Java集合排序

	@Test
	void contextLoads() {

		List<User> dataList = new ArrayList<>();
		dataList.add(new User("3", "user", "pwd", "3"));
		dataList.add(new User("3", "user", "pwd", "1"));
		dataList.add(new User("3", "user", "pwd", "2"));
		dataList.add(new User("1", "user", "pwd", "9"));

		/**
		 * 默认升序
		 */
		dataList = dataList.stream().sorted(Comparator.comparing(User::getId)).collect(Collectors.toList());
		dataList.forEach(System.err::println);

		/**
		 * id 降序 order 降序
		 */

		dataList = dataList.stream().sorted(Comparator.comparing(User::getId).thenComparing(User::getOrder))
				.collect(Collectors.toList());
		System.out.println("-------------------- id 升序 order 升序-----------------------");

		dataList.forEach(System.err::println);
		/**
		 * id 降序 order 升序
		 */
		dataList = dataList.stream()
				.sorted(Comparator.comparing(User::getId, Comparator.reverseOrder()).thenComparing(User::getOrder))
				.collect(Collectors.toList());
		dataList.forEach(System.err::println);

	}