public Set<String> getPrimaryIdentifiers() {
        return primaryIdentifiers;
    }
Gets a set of identifier names that represent the primary way to identify
a CloudFormation resource. This uniquely identifies an individual instance
of the resource type, and can be one or more properties to represent
composite-key identifiers.

@return Returns the identifier set primarily used to access a
  CloudFormation resource.
smithy-aws-cloudformation-traits/src/main/java/software/amazon/smithy/aws/cloudformation/traits/CfnResource.java