To load files on startup with AWS S3 and Spring Boot, you'll need the aws-java-sdk-core dependency in your pom.xml file.
Your application.yml file should contain the name of your S3 bucket, which can be accessed through the ConfigProperties class.
The FontService class is responsible for initializing the AmazonS3 object, creating a directory for downloaded files, getting a list of file keys in the bucket, and creating font files from the received byte arrays.
By updating your AWS credentials file and starting the Spring Boot application, the files from the S3 bucket will be downloaded and stored in the specified directory.