Use of DynamoDB annotations in nested objects

Question

I am trying to use DynamoDB annotations in nested objects as below:

@DynamoDBTable(tableName=xyz)
class entity1{
    @DynamoDBAttribute
    @DynamoDBTypeConvertedJson
    private List<UserAction> userActions;
}

class UserAction{
    @DynamoDBAutoGeneratedKey
    private String actionId;

    @DynamoDBAttribute
    @DynamoDBAutoGeneratedTimestamp(strategy = DynamoDBAutoGenerateStrategy.CREATE)
    private Long createdTime;
}

I dont see the above attributes are auto generated in UserAction class. I would like to know if these annotation usages are supported in nested objects or not. Please suggest.

score 2 · Answer 1 · answered Aug 15 '20 at 10:38

2

Add @DynamoDbDocument annotation on UserAction class. This annotation will ensure the instance of UserAction class is correctly serialized to a Dynamo DB sub-document before persisting in table.

@DynamoDbDocument
class UserAction{
    //...............
    //...............
}

answered Aug 15 '20 at 10:38

mango

548
3
8

Thank you but this dint help. I added that annotatiion you mentioned but no luck. – Deepak Aug 15 '20 at 20:09
2

any idea about the sdk v2 equivalent of @DynamoDBDocument? – Anwesh Mohapatra Sep 22 '21 at 07:09
@AnweshMohapatra Check [this](https://github.com/aws/aws-sdk-java-v2/issues/2265) – Hasitha Jayawardana Oct 22 '22 at 21:37

score 1 · Answer 2 · answered Oct 22 '22 at 21:42

If anyone is looking for a v2 equivalent of @DynamoDBDocument, the following is the annotated way of doing it. For more information check this out.

@DynamoDbBean
class entity1 {
    
    private List<UserAction> userActions;
}

@DynamoDbBean
class UserAction {

    private String actionId;

    private Long createdTime;
}

Use of DynamoDB annotations in nested objects

2 Answers2