Dynamodbmapperexception: No Method Annotated?

In my android app, I use DynamoDb. I create a class, which is mapped with a table of database. App runs normally in debug. But if I export apk and run app, I get the DynamoDbMapper

Solution 1:

Are you using a DynamoDB table?

You need to have a hash key for the class, you should annotate the field with @DynamoDBHashKey, do you accidentally annotated it as @DynamoDBIndexHashKey? If so, you should change it back.

A similar reference can be found here

Android Amazon DynamoDb error in basic action

Edit: Try chaning

-keep publicclass com.example.myclass

to

-keep publicclasscom.example.myclass {
    *;
}