@Override
	public boolean add(V v) {
		return null == map.put(this.uniqueGenerator.apply(v), v);
	}
@Test
	public void addTest(){
		Set<UniqueTestBean> set = new UniqueKeySet<>(UniqueTestBean::getId);
		set.add(new UniqueTestBean("id1", "张三", "地球"));
		set.add(new UniqueTestBean("id2", "李四", "火星"));
		// id重复，替换之前的元素
		set.add(new UniqueTestBean("id2", "王五", "木星"));

		// 后两个ID重复
		assertEquals(2, set.size());
	}