list集合中快速取数据

在userList中取出age小于30岁的用户

	List<User> userList = new ArrayList<User>();
	User u1 = new User("张三",10);
	User u2 = new User("李四",20);
	User u3 = new User("王五",40);
	User u4 = new User("李六",50);
	userList.add(u1);
	userList.add(u2);
	userList.add(u3);
	userList.add(u4);
	System.out.println(userList);
    
	//从userList中取出age小于30岁的用户
	List<User> userList2 = userList.stream().filter(s -> s.getAge() < 30).collect(Collectors.toList());
	System.out.println(userList2);

输出结果