[Spring] 입문_스프링JdbcTemplate

스프링JdbcTemplate

• 순수Jdbc와 동일한 환경설정
• 순수Jdbc의 반복코드 제거
• SQL은 직접 작성

1. 스프링 JdbcTemplate 회원 리포지토리

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{

    public final JdbcTemplate jdbcTemplate;

    @Autowired  // 생성자 하나면 @Autowired 생략 가능능
    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());  // 쿼리짤필요없이 insert됨

        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", memberRowMapper());
    }

    private RowMapper<Member> memberRowMapper() {
        return (rs, rowNum) -> {  // replace with lambda
            Member member = new Member();
            member.setId(rs.getLong("id"));
            member.setName(rs.getString("name"));
            return member;
        };
    }
}

2. SpringConfig(JdbcTemplate사용하도록 스프링 설정 변경)

@Configuration
public class SpringConfig {

    private final DataSource dataSource;
 
    public SpringConfig(DataSource dataSource) {
        this.dataSource = dataSource;
    }
    
    @Bean
    public MemberRepository memberRepository() {
        return new JdbcTemplateMemberRepository(dataSource);
    }
 }