@CheckForNull
  public String getExternalUserAuthentication() {
    SecurityRealm realm = securityRealmFactory.getRealm();
    return realm == null ? null : realm.getName();
  }
@Test
  public void getExternalUserAuthentication_whenDefined_shouldReturnName() {
    mockSecurityRealmFactory("Security Realm");

    assertThat(commonSystemInformation.getExternalUserAuthentication())
      .isEqualTo("Security Realm");
  }