JPA分组查询遇到问题怎么办？自定义查询方法详解

@RestController
@RequestMapping("/jpa")
@Api(value="/test", tags="JPA分组")
public class JPAController {
    @Autowired
    private EntityManager entityManager;
    @ApiOperation(value="JPA分组", notes = "JPA分组测试")//swagger文档注解
    @GetMapping("student")
    public List<StudentVO> jpa(){
        CriteriaBuilder cb = entityManager.getCriteriaBuilder();
        CriteriaQuery<Tuple> cq = cb.createTupleQuery();
        Root<Student> root = cq.from(Student.class);//具体实体的Root
        root.alias("o");//别名
        cq.multiselect(root.get("name").alias("name"),root.get("age").alias("age"));
        Predicate where = cb.conjunction();
        //增加查询条件
        cq.where(where).groupBy(root.get("name"),root.get("age"));
        List<Tuple> tuples = entityManager.createQuery(cq).getResultList();
        //结果集
        List<StudentVO> result = new ArrayList<>();
        for(Tuple tuple : tuples){
            result.add(new StudentVO(tuple.get(0).toString(),tuple.get(1).toString()));
        }
        return result;
    }
}

/**
 * 查询月份集合（JPA分组）
 * @param type
 * @return
 */
public Integer countNum(MonthlyParamVO param,String type,String isF ,Collection<Integer> functionSonList,Collection<Integer> orgIds){
    //初始化结果集
    List<String> monthList = new ArrayList<String>();
    //初始化JPA查询
    CriteriaBuilder cb = entityManager.getCriteriaBuilder();
    CriteriaQuery<Tuple> cq = cb.createTupleQuery();
    Root<AttendanceMonthlyReportEntity> root = cq.from(AttendanceMonthlyReportEntity.class);
    //加条件
    if("missDays".equals(type)){
        cq.multiselect(cb.sum(root.get("missDays")));
    }else if("absentDays".equals(type)){
        cq.multiselect(cb.sum(root.get("absentDays")));
    }else if("lateEarly".equals(type)){
        cq.multiselect(cb.sum(root.get("lateEarly")));
    }else if("notPunched".equals(type)){
        cq.multiselect(cb.sum(root.get("notPunched")));
    }
    //查询条件where
    List<Predicate> predicates = new ArrayList<>();
    if(StringUtils.isNotBlank(param.getZhName())){
        predicates.add(cb.equal(root.get("zhName"),param.getZhName()));
    }
    if(null!=param.getOrgIds()&&param.getOrgIds().size()!=0){
        predicates.add(root.get("orgId").in(orgIds));
    }
    if(StringUtils.isNotBlank(param.getYear())&&StringUtils.isBlank(param.getMonth())){
        predicates.add(cb.equal(root.get("attendanceMonth"),param.getYear()+"%"));
    }
    if(StringUtils.isNotBlank(param.getZhName())&&StringUtils.isNotBlank(param.getMonth())){
        predicates.add(cb.equal(root.get("attendanceMonth"),param.getYear()+"-"+param.getMonth()));
    }
    if("Y".equals(isF)){
        //加入需求限制
        predicates.add(cb.or(root.get("orgId").in(functionSonList),cb.like(root.get("positionLevel"),"F")));
    }
    cq.where(predicates.toArray(new Predicate[predicates.size()]));
    List<Tuple> tuples = entityManager.createQuery(cq).getResultList();
    //求和
    Integer count = 0;
    for(Tuple tuple : tuples){
        if(tuple.get(0) instanceof Float){
            count = ((Float) tuple.get(0)).intValue();
        }else if(tuple.get(0) instanceof Integer){
            count = (Integer) tuple.get(0);
        }else if(tuple.get(0) instanceof Double){
            count = ((Double) tuple.get(0)).intValue();
        }
    }
    return count;
}