聚合的实现三

DDD 学习笔记 | 极客时间 | 手把手教你落地 DDD

从数据库中查询出聚合根、其下所有关联对象

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package chapter17.unjuanable.adapter.driven.persistence.orgmng;
// imports...

@Repository
public class EmpRepositoryJdbc implements EmpRepository {
   //声明 JdbcTemplate 和各个 SimpleJdbcInsert ...
   // 构造器、其他方法 ...

    @Override
    public Optional<Emp> findById(Long tenantId, Long id) {
        Optional<RebuiltEmp> empMaybe = retrieveEmp(tenantId, id);
        if (empMaybe.isPresent()) {
            RebuiltEmp emp = empMaybe.get();
            retrieveSkills(emp);
            retrieveExperiences(emp);
            retrievePosts(emp);
            return Optional.of(emp);
        } else {
            return Optional.empty();
        }
    }

    private Optional<RebuiltEmp> retrieveEmp(Long tenantId, Long id) {
        String sql = " select org_id, num, id_num, name "
                + " , gender_code, dob, status_code "
                + " from emp "
                + " where id = ? and tenant_id = ? ";

        RebuiltEmp emp = jdbc.queryForObject(sql,
                (rs, rowNum) -> {
                    RebuiltEmp newEmp = new RebuiltEmp(tenantId
                            , id
                            , rs.getTimestamp("create_at").toLocalDateTime()
                            , rs.getLong("created_by"));

                    newEmp.resetOrgId(rs.getLong("org_id"))
                          .resetNum(rs.getString("num"))
                          .resetIdNum(rs.getString("id_num"))
                          .resetName(rs.getString("name"))
                          .resetGender(Gender.ofCode(
                                    rs.getString("gender_code")))
                          .resetDob(rs.getDate("dob").toLocalDate())
                          .resetStatus(EmpStatus.ofCode(
                                      rs.getString("status_code")));
                    return newEmp;
                },
                id, tenantId);
                
        return Optional.ofNullable(emp);
    }

    private void retrieveSkills(RebuiltEmp emp) {
        String sql = " select id, tenant_id, skill_type_id, level, duration "
                + " from skill "
                + " where tenant_id = ? and emp_id = ? ";

        List<Map<String, Object>> skills = jdbc.queryForList(
                                sql, emp.getTenantId(), emp.getId());

        skills.forEach(skill -> emp.reAddSkill(
                    (Long) skill.get("id")
                    , (Long) skill.get("skill_type_id")
                    , SkillLevel.ofCode((String) skill.get("level_code"))
                    , (Integer) skill.get("duration")
                    , (Long) skill.get("created_by")
        });

    }

    private void retrieveExperiences(RebuiltEmp emp) {
        //与retrieveSkill 类似 ...
    }

    private void retrievePosts(RebuiltEmp emp) {
        //与retrieveSkill 类似 ...
    }
}

save() 通过 changingStatus 判断是新增还是更新

16 课文末代码

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package chapter16.unjuanable.common.framework.domain;
import static chapter16.unjuanable.common.framework.domain.ChangingStatus.*;

public abstract class AuditableEntity {
    protected ChangingStatus changingStatus = NEW;
    // 其他属性、构造器 ...

    public ChangingStatus getChangingStatus() {
        return changingStatus;
    }

    public void toUpdate() {
        this.changingStatus = UPDATED;
    }

    public void toDelete() {
        this.changingStatus = DELETED;
    }

    public void toUnChang() {
        this.changingStatus = UNCHANGED;
    }
    
    // 其他方法 ...
}

save()

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package chapter17.unjuanable.adapter.driven.persistence.orgmng;
// imports ...

@Repository
public class EmpRepositoryJdbc implements EmpRepository {

    final JdbcTemplate jdbc;
    final SimpleJdbcInsert empInsert;
    final SimpleJdbcInsert skillInsert;
    final SimpleJdbcInsert WorkExperienceInsert;
    final SimpleJdbcInsert empPostInsert;

    @Autowired
    public EmpRepositoryJdbc(JdbcTemplate jdbc) {
        this.jdbc = jdbc;
        this.empInsert = new SimpleJdbcInsert(jdbc)
                .withTableName("emp")
                .usingGeneratedKeyColumns("id");
        //初始化其他 SimpleJdbcInsert ...
    }

    @Override
    public void save(Emp emp) {
        saveEmp(emp);
        emp.getSkills().forEach(s -> saveSkill(emp, s));
        emp.getExperiences().forEach(e -> saveWorkExperience(emp, e));
        emp.getEmpPosts().forEach(p -> saveEmpPost(emp, p));
    }

    private void saveEmp(Emp emp) {
        switch (emp.getChangingStatus()) {
            case NEW:
                insertEmpRecord(emp);
                break;
            case UPDATED:
                updateEmpRecord(emp);
                break;
        }
    }

    private void insertEmpRecord(Emp emp) {
        Map<String, Object> parms = Map.of(
                "tenant_id", emp.getTenantId()
                , "org_id", emp.getOrgId()
                , "num", emp.getNum()
                , "id_num", emp.getIdNum()
                , "name", emp.getName()
                , "gender", emp.getGender().code()
                , "dob", emp.getDob()
                , "status", emp.getStatus().code()
                , "created_at", emp.getCreatedAt()
                , "created_by", emp.getCreatedBy()
        );

        Number createdId = empInsert.executeAndReturnKey(parms);

        forceSet(emp, "id", createdId.longValue());
    }

    private void updateEmpRecord(Emp emp) {
        String sql = "update emp " +
                " set org_id = ?" +
                ", num = ?" +
                ", id_num =? " +
                ", name = ?" +
                ", gender =?" +
                ", dob = ?" +
                ", status =?" +
                ", last_updated_at =?" +
                ", last_updated_by =? " +
                " where tenant_id = ? and id = ? ";
        this.jdbc.update(sql
                , emp.getOrgId()
                , emp.getNum()
                , emp.getIdNum()
                , emp.getName()
                , emp.getGender().code()
                , emp.getDob()
                , emp.getStatus()
                , emp.getLastUpdatedAt()
                , emp.getLastUpdatedBy()
                , emp.getTenantId()
                , emp.getId());
    }

    private void saveSkill(Emp emp, Skill skill) {
        switch (skill.getChangingStatus()) {
            case NEW:
                insertSkillRecord(skill, emp.getId());
                break;
            case UPDATED:
                updateSkillRecord(skill);
                break;
            case DELETED:
                deleteSkillRecord(skill);
                break;

        }
    }

    private void insertSkillRecord(Skill skill, Long empId) {
        Map<String, Object> parms = Map.of(
            "emp_id", empId,
            "tenant_id", skill.getTenantId(),
            "skill_type_id", skill.getSkillTypeId(),
            "level_code", skill.getLevel().code(),
            "duration", skill.getDuration(),
            "created_at", skill.getCreatedAt(),
            "created_by", skill.getCreatedBy()
            );

        Number createdId = skillInsert.executeAndReturnKey(parms);

        forceSet(skill, "id", createdId.longValue());
    }

    private void updateSkillRecord(Skill skill) {
        String sql = "update skill " 
                    + " set level_code = ?" 
                    + ", duration = ?" 
                    + ", last_updated_at = ?" 
                    + ", last_updated_by = ?" 
                    + " where tenant_id = ? and id = ? ";
        this.jdbc.update(sql
                , skill.getSkillTypeId()
                , skill.getDuration()
                , skill.getLastUpdatedAt()
                , skill.getLastUpdatedBy()
                , skill.getTenantId()
                , skill.getId());
    }


    private void deleteSkillRecord(Skill skill) {
        this.jdbc.update("delete from skll where tenant_id = ? "
                       + " and id = ?"
                , skill.getTenantId()
                , skill.getId());
    }

    private void saveWorkExperience(Emp emp, WorkExperience e) {
        // 与 saveSkill( ) 类似...
    }

    private void saveEmpPostRecord(Emp emp, EmpPost p) {
        // 与 saveSkill( ) 类似...
    }

}