ential validation AND providing groups.
 <p>
 Implementations of this API should not return a direct reference
 to a <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Set.html?is-external=true" title="class or interface in java.util" class="externalLink"><code>Set</code></a> used internally to represent an <a href="IdentityStore.html" title="interface in jakarta.security.enterprise.identitystore"><code>IdentityStore</code></a>'s validation types,
 unless it is an immutable <a h