@Override
public List<ProjectStatusDTO> getProjectStatus(Long departId) {
QProject qProject = QProject.project;
Predicate predicate = qProject.isNotNull().or(qProject.isNull());
predicate = StringUtils.isEmpty(departId) ? predicate : ExpressionUtils.and(predicate, qProject.departId.eq(departId));
List<ProjectStatusDTO> projectStatusDTOList = jpaQueryFactory.select(
Projections.bean(
ProjectStatusDTO.class,
qProject.status,
qProject.id.count().as("count")
)
)
.from(qProject)
.where(predicate)
.groupBy(qProject.status)
.fetch();
return projectStatusDTOList;
}核心代码：
Projections.bean(
ProjectStatusDTO.class,
qProject.status,
qProject.id.count().as("count")
)注意点：
如果实体中的字段属性和自定义的对象的属性不一样，请使用 .as("自定义对象中的属性名称")
