@DynamoDBDocument not working for a Map<Object, Object>

[namral]

I tried to use @DynamoDBDocument to serialize a POJO that looks like this :

`
@DynamoDBDocument
public class Metadata {
Map<Object, Object> metadata;

    public Metadata() {
    }

    public Metadata(Map<Object, Object> metadata) {
        this.metadata = metadata;
    }

    @DynamoDBAttribute
    public Map<Object, Object> getMetadata() {
        return stateMetadata;
    }

    public void setMetadata(Map<Object, Object> metadata) {
        this.metadata = metadata;
    }
}

@DynamoDBTable(tableName = "REPLACED_BY_CONFIG")
public class ProductItem {
private Metadata metadata;

     @DynamoDBAttribute
     public Metadata getMetadata() {
           return metadata;
     }

}
`

http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DynamoDBMapper.Annotations.html#DynamoDBMapper.Annotations.DynamoDBDocument

It throws the following exception :
Caused by: com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: not supported; requires @DynamoDBTyped or @DynamoDBTypeConverted

I was able to get this to work by adding the following annotation to the getter method in ProductItem
@DynamoDBTypeConverted(converter = MetadataTypeConverter.class)

I was wondering why I see this behavior ?

[millems]

At this time, maps can only be converted automatically without an annotation when the key type is a string. I've passed along the request to support more types (or at least a better error message) here: aws/aws-sdk-java-v2#35

[dimPhotobox]

I still confirm, on the 18th of december 2017, aws-sdk.version=1.11.246, key as Integer are still unsupported...

[deevant07]

At this time, maps can only be converted automatically without an annotation when the key type is a string. I've passed along the request to support more types (or at least a better error message) here: aws/aws-sdk-java-v2#35

--> Map<String,CustomObject> is also not working in the latest version 1.11.140... any changes again

[biniama]

Adding @DynamoDBDocument to the Custom Class made it work for me.
https://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/services/dynamodbv2/datamodeling/DynamoDBDocument.html

A dynamoDB table will not be created for this object.
This way, you don't need to implement a Converter class which implements DynamoDBTypeConverter