Getter、Setter 和 NullPointerException-解网

问：

首先，我正在尝试为我本地初始化的数组分配值。数组的类类型存储在另一个类中，并且变量是私有的，因此我使用 getter 和 setter 来设置值。但它在房间显示“线程”main“java.lang.NullPointerException 中的异常。Test.main（Test.java：26）“，下面是我的 test.java 代码：

public class Test {

    public static void main(String[] args) {
        Room[] room = new Room[72];
        Integer i = 0;
        try {
            File RoomTxt = new File("Room.txt");
            Scanner read = new Scanner(RoomTxt);
            while (read.hasNextLine()) {
                room[i].setRoomID(read.next());
                room[i].setRoomType(read.next() + " " + read.next());
                room[i].setFloor(read.nextInt());
                room[i].setRoomStatus(read.nextInt());
                read.nextLine();
                i++;
            }
            read.close();
        } catch (FileNotFoundException e) {
            System.out.println("An error occurred.");
            e.printStackTrace();
        }
}

下面是我用来存储 Room 类型的类：

public class Room {

    private String roomID;
    private String roomType;
    private Integer floor;
    private Integer roomStatus;

    //Setter
    public void setRoomID(String roomID) {
        this.roomID = roomID;
    }

    public void setRoomType(String roomType) {
        this.roomType = roomType;
    }

    public void setFloor(Integer floor) {
        this.floor = floor;
    }

    public void setRoomStatus(Integer roomStatus) {
        this.roomStatus = roomStatus;
    }

    //Getter
    public String getRoomID() {
        return this.roomID;
    }

    public String getRoomType() {
        return this.roomType;
    }

    public Integer getFloor() {
        return this.floor;
    }

    public Integer getRoomStatus() {
        return this.roomStatus;
    }
}

存储在我的房间.txt中的记录就像

RS11 Single Room 1 1
RD12 Double Room 1 0

java 数组 nullpointerexception 私有 getter-setter

public class Test {

    public static void main(String[] args) {
        Room[] room = new Room[72];
        Integer i = 0;
        try {
            File RoomTxt = new File("Room.txt");
            Scanner read = new Scanner(RoomTxt);
            while (read.hasNextLine()) {
                room[I] = new Room();
                // set the field values
            }
            read.close();
        } catch (FileNotFoundException e) {
            // ...
        }
}

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