21장 동적 쿼리와 성능 최적화 조회 - Builder 사용

1)

MemberTeamDto.java

package study.querydsl.dto;

import com.querydsl.core.annotations.QueryProjection;
import lombok.Data;

@Data
public class MemberTeamDto {

    private Long memberId;
    private String username;
    private int age;
    private Long teamId;
    private String teamName;

//    @QueryProjection
    public MemberTeamDto(Long memberId, String username, int age, Long teamId, String teamName) {
        this.memberId = memberId;
        this.username = username;
        this.age = age;
        this.teamId = teamId;
        this.teamName = teamName;
    }
}

MemberSearchCondition.java

package study.querydsl.dto;

import lombok.Data;

@Data
public class MemberSearchCondition {
    // 회원명, 팀명, 나이(ageGoe, ageLoe)

    private String username;
    private String teamName;
    private Integer ageGoe;
    private Integer ageLoe;
}

MemberJpaRepository.java

public List<MemberTeamDto> searchByBuilder(MemberSearchCondition condition) {

        BooleanBuilder builder = new BooleanBuilder();

        if (hasText(condition.getUsername())) {
            builder.and(member.username.eq(condition.getUsername()));
        }
        if (hasText(condition.getTeamName())) {
            builder.and(team.name.eq(condition.getTeamName()));
        }
        if (condition.getAgeGoe() != null) {
            builder.and(member.age.goe(condition.getAgeGoe()));
        }
        if (condition.getAgeLoe() != null) {
            builder.and(member.age.loe(condition.getAgeLoe()));
        }

//        return queryFactory
//                .select(new QMemberTeamDto(
//                        member.id.as("memberId"),
//                        member.username,
//                        member.age,
//                        team.id.as("teamId"),
//                        team.name
//                ))
//                .from(member)
//                .leftJoin(member.team, team)
//                .where(builder)
//                .fetch();

        return queryFactory
                .select(
                        Projections.constructor(
                                MemberTeamDto.class,
                        member.id.as("memberId"),
                        member.username,
                        member.age,
                        team.id.as("teamId"),
                        team.name
                ))
                .from(member)
                .leftJoin(member.team, team)
                .where(builder)
                .fetch();
    }

MemberJpaRepositoryTest.java

@Test
    public void searchTest() {

        Team teamA = new Team("teamA");
        Team teamB = new Team("teamB");

        em.persist(teamA);
        em.persist(teamB);

        Member member1 = new Member("member1", 10, teamA);
        Member member2 = new Member("member2", 20, teamA);
        Member member3 = new Member("member3", 30, teamB);
        Member member4 = new Member("member4", 40, teamB);

        em.persist(member1);
        em.persist(member2);
        em.persist(member3);
        em.persist(member4);

        em.flush();
        em.clear();

        MemberSearchCondition condition = new MemberSearchCondition();
        condition.setAgeGoe(35);
        condition.setAgeLoe(40);
        condition.setTeamName("teamB");

        List<MemberTeamDto> result = memberJpaRepository.searchByBuilder(condition);
        assertThat(result).extracting("username").containsExactly("member4");

    }