The Decrypted AttributeDefinition decrypts values of input attributes to an output attribute. The encryption/decryption is based on a supplied utility class used elsewhere in the IdP called a DataSealer.
This is a utility component that may prove useful in support of use cases where data being resolved should be private to the IdP but stored elsewhere.
This may be wired up globally or in an additional resource local to the AttributeResolverConfiguration. Typically the component built-in to the IdP for use in client session management is not suitable because that key is designed to change frequently.