    @Test
    public void testAddAll() {

        TagSet raw = new TagSet(new TreeMap<String, Tag>());
        TagSet ts1 = raw.add(new BasicTag("k1", "k1")).addAll(new Tag[] {})
            .addAll(new ArrayList<Tag>()).addAll(new HashMap<String, String>());
        System.out.println(ts1);
        Assert.assertEquals("[k1=k1]", ts1.toString());
        Tag tag1 = new BasicTag("k1", "v1");
        Tag tag2 = new BasicTag("k2", "v2");
        Tag tag3 = new BasicTag("k3", "v3");
        Map<String, String> map = Maps.newTreeMap();
        map.put("k3", "v33");
        map.put("k4", "v4");
        TagSet ts2 = raw.addAll(new Tag[] { tag1, tag2 })
            .addAll(Lists.<Tag> newArrayList(tag2, tag3)).addAll(map);
        System.out.println(ts2.toString());
        Assert.assertEquals("[k1=v1, k2=v2, k3=v33, k4=v4]", ts2.toString());

    }