spring.h2.console.enabled=true
spring.datasource.url=jdbc:h2:mem:testdb
jdbc:h2:mem:testdb
implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
@NoArgsConstructor // 기본생성자를 대신 생성해줍니다.
@Entity // 테이블임을 나타냅니다.
public class Course {
@Id // ID 값, Primary Key로 사용하겠다는 뜻입니다.
@GeneratedValue(strategy = GenerationType.AUTO) // 자동 증가 명령입니다.
private Long id;
@Column(nullable = false) // 컬럼 값이고 반드시 값이 존재해야 함을 나타냅니다.
private String title;
@Column(nullable = false)
private String tutor;
public String getTitle() {
return this.title;
}
public String getTutor() {
return this.tutor;
}
public Course(String title, String tutor) {
this.title = title;
this.tutor = tutor;
}
}
/* 같은 개념
CREATE TABLE IF NOT EXISTS courses (
id bigint(5) NOT NULL AUTO_INCREMENT,
title varchar(255) NOT NULL,
tutor varchar(255) NOT NULL,
PRIMARY KEY (id)
);
*/
public interface CourseRepository extends JpaRepository<Course, Long> {
}
spring.jpa.show-sql=true
// Week02Application.java 의 main 함수 아래에 붙여주세요.
@Bean
public CommandLineRunner demo(CourseRepository repository) {
return (args) -> {
};
}
@Bean
public CommandLineRunner demo(CourseRepository repository) {
return (args) -> {
Course course1 = new Course("웹 개발의 봄 Spring", "남병관");
repository.save(course1);
List<Course> courseList = repository.findAll();
for (int i=0; i<courseList.size(); i++) {
Course c = courseList.get(i);
System.out.println(c.getTitle());
System.out.println(c.getTutor());
}
};
}
package com.sparta.week02.domain;
import org.springframework.data.annotation.CreatedDate;
import org.springframework.data.annotation.LastModifiedDate;
import org.springframework.data.jpa.domain.support.AuditingEntityListener;
import javax.persistence.EntityListeners;
import javax.persistence.MappedSuperclass;
import java.time.LocalDateTime;
@MappedSuperclass // 상속했을 때, 컬럼으로 인식하게 합니다.
@EntityListeners(AuditingEntityListener.class) // 생성/수정 시간을 자동으로 반영하도록 설정
public abstract class Timestamped {
@CreatedDate // 생성일자임을 나타냅니다.
private LocalDateTime createdAt;
@LastModifiedDate // 마지막 수정일자임을 나타냅니다.
private LocalDateTime modifiedAt;
}
class Course extends Timestamped {
@EnableJpaAuditing
@SpringBootApplication
public class Week02Application {
→ 생성 (Create)
→ 조회 (Read)
→ 변경 (Update)
→ 삭제 (Delete)
// 데이터 저장하기
repository.save(new Course("프론트엔드의 꽃, 리액트", "임민영"));
// 데이터 전부 조회하기
List<Course> courseList = repository.findAll();
for (int i=0; i<courseList.size(); i++) {
Course course = courseList.get(i);
System.out.println(course.getId());
System.out.println(course.getTitle());
System.out.println(course.getTutor());
}
// 데이터 하나 조회하기
Course course = repository.findById(1L).orElseThrow(
() -> new IllegalArgumentException("해당 아이디가 존재하지 않습니다.")
);
public void update(Course course) {
this.title = course.title;
this.tutor = course.tutor;
}
@Service // 스프링에게 이 클래스는 서비스임을 명시
public class CourseService {
// final: 서비스에게 꼭 필요한 녀석임을 명시
private final CourseRepository courseRepository;
// 생성자를 통해, Service 클래스를 만들 때 꼭 Repository를 넣어주도록
// 스프링에게 알려줌
public CourseService(CourseRepository courseRepository) {
this.courseRepository = courseRepository;
}
@Transactional // SQL 쿼리가 일어나야 함을 스프링에게 알려줌
public Long update(Long id, Course course) {
Course course1 = courseRepository.findById(id).orElseThrow(
() -> new IllegalArgumentException("해당 아이디가 존재하지 않습니다.")
);
course1.update(course);
return course1.getId();
}
}
@Bean
public CommandLineRunner demo(CourseRepository courseRepository, CourseService courseService) {
return (args) -> {
courseRepository.save(new Course("프론트엔드의 꽃, 리액트", "임민영"));
System.out.println("데이터 인쇄");
List<Course> courseList = courseRepository.findAll();
for (int i=0; i<courseList.size(); i++) {
Course course = courseList.get(i);
System.out.println(course.getId());
System.out.println(course.getTitle());
System.out.println(course.getTutor());
}
Course new_course = new Course("웹개발의 봄, Spring", "임민영");
courseService.update(1L, new_course);
courseList = courseRepository.findAll();
for (int i=0; i<courseList.size(); i++) {
Course course = courseList.get(i);
System.out.println(course.getId());
System.out.println(course.getTitle());
System.out.println(course.getTutor());
}
};
}
@Bean
public CommandLineRunner demo(CourseRepository courseRepository, CourseService courseService) {
return (args) -> {
courseRepository.save(new Course("프론트엔드의 꽃, 리액트", "임민영"));
System.out.println("데이터 인쇄");
List<Course> courseList = courseRepository.findAll();
for (int i=0; i<courseList.size(); i++) {
Course course = courseList.get(i);
System.out.println(course.getId());
System.out.println(course.getTitle());
System.out.println(course.getTutor());
}
Course new_course = new Course("웹개발의 봄, Spring", "임민영");
courseService.update(1L, new_course);
courseList = courseRepository.findAll();
for (int i=0; i<courseList.size(); i++) {
Course course = courseList.get(i);
System.out.println(course.getId());
System.out.println(course.getTitle());
System.out.println(course.getTutor());
}
courseRepository.deleteAll();
};
}