public Terra(String Sign, int ID, int StreetID)
    {
        this.sign = Sign;
        this.id = ID;
        this.streetID = StreetID;
        this.grade = 0;
        this.owner = null;
        switch (StreetID)
        {
            case 0:
                this.value = -1;
            case 1:
            case 2:
                this.value = 200;
                break;
            case 3:
                this.value = 500;
                break;
            case 4:
            case 5:
                this.value = 300;
                break;
            default:
                System.out.print("没有此地段号");
        }
    }