使用Java扫描仪时如何检查\n？

Question

我正在尝试编写一个扫描器，以便每次\n被检测到，它会扫描那之后的行，直到一个新的\n出现。我第一次试过这样的东西。

import java.util.Scanner;

public class test{
    
    public static void main(String[] args) {
        
        String input = "first line \nsecond line \nthird line";
        
        Scanner sc = new Scanner(input);
        
        while(sc.hasNextLine()) {
            String stuff = sc.nextLine();
            System.out.println(stuff);
        }
        sc.close();
    }
}

它起作用，输出为

first line 
second line 
third line

然而，当我尝试用扫描器（System.in）做同样的事情时，即使输入相同，它也不能以同样的方式工作

import java.util.Scanner;

public class test{
    
    public static void main(String[] args) {
        System.out.println("Please enter things");
        
        Scanner cmd = new Scanner(System.in); //input: "first \n second \n third"
        
        String input = cmd.nextLine();
        
        Scanner sc = new Scanner(input);
        
        while(sc.hasNextLine()) {
            String stuff = sc.nextLine();
            System.out.println(stuff);
        }
        cmd.close();
        sc.close();
    }
}

输出：

first \n second \n third

编辑：如果输入为

first
second
third

并立即输入提示符,那么Scanner.nextLine（）是否就足够了？

Answer 1

System.out.println("Please enter things");
    Scanner cmd = new Scanner(System.in); //input: "first \n second \n third"
    
    while(cmd.hasNext()) {
        String word = cmd.next();
        if(word.equals("\\n")) {
            System.out.println();
        }else {
            System.out.print(word);
            
        }
    }