@Test
    public void size() throws Exception {
        ProviderGroup pg = new ProviderGroup("xxx", null);
        Assert.assertTrue(pg.size() == 0);

        pg = new ProviderGroup("xxx", new ArrayList<ProviderInfo>());
        Assert.assertTrue(pg.size() == 0);

        pg = new ProviderGroup("xxx", Arrays.asList(ProviderHelper.toProviderInfo("127.0.0.1:12200")));
        Assert.assertTrue(pg.size() == 1);
    }
@author <a href="mailto:zhanggeng.zg@antfin.com">GengZhang</a>
core/api/src/test/java/com/alipay/sofa/rpc/client/ProviderGroupTest.java