minor improvement: missing with exercise principalprovider
@@ -39,6 +39,7 @@ class CustomPrincipalProvider implements PrincipalProvider {
this.knownPrincipalNames = ImmutableSet.copyOf(knownPrincipalNames);
}
+ @Nullable
@Override
public Principal getPrincipal(@NotNull String principalName) {
// EXERCISE: complete
