아주 간단한 CRUD 개발 연습

개발환경 : IntelliJ IDEA , H2 DataBase, JAVA 11

스프링 부트 스타터 사이트에서 스프링 프로젝트 생성
https://start.spring.io

• 프로젝트 선택
  • Project : Gradle Project
  • Spring Boot : 2.3.x
  • Language : Java
  • Java : 11

• Project Metadata

  • groupId : hello
  • artifactId: hello-spring

• Dependencies : Spring Web, Hateoas, H2 database

H2 Database 설치 및 설정방법 를 참고하자

 

환경설정 build.gradle 파일에 jdbc, h2 database 관련 라이브러리 추가

implementation 'org.springframework.boot:spring-boot-starter-jdbc' 
runtimeOnly 'com.h2database:h2'
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=create-drop

 

스프링 부트 데이터베이스 연결 설정 추가
resources/application.properties

spring.datasource.url=jdbc:h2:tcp://localhost/~/test
spring.datasource.driver-class-name=org.h2.Driver

Domain

package com.iseunghan.accounts;

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

@Entity  
public class Account {

    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;

    private String name;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

Controller

package com.iseunghan.accounts;

import static org.springframework.hateoas.server.mvc.ControllerLinkBuilder.linkTo;

import java.net.URI;  
import java.util.List;  
import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;  
import org.springframework.http.MediaType;  
import org.springframework.http.ResponseEntity;  
import org.springframework.web.bind.annotation.DeleteMapping;  
import org.springframework.web.bind.annotation.GetMapping;  
import org.springframework.web.bind.annotation.PathVariable;  
import org.springframework.web.bind.annotation.PostMapping;  
import org.springframework.web.bind.annotation.PutMapping;  
import org.springframework.web.bind.annotation.RequestBody;  
import org.springframework.web.bind.annotation.RequestMapping;  
import org.springframework.web.bind.annotation.RestController;

@RestController  
@RequestMapping("/accounts")  
public class AccountController {  
@Autowired  
AccountService accountService;

@GetMapping()
public ResponseEntity findAll() {
    List<Account> accountList = accountService.findAll();
    return ResponseEntity.ok(accountList);
}

@GetMapping("/{name}")
public ResponseEntity findByName(@PathVariable String name) {
    Optional<Account> account =  accountService.findByName(name);
    return ResponseEntity.ok(accountService.findByName(name));
}

/*@GetMapping("/{id}")
public ResponseEntity findById(@PathVariable Integer id) {
    return ResponseEntity.ok(accountService.findById(id));
}*/

@PostMapping(produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity insertAccount(@RequestBody Account insertDTO) {
    Account account = accountService.join(insertDTO);

    URI createUri = linkTo(AccountController.class).slash(account.getId()).toUri();
    return ResponseEntity.created(createUri).body(account);
}

@PutMapping(produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity updateAccount(@RequestBody Account updateDTO) {
    Account account = accountService.join(updateDTO);

    URI createUri = linkTo(AccountController.class).slash(account.getId()).toUri();
    return ResponseEntity.created(createUri).body(account);
}

@DeleteMapping(produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity deleteAccount(@RequestBody Account deleteDTO) {
    accountService.deleteAccount(deleteDTO);
    return ResponseEntity.ok().build();
}
}

Service

package com.iseunghan.accounts;

import java.util.List;  
import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;  
import org.springframework.stereotype.Service;

@Service  
public class AccountService {

@Autowired
AccountRepository accountRepository;

public List<Account> findAll() {
    return accountRepository.findAll();
}


public Optional<Account> findByName(String name) {
    return accountRepository.findByName(name);
}


public Optional<Account> findById(Integer id) {
    return accountRepository.findById(id);
}


public Account join(Account insertDTO) {
    validateDuplicateException(insertDTO);
    return accountRepository.save(insertDTO);
}


public void deleteAccount(Account deleteDTO) {
    accountRepository.delete(deleteDTO);
}


public void validateDuplicateException(Account account) {
    findByName(account.getName())
        .ifPresent(m ->{
            throw new IllegalStateException("이미 존재하는 회원입니다.");
        });
}
}

Repository

package com.iseunghan.accounts;

import java.util.List;  
import java.util.Optional;

import org.springframework.stereotype.Repository;

@Repository  
public interface AccountRepository {  
	Account save(Account account);  
	Optional findById(Integer id);  
	Optional findByName(String name);  
	void delete(Account delete);  
	List findAll();  
}

repository 구현체 Spring Data JPA

package com.iseunghan.accounts;

import java.util.Optional;

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

public interface SpringDataJpaAccountRepository extends JpaRepository<Account, Integer>, AccountRepository{  
	Optional findByName(String name);  
	void delete(Account delete);  
}