public class SqsBatchHandler implements RequestHandler<SQSEvent, SQSBatchResponse> {
    private final BatchMessageHandler<SQSEvent, SQSBatchResponse> handler;

    public SqsBatchHandler() {
        handler = new BatchMessageHandlerBuilder()
                .withSqsBatchHandler()
                .buildWithRawMessageHandler(this::processMessage);
    }

    @Override
    public SQSBatchResponse handleRequest(SQSEvent sqsEvent, Context context) {
        return handler.processBatch(sqsEvent, context);
    }

    private void processMessage(SQSEvent.SQSMessage sqsMessage) {
        LargeMessages.processLargeMessage(sqsMessage, this::handleProcessedMessage);
    }

    private void handleProcessedMessage(SQSEvent.SQSMessage processedMessage) {
        // processedMessage.getBody() will contain the content of the S3 Object
        // do something with the message
    }
}

public void handleRequest(SQSEvent event, Context context) {
    event.getRecords().forEach(message ->
        LargeMessages.processLargeMessage(message, processedMsg -> processMessage(processedMsg, context))
    );
}