让所有的孩子和它的大孩子 - 冬眠

Question

我的表结构如下

req_id parent_req_id
1        null
2        1
3        1
4        1
5        2
6        2
7        3

我需要编写一个HQL查询，如果输入为1，我需要检索1,2,3,4,5,6,7。由于2,3,4是1和5,6,7的直系子女，因此是其孙子。请在下面找到hiberate的bean结构

            @Entity
            @Table(name = "requirements")
            public class RequirementsDTO implements Serializable {
                private static final long serialVersionUID = 1L;
                @Id
                @GenericGenerator(name="generator", strategy="increment")
                @GeneratedValue(generator="generator")
                @Basic(optional = false)
                @Column(name = "req_id")
                private Integer reqId;
                @Column(name = "req_name")
                private String reqName;
                @Column(name = "req_desc")
                private String reqDesc;
                @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER, mappedBy = "reqId")
                private List<RequirementActorsDTO> requirementActorsDTOList;
                @OneToMany(mappedBy = "parentReqId")
                private List<RequirementsDTO> requirementsDTOList;
                @JoinColumn(name = "parent_req_id", referencedColumnName = "req_id")
                @ManyToOne
                private RequirementsDTO parentReqId;
                //getters and setters
            }