Spring boot 시작하기 - 11강(H2 Database연결-jdbc template방식)

1. build.gradle 설정파일로 가서 아래와 같이 코드를 추가해줍니다.

 

2. application.properties 파일에 가서 아래와 같이 수정해줍니다.

 

3. JdbcTemplateMemberRepository 클래스를 추가해줍니다.

package hello.hellospring.repository;

import hello.hellospring.domain.Member;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.simple.SimpleJdbcInsert;

import javax.sql.DataSource;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;

public class JdbcTemplateMemberRepository implements MemberRepository{

    private final JdbcTemplate jdbcTemplate;

    //Datasource 자동으로 인젝션
    @Autowired  // 생성자가 1개일 경우 @Autowired는 생략 가능
    public JdbcTemplateMemberRepository(DataSource dataSource){
        jdbcTemplate = new JdbcTemplate(dataSource);
    }

    @Override
    public Member save(Member member) {
        SimpleJdbcInsert jdbcInsert = new SimpleJdbcInsert(jdbcTemplate);
        jdbcInsert.withTableName("member").usingGeneratedKeyColumns("id");

        Map<String, Object> parameters = new HashMap<>();
        parameters.put("name", member.getName());

        Number key = jdbcInsert.executeAndReturnKey(new MapSqlParameterSource(parameters));
        member.setId(key.longValue());
        return member;
    }

    @Override
    public Optional<Member> findById(Long id) {
        List<Member> result = jdbcTemplate.query("select * from member where id = ?",memberRowMapper(), id);
        return result.stream().findAny();
    }

    @Override
    public Optional<Member> findByName(String name) {
        List<Member> result = jdbcTemplate.query("select * from member where name = ?",memberRowMapper(), name);
        return result.stream().findAny();
    }

    @Override
    public List<Member> findAll() {
        return jdbcTemplate.query("select * from member where name = ?",memberRowMapper());
    }

    private RowMapper<Member> memberRowMapper(){
        return (rs, rowNum) -> {

            Member member = new Member();
            member.setId(rs.getLong("id"));
            member.setName(rs.getString("name"));
            return member;
        };
    }
}

4. SpringConfig클래스 수정(조립)

SpringConfig클래스에서 MemberRepository의 인자로 JdbcTemplateMemberRepository를 넘겨줍니다.

package hello.hellospring;

import hello.hellospring.repository.JdbcTemplateMemberRepository;
import hello.hellospring.repository.MemberRepository;
import hello.hellospring.repository.MemoryMemberRepository;
import hello.hellospring.service.MemberService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;

@Configuration
public class SpringConfig {

    private DataSource dataSource;

    @Autowired
    public SpringConfig(DataSource dataSource){
        this.dataSource = dataSource;
    }

    @Bean
    public MemberService memberService(){
        return new MemberService(memberRepository());
    }

    @Bean
    public MemberRepository memberRepository(){
        //return new MemoryMemberRepository();
        return new JdbcTemplateMemberRepository(dataSource);
    }
}

 

순수 JDBC로 하는 것보다 중복코드를 줄여주어 훨씬 간단히 작성할 수 있다고 합니다. 

 

~~ 끝 ~~