Get Embed Document based on DBRef in MongoDB using Spring data - mongodb

Question

I'm developing a spring boot application. I've 2 models that is
PersonEntity
#Data
#Document(collection = "products")
public class ProductEntity implements Serializable {
private static final long serialVersionUID = -8118791879505582652L;
#MongoId(FieldType.STRING)
private String id;
#Indexed
#Field("name")
private String name;
#Field("category")
#DBRef(lazy = true)
private CategoryEntity category;
// getters and setters
}
CategoryEntity
#Data
#Document(collection = "categories")
public class CategoryEntity implements Serializable {
private static final long serialVersionUID = -636356399519451958L;
#MongoId(value = FieldType.STRING)
private String id;
#Field("name")
private String name;
#Field("desc")
private String desc;
public CategoryEntity(String id) {
super();
this.id = id;
}
// getters and setters
}
when I'm saving data into DB then stored data is
Products Document
{
"_id": {
"$oid": "6141eeab92432109463ae8c4"
},
"name": "Adidas Running Shoes",
"category": {
"$ref": "categories",
"$id": "614049d91042cf40b5b9b304"
}
}
Categories Document
{
"_id": {
"$oid": "614049d91042cf40b5b9b304"
},
"name": "Shoes",
"desc": "Men's running Shoes",
}
But when I'm try to findAll() the ProductEntity the data by using Spring-Data-MongoDB the category will return null.
public List<ProductModel> getProducts() {
List<ProductEntity> entities = productRepo.findAll();
return entities.stream().map(entity -> {
ProductModel product = new ProductModel();
BeanUtils.copyProperties(entity, product);
if (Objects.nonNull(entity.getCategory())) {
BeanUtils.copyProperties(entity.getCategory(), product.getCategory());
}
return product;
}).collect(Collectors.toList());
}
and I need the output will be in below format.
{
"_id": {
"$oid": "6141eeab92432109463ae8c4"
},
"name": "Adidas Running Shoes",
"category": {
"_id": {
"$oid": "614049d91042cf40b5b9b304"
},
"name": "Shoes",
"desc": "Men's running Shoes",
}
}
Please let me know how to get desired output.

Answer 1

I've done a minor change and issue has been resolved. I've changed
from
#MongoId(value = FieldType.STRING)
private String id;
to
#MongoId(value = FieldType.OBJECT_ID)
private ObjectId id;
in the both entities and code works!