public String doLayout(ILoggingEvent event) {
        if (!isStarted()) {
            return CoreConstants.EMPTY_STRING;
        }
        return writeLoopOnConverters(event);
    }
@Test
    public void cnTest() {
        pl.setPattern("%cn");
        loggerContext.setName("aValue");
        pl.start();
        String val = pl.doLayout(getEventObject());
        assertEquals("aValue", val);
    }