Java System Properties - aws.accessKeyId and aws.secretAccessKey

Environment Variables - AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY

Credential profiles file at the default location (~/.aws/credentials) shared by all AWS SDKs and the AWS CLI

Credentials delivered through the Amazon ECS if the AWS_CONTAINER_CREDENTIALS_RELATIVE_URI environment variable is set and the security manager has permission to access the variable,

Instance profile credentials delivered through the Amazon EC2 metadata service