JSON ID数组一对多关系

如何解决JSON ID数组一对多关系

我有一个与json关联的关系，该类别可能具有分类数组（分类ID）我想获取类别中的分类列表。

{
  "assortments": [
    {
      "assortmentId": "80a7f7f0-4b07-4cbd-900a-888d29923b79","code": "assortmentCode1","name": "assortmentName1"
    },{
      "assortmentId": "15b16e87-ebb6-447e-80f3-fd9be26b308c","code": "assortmentCode2","name": "assortmentName2"
    },{
      "assortmentId": "23d94649-99b9-44d3-8b29-d1a84a6828e0","code": "assortmentCode3","name": "assortmentName3"
    }
  ],"categories": [
    {
      "categoryId": "bd711f3c-2d6a-4129-9b3f-e6fb37e98f8c","code": "categoryCode1","name": "categoryName1","assortments": []
    },{
      "categoryId": "dc219c34-f979-4665-a7e8-38c7c8db8017","code": "categoryCode2","name": "categoryName2","assortments": [
        "23d94649-99b9-44d3-8b29-d1a84a6828e0","15b16e87-ebb6-447e-80f3-fd9be26b308c"
      ]
    },{
      "categoryId": "f3babb00-6898-48c3-afab-8de12f60d65c","code": "categoryCode3","name": "categoryName3","assortments": [
        "80a7f7f0-4b07-4cbd-900a-888d29923b79"
      ]
    }
  ]
}

到目前为止，我已经创建了Assortment和Category模型，DAO，并且都遵循Room文档并在CategoryDao中创建了一对多的查询；

public class CategoryWithAssortments {
@Embedded public OSCategory category;
@Relation(
        parentColumn = "categoryId",entityColumn = "categoryOwnerId"
)
public List<OSAssortment> assortments;}

查询：

@Transaction
@Query("SELECT * FROM os_categories")
public List<CategoryWithAssortments> gettest();

分类始终为空。我如何实现自己想要的？