java8新特性记录

一、limit() 

List list = Arrays.asList(1,2,3,4,5,6,6,7,7,8,8,9,9);

List resultLimit = list.stream().limit(5).collect(Collectors.toList());
		System.out.println(resultLimit);

二、skip() 跳过元素

List list = Arrays.asList(1,2,3,4,5,6,6,7,7,8,8,9,9);
//skip跳过元素
List resultSk = list.stream().skip(5).collect(Collectors.toList());
		System.out.println(resultSk);

三、去除List中重复得Integer

List list = Arrays.asList(1,2,3,4,5,6,6,7,7,8,8);
result = list.Stream().distinct().collect(toList());
System.out.println(result);

四、去除List中重复的String

List uniqueStr = list.stream().distinct().collect(Collectors.toList());

五、所有的元素都乘2 i->i*2

//所有的元素都乘2 i->i*2
List list = Arrays.asList(1,2,3,4,5,6,6,7,7,8,8,9,9);
		
List result = list.stream().map(i -> i*2).collect(Collectors.toList());
System.out.println(result);

六、遍历

	public static  List userlist() {
		List list = Arrays.asList(
				new User("猫",2,"中华田园猫","橘黄色"),
				new User("狗",2,"泰迪","卷毛")
				);
		
		return list;
	}

userlist().stream().map(user -> user.getName()).forEach(System.out::println);
userlist().stream().map(user -> user).forEach(System.out::println);

List lists = userlist().stream().map(user -> user.getAge()).collect(Collectors.toList());
System.out.println(lists);

//猫 狗 2 2