Question

我收到以下错误：

第13行，找不到符号--System.out.println（getDirection（room1））; （带箭头指向room1）。符号：可变空间1 地点：ArtRecord课程。

基本上代码尝试的是，转到getDirection的方法。并获取setDirection中设置的room1的方向。

import java.util.Scanner;
class ArtRecord
{
    public static void main (String[] param)
    {
        Scanner reader = new Scanner(System.in);

        createandprintsart();
        String location = askwhere();
        if (location == "Room 1"){
            System.out.println(getDirection(room1)); //#ERROR FOUND ON THIS LINE
        }
    }

    public static void createandprintsart()
    {
        Art room1 = new Art();
        Art room2 = new Art();
        Art room3 = new Art();
        Art room4 = new Art();

        //System.out.println(getDirection(room2));
        room1 = setDirection(room1, "To your left is a painting by");
        room2 = setDirection(room2, "Ahead of you is a painting by");
    }

    public static String askwhere()
    {
    Scanner reader = new Scanner(System.in);
    System.out.println("What room are you in?");
    System.out.println("Room 1");
    System.out.println("Room 2");
    System.out.println("Room 3");
    System.out.println("Room 4");
    String locationvalue = reader.nextLine();
    return locationvalue;
    }

    public static void doStuff(Art room)
    {

    }


    public static Art setDirection(Art room, String direction)

    {
        room.direction=direction;
        return room;
    }    

    public static String getDirection(Art room)

    {
        return room.direction;
    }

}

class Art
{
    String direction;
    String artist;
    String title;
    int year;
    int height;
    int width;

}

由于

Answer 1

room1被定义为createandprintsart()中的局部变量。因此，无法从main函数访问它。相反，你可以制作房间static实例变量吗？

另请注意，您不应将字符串与==进行比较，而应与String.equals(String str)进行比较。

Answer 2

有几件事。您正试图访问函数room1范围内不存在的对象main()。因此必须在类范围中声明Art类对象。其次，Art类对象也必须是静态的，才能从main函数访问。

最后，您无法使用==运算符比较java中的字符串。您必须使用.equals，并且还可以通过将每个函数移动到课程分数来避免为其创建scanner个对象。

class ArtRecord {

    static Art room1;
    static Art room2;
    static Art room3;
    static Art room4;
    static Scanner reader = new Scanner(System.in);

    public static void main(String[] param) {
        String next = reader.next();

        createandprintsart();
        String location = askwhere();
        if (location.equals("Room 1")) {
            System.out.println(getDirection(room1)); //#ERROR FOUND ON THIS LINE
        }
    }

    public static void createandprintsart() {
        room1 = new Art();
        room2 = new Art();
        room3 = new Art();
        room4 = new Art();

        //System.out.println(getDirection(room2));
        room1 = setDirection(room1, "To your left is a painting by");
        room2 = setDirection(room2, "Ahead of you is a painting by");
    }
    ...
}

Getter / Setter方法错误。找不到标志

2 个答案: