How can I use Java Enums with Amazon DynamoDB and AWS SDK v2?

Issue

I am trying to implement a simple java event-handler lambda for AWS. It receives sqs events and should make appropriate updates to the dynamoDB table.

One of the attributes in this table is a status field that has 4 defined states; therefore I wanted to use an enum class in java and map it to this attribute.

Under AWS SDK v1 I could use the @DynamoDBTypeConvertedEnum annotation. But it does not exist anymore in v2. Instead, there is the @DynamoDbConvertedBy() which receives a converter class reference. There is also an EnumAttributeConverter class which should work nicely with it.

But for some reason, it does not work. The following is a snip from my current code:

@Data
@DynamoDbBean
@NoArgsConstructor
public class Task{

@Getter(onMethod_ = {@DynamoDbPartitionKey})  
    String id; 

...

@Getter(onMethod_ = {@DynamoDbConvertedBy(EnumAttributeConverter.class)})
    ExportTaskStatus status;
}

The enum looks as follows:

@RequiredArgsConstructor
public enum TaskStatus {
    @JsonProperty("running") PROCESSING(1),
    @JsonProperty("succeeded") COMPLETED(2),
    @JsonProperty("cancelled") CANCELED(3),
    @JsonProperty("failed") FAILED(4);

    private final int order;
}

With this, I get the following exception when launching the application:

Class 'class software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.EnumAttributeConverter' appears to have no default constructor thus cannot be used with the BeanTableSchema

Solution

Solution based on watkinsmatthewp Answer:

public class TaskStatusConverter implements AttributeConverter<TaskStatus> {
    @Delegate
    private final EnumAttributeConverter<TaskStatus> converter;

    public TaskStatusConverter() {
        converter = EnumAttributeConverter.create(TaskStatus.class);
    }
}

Task status attribute looks like this:

@Getter(onMethod_ = {@DynamoDbConvertedBy(TaskStatusConverter.class)})
TaskStatus status;

Answered By - 3Fish