如何继续制作 in - BlueJ Java 文件管理器

Question

我知道这有点菜鸟程序，但我慢慢地感到困惑。 'down' 函数将像 cd 一样工作，而 'up' 函数将像 cd 一样工作..

我不知道如何允许用户创建文件或文件夹。我尝试使用 arrayLists 而不是数组，但无法解决错误。任何帮助将不胜感激。

    import java.util.Scanner;
    class FileManager {
    //array of arrays will go here
    String Dir[] = {"UserOne"};
    String SystemFolders [] = {"Documents","","",};
    String SubFiles [] = {"","","","","",""};
    String Nav [][] = { Dir, SystemFolders, SubFiles};
    int levelCounter = 0;
    public void main(String[]args)   {
        Scanner sc = new Scanner (System.in);
        System.out.println("Enter a command");
        String command = sc.next();
            if (command.compareTo("down") == 0)
                down();
            //else if is on the way
    }
    void down ()    {
        //This will execute when the command is 'down'
        System.out.println(Nav[++levelCounter]);
    }
    void up ()  {
        //This will execute when the command is 'up'. It acts like cd..
        System.out.println(Nav[--levelCounter]);
    }
}

Answer 1

如果这是您程序的入口点，那么您需要将 main 方法声明为静态方法，例如

public static void main(String[] args)

然后要在主方法中访问 FileManager class 中的方法，您需要在主方法中创建 class 的实例。像这样

public static void main(String[]args)   {
    FileManager fm = new FileManager();  // Creates an instance
    Scanner sc = new Scanner (System.in);
    System.out.println("Enter a command");
    String command = sc.next();
    if (command.equals("down")) // equals will suffice in this case
                                // or equalsIgnoreCase() if you dont want case to be a problem
        fm.down(); // Notice now this calls the down method from the instance
    //else if is on the way
}

然后看这个例子create files or this to create folders

如何继续制作 in - BlueJ Java 文件管理器

How to proceed with making an in - BlueJ Java file manager

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