Setter 和 getter 不起作用

Question

这是我关于 setter 和 getter 的任务，由于某种原因它不起作用。谁能检查一下我的问题是什么？谢谢你。

public class FlightTest
{
    public static void main (String [] args)
    {

        String name;
        String number;
        String Orig;
        String Desti;

        Scanner scan = new Scanner (System.in);

        Flight data = new Flight ();

        System.out.print ("Airline Name: ");
        String AirlineName = scan.nextLine ();
        data.setAirlineName (name);

        System.out.print ("Flight Number: ");
        String FlightNumber = scan.nextLine ();
        data.setFlightNumber (number);

        System.out.print ("Origin: ");
        String Origin = scan.nextLine();
        data.setOrigin (Orig);

        System.out.print ("Destination: ");
        String Destination = scan.nextLine ();
        data.setDestination (Desti);

        System.out.println (data);
    }   
}





public class Flight

{

    private String AirlineName;

    private String FlightNumber;

    private String Origin;

    private String Destination;

    public String setAirlineName()
    {
        String Name = AirlineName;
        return Name;
    }

    public Flight ()
    {
        AirlineName = "";
        FlightNumber = "";
        Origin = "";
        Destination = "";
    }

    public String getAirlineName()
    {
        return AirlineName;
    }

    public void setAirlineName (String name)
    {
        AirlineName = name;
    }

    public String getFlightNumber ()
    {
        return FlightNumber;
    }

    public void setFlightNumber (String number)
    {
        FlightNumber = number;
    }

    public String getOrigin ()
    {
        return Origin;
    }

    public void setOrigin (String Orig)
    {
        Origin = Orig;
    }

    public String getDestination ()
    {
        return Destination;
    }

    public void setDestination (String Desti)
    {
        Destination = Desti;
    }

    public String toString ()
    {
        String result = AirlineName + " flight number " + FlightNumber + " leaves from " + Origin + " to " + Destination + ".";
        return result;
    }
}

Answer 1

这是问题所在：

    String AirlineName = scan.nextLine ();
    data.setAirlineName (name);

您正在读取一个名称并将其放入AirlineName，然后使用不同的变量作为参数调用 setter 。

事实上，你应该得到一个编译错误，告诉你name没有初始化。

您还有第二个（虚假的） setAirlineName 方法，如下所示：

public String setAirlineName()
{
    String Name = AirlineName;
    return Name;
}

...这不是一个合适的二传手。但看起来你的main方法没有调用它，所以这不是你的问题的原因。（您正在调用setAttributeName(String)重载...）

最后，拜托，拜托，拜托，学习遵循标准的 Java 风格的标识符约定。变量或属性名称应该不以大写字母开头。将您的AirlineName属性和变量更改为airlineName，等等。