List<Employee> emps = employeeRepository.findAll();
            printEmployees(emps, "All the employees information");

            emps = employeeRepository.findByIdIn(Arrays.asList(2, 3, 5));
            printEmployees(emps, "Employees with id 2, 3, 5");

            emps = employeeRepository.findByIdInOrFirstNameIn(Arrays.asList(2, 3), Arrays.asList("Ram"));
            printEmployees(emps, "Employees where id is in [2, 3] or firstName in ['Ram']");

            emps = employeeRepository.findByIdInAndFirstNameIn(Arrays.asList(2, 3), Arrays.asList("Ram"));
            printEmployees(emps, "Employees where id is in [2, 3] and firstName in ['Ram']");
        };
    }

}

 

Total project structure looks like below.

 


Run App.java, you will see below messages in console.

All the employees information
Employee [id=1, firstName=Ram, lastName=Gurram, age=32, salary=100000.23]
Employee [id=2, firstName=Ram, lastName=Chelli, age=43, salary=60000.0]
Employee [id=3, firstName=Gopi, lastName=Battu, age=45, salary=1000000.0]
Employee [id=4, firstName=Ram, lastName=Srikanth, age=39, salary=60000.0]
Employee [id=5, firstName=Surendra, lastName=Sami, age=32, salary=100000.23]

Employees with id 2, 3, 5
Employee [id=2, firstName=Ram, lastName=Chelli, age=43, salary=60000.0]
Employee [id=3, firstName=Gopi, lastName=Battu, age=45, salary=1000000.0]
Employee [id=5, firstName=Surendra, lastName=Sami, age=32, salary=100000.23]

Employees where id is in [2, 3] or firstName in ['Ram']
Employee [id=1, firstName=Ram, lastName=Gurram, age=32, salary=100000.23]
Employee [id=2, firstName=Ram, lastName=Chelli, age=43, salary=60000.0]
Employee [id=3, firstName=Gopi, lastName=Battu, age=45, salary=1000000.0]
Employee [id=4, firstName=Ram, lastName=Srikanth, age=39, salary=60000.0]

Employees where id is in [2, 3] and firstName in ['Ram']
Employee [id=2, firstName=Ram, lastName=Chelli, age=43, salary=60000.0]


You can download complete working application from below link.

https://github.com/harikrishna553/springboot/tree/master/jpa/in-query-method



 

 

 

 

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