@SuppressWarnings("unchecked")
	public static <K, V> Map<K, V> fieldValueMap(Iterator<V> iter, String fieldName) {
		return toMap(iter, new HashMap<>(), (value) -> (K) ReflectUtil.getFieldValue(value, fieldName));
	}
@Test
	public void fieldValueMapTest() {
		final ArrayList<Car> carList = CollUtil.newArrayList(new Car("123", "大众"), new Car("345", "奔驰"), new Car("567", "路虎"));
		final Map<String, Car> carNameMap = IterUtil.fieldValueMap(carList.iterator(), "carNumber");

		assertEquals("大众", carNameMap.get("123").getCarName());
		assertEquals("奔驰", carNameMap.get("345").getCarName());
		assertEquals("路虎", carNameMap.get("567").getCarName());
	}