Error: DynamoDB Mapper Could Not Instantiate Class
Answered by Rafal Wilinski
What's Causing This Error
When working with DynamoDB Mapper, if the program is trying to map an object to a DynamoDB table but cannot instantiate the class that represents the object, then this error can arise. Alternatively, it may be because the class you're trying to map to the DynamoDB table has a constructor with parameters.
Solution: Here's How To Resolve It
To resolve this error, check and verify that the class has a default constructor and is on the classpath. In addition, if the class you are trying to map to the DynamoDB table has a constructor with parameters, you have to use DynamoDBMapperConfig.Builder.withSaveBehavior(DynamoDBMapperConfig.SaveBehavior.UPDATE_SKIP_NULL_ATTRIBUTES).
Ensure that the class is available on the classpath along with all its dependencies, and ensure the class has correct annotations and they are in the right package.
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