@Test
    public void isEmpty() throws Exception {
        ProviderGroup pg = null;
        Assert.assertTrue(ProviderHelper.isEmpty(pg));

        pg = new ProviderGroup("xxx", null);
        Assert.assertTrue(ProviderHelper.isEmpty(pg));

        pg = new ProviderGroup("xxx", new ArrayList<ProviderInfo>());
        Assert.assertTrue(ProviderHelper.isEmpty(pg));

        pg.add(ProviderHelper.toProviderInfo("127.0.0.1:12200"));
        Assert.assertFalse(ProviderHelper.isEmpty(pg));
    }
@author <a href="mailto:zhanggeng.zg@antfin.com">GengZhang</a>
core/api/src/test/java/com/alipay/sofa/rpc/client/ProviderHelperTest.java