Hibernate: SQL query, JPQL, Hibernate named query, JPA Streamer

 1. Native query on Hibernate

package com.example.relationships.entity;

import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import lombok.*;
import org.hibernate.Hibernate;

import java.util.Objects;

@Getter
@Setter
@ToString
@RequiredArgsConstructor
@Entity
public class Student {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private Integer age;

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || Hibernate.getClass(this) != Hibernate.getClass(o)) return false;
        Student student = (Student) o;
        return id != null && Objects.equals(id, student.id);
    }

    @Override
    public int hashCode() {
        return getClass().hashCode();
    }
}
package com.example.relationships.repository;

import com.example.relationships.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;

import java.util.List;

public interface StudentRepository extends JpaRepository<Student, Long> {

    List<Student> findAllByAgeGreaterThan(int age);

    @Query(value = "select * from student where student.age > ?", nativeQuery = true)
    List<Student> getStudentsByAgeGreaterThan(int age);
}
package com.example.relationships;

import com.example.relationships.entity.Student;
import com.example.relationships.repository.StudentRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@RequiredArgsConstructor
public class RelationshipsApplication implements CommandLineRunner {

    private final StudentRepository studentRepsitory;

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

    @Override
//    @Transactional
    public void run(String... args) throws Exception {
        System.out.println("Start--------------------------------------------------");

        for (int i = 0; i < 10; i++) {
            Student s = new Student();
            s.setName("Test " + i);
            s.setAge(13 + i);
            studentRepsitory.save(s);
        }

        studentRepsitory.getStudentsByAgeGreaterThan(16).stream().forEach(System.out::println);

        System.out.println("Finish--------------------------------------------------");
    }
}

Start----------------------------------------------------

Hibernate: select * from student where student.age > ?

Student(id=5, name=Test 4, age=17)

Student(id=6, name=Test 5, age=18)

Student(id=7, name=Test 6, age=19)

Student(id=8, name=Test 7, age=20)

Student(id=9, name=Test 8, age=21)

Student(id=10, name=Test 9, age=22)

Finish--------------------------------------------------


-------------------

package com.example.relationships.repository;

import com.example.relationships.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;

import java.util.List;

public interface StudentRepository extends JpaRepository<Student, Long> {

    List<Student> findAllByAgeGreaterThan(int age);

    @Query(value = "select * from student where student.age > ?", nativeQuery = true)
    List<Student> getStudentsByAgeGreaterThan(int age);

    @Modifying
    @Query(value = "update student set name = ?2 where id = ?1", nativeQuery = true)
    Integer updateStudentNameById(int id, String name);
}
package com.example.relationships;

import com.example.relationships.entity.Student;
import com.example.relationships.repository.StudentRepository;
import jakarta.transaction.Transactional;
import lombok.RequiredArgsConstructor;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@RequiredArgsConstructor
public class RelationshipsApplication implements CommandLineRunner {

    private final StudentRepository studentRepository;

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

    @Override
    @Transactional
    public void run(String... args) throws Exception {
        System.out.println("Start----------------------------------------------------");

        for (int i = 0; i < 10; i++) {
            Student s = new Student();
            s.setName("Test " + i);
            s.setAge(13 + i);
            studentRepository.save(s);
        }

        System.out.println("Start----------------------------------------------------");

        Integer id = studentRepository.updateStudentNameById(5, "Parvin");
        System.out.println(id);

        System.out.println("Finish--------------------------------------------------");
    }
}


Start----------------------------------------------------

Hibernate: update student set name = ? where id = ?

1

Finish--------------------------------------------------

Buradaki Integer cavabi bize nece row deyishildiyini gosterir.


2. JPQL - Java Persistence Query Language

package com.example.relationships.repository;

import com.example.relationships.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;

import java.util.List;

public interface StudentRepository extends JpaRepository<Student, Long> {

    List<Student> findAllByAgeGreaterThan(int age);

    @Query(value = "select * from student s where s.age > ?", nativeQuery = true)
    List<Student> getStudentsByAgeGreaterThan(int age);

    @Modifying
    @Query(value = "update student s set name = ?2 where s.id = ?1", nativeQuery = true)
    Integer updateStudentNameById(int id, String name);

    @Query(value = "select s from Student s where s.age > ?1")
    List<Student> getStudentsByAgeGreaterThanJPQL(int age);
}
package com.example.relationships.repository;

import com.example.relationships.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;

import java.util.List;

public interface StudentRepository extends JpaRepository<Student, Long> {

    List<Student> findAllByAgeGreaterThan(int age);

    @Query(value = "select * from student where student.age > ?", nativeQuery = true)
    List<Student> getStudentsByAgeGreaterThan(int age);

    @Modifying
    @Query(value = "update student set name = ?2 where id = ?1", nativeQuery = true)
    Integer updateStudentNameById(int id, String name);

    @Query(value = "select s from Student s where s.age > ?1")
    List<Student> getStudentsByAgeGreaterThanJPQL(int age);
}


3. Hibernate named query

package com.example.relationships.entity;

import jakarta.persistence.*;
import lombok.Getter;
import lombok.RequiredArgsConstructor;
import lombok.Setter;
import lombok.ToString;
import org.hibernate.Hibernate;

import java.util.Objects;

@Getter
@Setter
@ToString
@RequiredArgsConstructor
@Entity
@NamedQueries({@NamedQuery(name = "selectStudentById", query = "select s from Student s where s.id = :id")})
public class Student {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private Integer age;

    @OneToOne(cascade = CascadeType.PERSIST, orphanRemoval = true, fetch = FetchType.LAZY)
    @JoinColumn(name = "address_id")
    private Address address;

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || Hibernate.getClass(this) != Hibernate.getClass(o)) return false;
        Student student = (Student) o;
        return id != null && Objects.equals(id, student.id);
    }

    @Override
    public int hashCode() {
        return getClass().hashCode();
    }
}


package com.example.relationships;

import com.example.relationships.entity.Address;
import com.example.relationships.entity.Student;
import com.example.relationships.repository.StudentRepository;
import jakarta.persistence.EntityManagerFactory;
import jakarta.transaction.Transactional;
import lombok.RequiredArgsConstructor;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.query.Query;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@RequiredArgsConstructor
public class RelationshipsApplication implements CommandLineRunner {

    private final EntityManagerFactory entityManagerFactory;
    private final StudentRepository studentRepository;

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

    @Override
    @Transactional
    public void run(String... args) throws Exception {
        System.out.println("Start----------------------------------------------------");

        Address address = new Address();
        address.setEmail("test@gmail.com");

        Student parvin = new Student();
        parvin.setName("Parvin");
        parvin.setAge(31);
        parvin.setAddress(address);

        studentRepository.save(parvin);

        System.out.println("Start----------------------------------------------------");

        SessionFactory sessionFactory = entityManagerFactory.unwrap(SessionFactory.class);
        Session session = sessionFactory.openSession();
        session.beginTransaction();
        Query query = session.getNamedQuery("selectStudentById").setParameter("id", 1L);
        Student student = (Student) query.uniqueResult();
        sessionFactory.close();
        System.out.println(student);
        System.out.println("Finish--------------------------------------------------");
    }
}


4. JPA Streamer

plugins {
    id 'java'
    id 'org.springframework.boot' version '3.1.2'
    id 'io.spring.dependency-management' version '1.1.2'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'

java {
    sourceCompatibility = '17'
}

configurations {
    compileOnly {
        extendsFrom annotationProcessor
    }
}

repositories {
    mavenCentral()
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'org.springframework.boot:spring-boot-starter-web'
    compileOnly 'org.projectlombok:lombok'
    runtimeOnly 'org.postgresql:postgresql'
    annotationProcessor 'org.projectlombok:lombok'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'

    // jpa streamer
    implementation 'com.speedment.jpastreamer:jpastreamer-core:3.0.3'
    annotationProcessor 'com.speedment.jpastreamer:fieldgenerator-standard:3.0.3'
}

tasks.named('test') {
    useJUnitPlatform()
}


package com.example.relationships;

import com.example.relationships.entity.Student;
import com.example.relationships.entity.Student$;
import com.example.relationships.repository.StudentRepository;
import com.speedment.jpastreamer.application.JPAStreamer;
import jakarta.persistence.EntityManagerFactory;
import jakarta.transaction.Transactional;
import lombok.RequiredArgsConstructor;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@RequiredArgsConstructor
public class RelationshipsApplication implements CommandLineRunner {

    private final EntityManagerFactory entityManagerFactory;
    private final StudentRepository studentRepository;

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

    @Override
    @Transactional
    public void run(String... args) throws Exception {
        System.out.println("Start----------------------------------------------------");

        JPAStreamer jpaStreamer = JPAStreamer.of(entityManagerFactory);

//        for (int i = 1; i < 11; i++) {
//            Student student = new Student();
//            student.setName("Test " + i);
//            student.setAge(10 + i);
//            studentRepository.save(student);
//        }

        jpaStreamer.stream(Student.class)
                .filter(Student$.age.greaterThan(15))
                .forEach(System.out::println);

        System.out.println("Finish--------------------------------------------------");
    }
}









































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