@Test
  public void hasAlertListenerIsTrueOnlyForLevelError() {
    alertingService.addAlertListener(member, ERROR);

    for (AlertLevel alertLevel : AlertLevel.values()) {
      if (alertLevel != ERROR) {
        assertThat(alertingService.hasAlertListener(member, alertLevel)).isFalse();
      }
    }
  }
Integration tests for adding and removing {@code Alert} listeners.
geode-log4j/src/integrationTest/java/org/apache/geode/alerting/log4j/internal/impl/AlertListenerRegistrationIntegrationTest.java