Dynamodb - Convert enumerator collection

Question

Is there a way to convert a collection of enums? I've tried the following without success:

@DynamoDBTypeConvertedEnum
@DynamoDBAttribute(attributeName="myEnums")
private Collection<MyEnum> myEnums;

score 4 · Accepted Answer · answered Dec 20 '17 at 12:40

4

In order to save it as collection (i.e. set of strings), please use @DynamoDBTyped annotation with SS attribute type.

@DynamoDBTyped(DynamoDBAttributeType.SS)
@DynamoDBAttribute(attributeName = "myEnums")
public Set<MyEnum> getMyEnums() {
    return myEnums;
}

answered Dec 20 '17 at 12:40

notionquest

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I would be interested to know if this method works out. Definitely the best option if it works. I've found problems with Dynamo 'unconverting' Sets correctly before though (without a custom converter). – F_SO_K Dec 20 '17 at 14:35

score 2 · Answer 2 · edited Dec 20 '17 at 17:23

myEnums is a Set of enums, not an enum itself.

DynamoDBTyped

The enum type is only supported by override or custom converter

Because you have a set of enums, you will need to use a customer converter. So remove the @DynamoDBTypeConvertedEnum annotation and use a custom converter. You can see an example I have posted before here. Its a generic Set example but it will work for your enum Set.

EDIT: i.e. use DynamoDBTypeConverted

Dynamodb - Convert enumerator collection

2 Answers2