NoSuchElement由于Stream被关闭而被删除，但流从未关闭

Question

我遇到了抛出 NoSuchElementException 的问题。它被抛出，因为流已关闭，但我从未关闭流。问题发生在int selection = in.nextInt()的代码的早期。我一直试图纠正这个问题几个小时没有运气。任何帮助将非常感激。谢谢！

import java.util.Scanner;
    public class LoadMenu {
        private Menu main = new Menu();
        private EditMenu editSong = null;

        public LoadMenu(Menu menu) {
            main = menu;
    }

    private LoadMenu() {

    }

    public PlayList loadListMenu(PlayList list) throws Exception {
        Scanner in = new Scanner(System.in);
        int remove, edit;

        System.out.println("What would you like to do?");
        System.out.println();
        System.out.println("(1) Add Songs");
        System.out.println("(2) Remove Song");
        System.out.println("(3) Edit Song");
        System.out.println("(4) View Playlist");
        System.out.println("(5) Clear Playlist");
        System.out.println("(6) Save Playlist");
        System.out.println("(7) Main Menu");
        System.out.println("(8) Exit");
        System.out.println();

        System.out.print("Please make a selection: ");
        System.out.println(System.in.available());
        int selection = in.nextInt();
        System.out.println();

        if (selection == 1) {
            int num;

        System.out.print("How many songs would you like to add to " + list.getName() + ": ");
        num = in.nextInt();
        System.out.println();

        if (num > 1) {
            for (int i = 0; i < num; i++) {
                Function newSong = new Function(list);
                System.out.println("Enter information for song " + (i + 1) + ":");
                Song addSong = newSong.newSong();
                list.addSong(addSong);
                System.out.println();
            }
            this.loadListMenu(list);
        } else {
            Function newSong = new Function(list);
            Song addSong = newSong.newSong();

            list.addSong(addSong);
            this.loadListMenu(list);
        }
    } else if (selection == 2) {

        System.out.println("Which song would you like to remove?");
        for (int i = 0; i < list.numSongs(); i++) {
            System.out.println(
                    "(" + (i + 1) + ") " + list.getSong(i).getTitle() + " by " + list.getSong(i).getArtist());
        }

        System.out.println();
        System.out.print("Song number to remove: ");
        remove = in.nextInt();

        list.removeSong(remove - 1);

        this.loadListMenu(list);
    } else if (selection == 3) {

        System.out.print("Which song would you like to edit?");
        System.out.println();

        if (list.numSongs() == 0) {
            System.out.println("There are no songs saved in " + list.getName());
        } else {
            for (int i = 0; i < list.numSongs(); i++) {
                System.out.println(
                        "(" + (i + 1) + ") " + list.getSong(i).getTitle() + " by " + list.getSong(i).getArtist());
            }

            System.out.println();
            System.out.print("Make a selection: ");
            edit = in.nextInt();
            System.out.println();

            editSong = new EditMenu(list, edit);
            list = editSong.editSong();
        }

        this.loadListMenu(list);

    } else if (selection == 4) {

        if (list.numSongs() == 0) {
            System.out.println("There are no songs saved in " + list.getName());
        }
        for (int i = 0; i < list.numSongs(); i++) {
            System.out.println(
                    "(" + (i + 1) + ") " + list.getSong(i).getTitle() + " by " + list.getSong(i).getArtist());
        }

        System.out.println();

        this.loadListMenu(list);

    } else if (selection == 5) {
        list.clearList();

        this.loadListMenu(list);
    } else if (selection == 6) {
        PlayListWrite saveFile = new PlayListWrite(list);
        saveFile.saveFile();

        this.loadListMenu(list);

    } else if (selection == 7) {
        main.mainMenu(list);
    } else if (selection == 8) {
        System.exit(0);
    }
    return list;
}

}