@Test
public void testGetLabels() {

    Labels labels = new Labels();
    labels.set("k1", "v1");
    labels.set("k2", "v2");
    labels.set("k3", "v3");
    labels.set("k3", "v4");
    StringBuilder sb=new StringBuilder();
    labels.getLabels().stream().forEach(x->sb.append(x.toString()));
    System.out.println(sb.toString());
    Assert.assertEquals("k1=v1k2=v2k3=v3",sb.toString());
}