错误:类中的私有访问

Question

public class ProductionWorker extends Employee
{
    private int shift;
    private double rateOfPay;
    private double hoursWorked;

    ProductionWorker(String name, int id, int shift, double rateOfPay, double hoursWorked)
    {
        super(name, id);
        this.shift = shift;
        this.rateOfPay = rateOfPay;
        this.hoursWorked = hoursWorked;
    }



public class TeamLeader extends ProductionWorker
{
    private double monthlyBonus;

    TeamLeader(String name,int id, int shift, double rateOfPay, double hoursWorked, double monthlyBonus)
    {
        super(name, id , shift, rateOfPay, hoursWorked);
        this.monthlyBonus = monthlyBonus;

    }

    public double calcPay()
    {
        double pay = 0;
        //night shift
        if (shift == 2)
        {
            pay = ((hoursWorked + hoursWorked / 2) * rateOfPay) + monthlyBonus;
        }
        else
        {
            pay = (hoursWorked * rateOfPay) + monthlyBonus;
        }
        return pay;
    }
}

我将类ProductionWorker扩展到类TeamLeader，然后在类TeamLeader上创建了一个方法calcPay()我的问题是，我需要从类ProductionWorker中获取变量shift，hoursOfWorked和rateOfPay的值，这样我就可以使用calcPay()方法来执行我的main.Can了，有人能帮我吗，提前谢谢。

Answer 1

要访问父类(ProductionWorker)的变量，需要将变量范围从private更改为protected。

私有变量仅在类中可见。受保护的变量在子类中可见，对包中的所有类都可见

你可以参考这个链接：http://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html。

如果您不希望将它们设置为受保护，也可以为变量创建getter和setter，但这不是首选方法。

例如getter和setter：

private int shift;

protected int getShift() {
    return this.shift;
}

protected void setShift(int shift) {
     this.shift = shift;
}