AWS Lambda now supports using a custom serializer with Java runtimes
AWS Lambda now supports replacing the default Java object serialization library with a customer-defined serializer. This feature is supported in all current Lambda managed runtimes and container base images for Java.
The ability to replace the default Java serializer enables customers to adapt their Lambda functions to cases where the incoming event format is not compatible with the default Lambda serializer. For example, to map a JSON event object whose properties are not in camel case such as 'vehicle-type' to a standard camel-cased field in a Java object.
This feature is available in all commercial AWS Regions where Lambda is supported, the AWS GovCloud (US) Regions, and the China Regions.
For more information, and to get started, see the Lambda documentation.