使用LinkedList集合模拟点歌系统

package com.czie.iot1913.lps;

import java.util.LinkedList;
import java.util.Scanner;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 21:16
 */
public class KTVByArrayList {
    public static void main(String[] args) {
        System.out.println("------------欢迎来到品水KTV点歌系统------------");
        System.out.println("0-添加歌曲到列表哈");
        System.out.println("1-将此歌曲置顶");
        System.out.println("2-将歌曲提前一位");
        System.out.println("3-退出");
        LinkedList<Object> lineUplist = new LinkedList<>();
        addMusicList(lineUplist);//显示默认歌单
        while (true){
            System.out.println("请输入您的指令序号！！！");
            Scanner sc = new Scanner(System.in);
            int command=sc.nextInt();
            switch (command){
                case 0:
                    addMusic(lineUplist);
                    break;
                case 1:
                    setTop(lineUplist);
                    break;
                case 2:
                    setBefore(lineUplist);
                    break;
                case 3:
                    exit();
                    break;
                default:
                    System.out.println("============================");
                    System.out.println("命令输入有错误,请重新输入");
                    break;
            }
            System.out.println("当前列表"+lineUplist);

        }


    }
    //初始化歌曲列表
    private static void addMusicList(LinkedList lineUpList){
        lineUpList.add("稻香");
        lineUpList.add("追梦赤子心");
        lineUpList.add("See you again");
        lineUpList.add("白羊");
        lineUpList.add("c u again");
        System.out.println("初始歌曲列表为"+lineUpList);
    }
    //添加歌曲
    private static void addMusic(LinkedList lineUpList){
        System.out.println("请输入要添加的歌名：");
        String musicName = new Scanner(System.in).nextLine();
        lineUpList.add(musicName);//添加歌曲
        System.out.println("已添加歌曲"+musicName);
    }
    //将此歌曲置顶
    public static void setTop(LinkedList lineUpList){
        System.out.println("请输入需要置顶的歌曲名称：");
        String musicName = new Scanner(System.in).nextLine();
        int position=lineUpList.indexOf(musicName);
        if (position<0){
            System.out.println("当前列表没有这首歌");
        }else {
            lineUpList.remove(musicName);
            lineUpList.addFirst(musicName);
        }
        System.out.println("已经将歌曲"+musicName+"置顶成功");
    }
    //将歌曲置前一位
    private static void setBefore(LinkedList lineUpList){
        System.out.println("请输入你需要前移的歌曲名称：");
        String musicName = new Scanner(System.in).nextLine();
        int position=lineUpList.indexOf(musicName);
        if (position<0){
            System.out.println("当前列表没有这首歌");
        }else if(position==0){
            System.out.println("这首歌已经置顶");
        }else {
            lineUpList.remove(musicName);
            lineUpList.add(position-1,musicName);
        }
        System.out.println("前移的歌曲"+musicName+"成功");
    }
    private static void exit(){
        System.out.println("------------退出------------");
        System.out.println("您已经退出系统");
        System.exit(0);
    }
}