Spring JPA＆amp; amp;懒惰加载自我指涉属性

Question

假设我有一个名为BusinessCategory的类：

    @Entity
    public class BusinessCategory implements Serializable{

    @Id
    private int id;

    @Column(nullable = false)
    private String name;

    @ManyToOne
    private BusinessCategory parentCategory;
    ...
    }

其中要延迟加载parentCategory。另一个名为Transaction的类，其中包含BusinessCategory：

    @Entity
    public class Transaction implements Serializable{

    @Id
    private long id;

    @Column(nullable = false)
    private String description;

    @ManyToOne
    private BusinessCategory businessCategory;
    ...
    }

在@Service中，我检索一个列表，该列表依次处理其中一个步骤涉及：

BusinessCategory category = transaction.getBusinessCategory();
if(transaction.getBusinessCategory().getParentCategory()!=null){
   ...
   /** do stuff **/
}

真正奇怪的是，即使我的测试事务有一个带有父级的BusinessCategory，transaction.getBusinessCategory().getParentCategory()只返回null（在调试器中看作handler对象）。甚至更奇怪的事实是我能够直接访问parentCategory的属性。观看窗口截图：

我还确认，当访问parentCategory的某个属性时，会立即触发MySQL查询（这很好）。我打开了MySQL的general_log＆amp;尾随它。

1933 Query  select businessca0_.id as id1_3_0_, businessca0_.dateCreated as dateCrea2_3_0_, businessca0_.dateUpdated as dateUpda3_3_0_, businessca0_.categoryType as category4_3_0_, businessca0_.depth as depth5_3_0_, businessca0_.mappedIds as mappedId6_3_0_, businessca0_.name as name7_3_0_, businessca0_.parentCategory_id as parentCa8_3_0_ from BusinessCategory businessca0_ where businessca0_.id=10013

这似乎是一个Spring框架漏洞？