Question

很难在主要方法中调用方法。一直说它找不到符号 - 方法addSales（double）

我正在做一个编程项目，因为我们刚刚学习了继承，它有3个超类和3个子类。我遇到了一个子课和超级课的问题。他们被命名为Hourly and Commission。佣金每小时延长一次。我觉得我已经正确地编写了名为addSales的方法，但是当我在main中调用它时它说它找不到方法。我在这里错过了什么吗？任何帮助将不胜感激。

佣金等级：

public class Commission extends Hourly
{
private double totalSales, commission;

public Commission(String eName, String eAddress, String ePhone,
String socSecNumber, double rate, double commissionRate)
{
    super(eName, eAddress, ePhone, socSecNumber, rate);
    totalSales = 0.0;
    commission = commissionRate;
}

public double pay()
{
    double payment = super.pay();
    payment = (payment + (commission * totalSales));
    return payment;
}
public String toString()
{
    String result = super.toString();
    result += "Total Sales: " + totalSales;

    return result;

}
public void addSales(double totalS)
{
    totalSales = totalSales + totalS;
}
}

每小时课程：

public class Hourly extends Employee
{
private int hoursWorked;

//-----------------------------------------------------------------
//  Sets up this hourly employee using the specified information.
//-----------------------------------------------------------------
public Hourly (String eName, String eAddress, String ePhone,
String socSecNumber, double rate)
{
    super (eName, eAddress, ePhone, socSecNumber, rate);

    hoursWorked = 0;
}

//-----------------------------------------------------------------
//  Adds the specified number of hours to this employee's
//  accumulated hours.
//-----------------------------------------------------------------
public void addHours (int moreHours)
{
    hoursWorked += moreHours;
}

//-----------------------------------------------------------------
//  Computes and returns the pay for this hourly employee.
//-----------------------------------------------------------------
public double pay()
{
    double payment = payRate * hoursWorked;

    hoursWorked = 0;

    return payment;
}

//-----------------------------------------------------------------
//  Returns information about this hourly employee as a string.
//-----------------------------------------------------------------
public String toString()
{
    String result = super.toString();

    result += "\nCurrent hours: " + hoursWorked;

    return result;
}
}

主：

public class Firm
{
//--------------------------------------------------------------
//  Creates a staff of employees for a firm and pays them.
//--------------------------------------------------------------
public static void main (String[] args)
{
    Staff personnel = new Staff(8);

    Executive staff0 = new Executive ("Sam", "123 Main Line", "555-0469", "123-45- 6789", 2423.07);
    StaffMember staff1 = new Employee ("Carla", "456 Off Line", "555-0101", "987-65-4321", 1246.15);
    StaffMember staff2 = new Employee ("Woody", "789 Off Rocker", "555-0000", "010-20-3040", 1169.23);

    Hourly staff3 = new Hourly ("Diane", "678 Fifth Ave.", "555-0690", "958-47-3625", 10.55);

    Hourly staff6 = new Commission("Marcus Gendron", "66 Highland St.", "272-9555", "123-62-5678", 6.25, 0.20);
    Hourly staff7 = new Commission("Joe Dangerous", "55 dude Court", "555-1267", "777-66-5555", 9.75, 0.15);

    StaffMember staff4 = new Volunteer ("Norm", "987 Suds Blvd.", "555-8374") ;
    StaffMember staff5 = new Volunteer ("Cliff", "321 Duds Lane", "555-7282");



    personnel.addStaff(staff0);
    personnel.addStaff(staff1);
    personnel.addStaff(staff2);
    personnel.addStaff(staff3);
    personnel.addStaff(staff4);
    personnel.addStaff(staff5);
    personnel.addStaff(staff6);
    personnel.addStaff(staff7);





    staff6.addHours(35);
    staff6.addSales(400.0);

     //error is being shown here ^^^^


    staff7.addHours(40);
    staff7.addSales(950.00);
    staff0.awardBonus (500.00);
    staff3.addHours (40);
    personnel.payday();
}
}

Answer 1

staff6和staff7都是Hourly的实例。 Hourly类没有附加特定方法。

您必须将它们声明为Commission的具体实例。

Answer 2

staff6被声明为Hourly，即使它实际上是Commission，您也试图访问超类'方法。

将其声明为Commission。

Answer 3

我在下面看到了对象创建：

 Hourly staff6 = new Commission("Marcus Gendron", "66 Highland St.", "272-9555", "123-62-5678", 6.25, 0.20);

addSales方法在子类委员会中。但是staff6的类型是Hourly，它是父类，而Hourly类没有这个方法。你没有看到方法addsales。

有关更详细的理解，请尝试以下行（编译正常）。看看你得到的所有方法

Object staff6 = new Commission("Marcus Gendron", "66 Highland St.", "272-9555", "123-62-5678", 6.25, 0.20);

Answer 4

此处您只能调用每小时课程中出现的方法。

因为您现在将Hourly类引用为每小时类中不存在的addSales，所以它无法访问。

 Hourly staff6 = new Commission("Marcus Gendron", "66 Highland St.", "272-9555", "123-62-5678", 6.25, 0.20);

在上面的代码中，Commission类对象引用了Hourly类。所以委员会对象只允许访问那些属于Hourly类的方法（因为它们是继承的），并且在委托类中重写了每小时类的方法。

找不到符号 - 方法

4 个答案: