public boolean isAttached(Appender<E> appender) {
        if (appender == null) {
            return false;
        }
        for (Appender<E> a : appenderList) {
            if (a == appender)
                return true;
        }
        return false;
    }
@Test
    public void testIsAttached() throws Exception {
        NOPAppender<TestEvent> ta = new NOPAppender<TestEvent>();
        ta.start();
        aai.addAppender(ta);
        NOPAppender<TestEvent> tab = new NOPAppender<TestEvent>();
        tab.setName("test");
        tab.start();
        aai.addAppender(tab);
        Assertions.assertTrue(aai.isAttached(ta), "Appender is not attached");
        Assertions.assertTrue(aai.isAttached(tab), "Appender is not attached");
    }