Error: DynamoDB Mapper Could Not Instantiate Class
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.
Other Common DynamoDB Errors (with Solutions)
- dynamodb unable to locate property for key attribute
- ExpressionAttributeValues contains invalid value: One or more parameter values were invalid: An AttributeValue may not contain an empty string
- dynamodb cannot read properties of undefined
- aws.dynamodb.converter.unmarshall not working
- dynamodb mapper save not persisting
- dynamodb query not returning the full item
- dynamodb cannot assign requested address
- why is the GSI dynamodb not showing item count
- an expression attribute name used in the document path is not defined
- DynamoDB local error spawn java ENOENT
- DynamoDB missing items
- AWS CLI DynamoDB Error Parsing Parameter
- DynamoDB attribute not empty
- DynamoDB is missing the key id in the item
- Boto3 DynamoDB KeyError