assertEquals(1, events.size());
        assertEquals("FATAL", events.get(0).getLevel());
    }

    @Test
    public void test_append_multipleEvents() {
        appender.append(createLogEvent(Level.ERROR, "org.codelibs.fess.a", "error 1"));
        appender.append(createLogEvent(Level.ERROR, "org.codelibs.fess.b", "error 2"));