public WeightRandom() {
		weightMap = new TreeMap<>();

	}
@Test
	public void weightRandomTest() {
		WeightRandom<String> random = WeightRandom.create();
		random.add("A", 10);
		random.add("B", 50);
		random.add("C", 100);

		String result = random.next();
		assertTrue(CollUtil.newArrayList("A", "B", "C").contains(result));
	}