I don't think you can find it anywhere. From
https://aws.amazon.com/blogs/aws/aws-lambda-update-run-java-code-in-response-to-events/
We provide you with two libraries specific to Lambda: aws-lambda-java-core with interfaces for Lambda function handlers and the context object, and aws-lambda-java-events containing type definitions for AWS event sources (Amazon Simple Storage Service (S3), Amazon Simple Notification Service (SNS), Amazon DynamoDB, Amazon Kinesis, and Amazon Cognito)
But in that page, you can find an alternative approach.
If you do not want to use POJOs or if Lambda’s serialization model does not meet your needs, you can use the Stream model. This is a bit lower-level:
public void lambdaHandler(InputStream input, OutputStream output, Context context)
throws IOException;
EDIT: I was also in need to use an SES Event inside a Lambda function, so I created my own class. It turns out the event has an object with name "Records" (with capital R). Capitalised fields are not OK in POJOs. And you cannot use annotations. In fact in this gist, you can find the Event, and two examples: WorkingCheckUser works, but NonWorkingCheckUser doesn't.