-2

我有一个看起来像这样的项目：

public interface Payable{
    double getPaymentAmount(); // calculate payment; no implementation
} // end interface Payable

然后我有一个像这样的抽象类：

    public abstract class Employee implements Payable
    {
       private String firstName;
       private String lastName;
       private String socialSecurityNumber;
       // three-argument constructor
       public Employee( String first, String last, String ssn )
       {
           firstName = first;
           lastName = last;
           socialSecurityNumber = ssn;
       } // end three-argument Employee constructor
       // set first name
       public void setFirstName( String first )
       {
          firstName = first; // should validate
       } // end method setFirstName
       // return first name
       public String getFirstName()
       {
          return firstName;
       } // end method getFirstName
       // set last name
       public void setLastName( String last )
       {
          lastName = last; // should validate
       } // end method setLastName
       // return last name
       public String getLastName()
       {
          return lastName;
       } // end method getLastName
       // set social security number
       public void setSocialSecurityNumber( String ssn )
       {
          socialSecurityNumber = ssn; // should validate
       } // end method setSocialSecurityNumber
       // return social security number
       public String getSocialSecurityNumber()
       {
          return socialSecurityNumber;
       } // end method getSocialSecurityNumber
       // return String representation of Employee object
       @Override
       public String toString()
       {
          return String.format( "%s %s\nsocial security number: %s",
          getFirstName(), getLastName(), getSocialSecurityNumber() );
       } // end method toString
// Note: We do not implement Payable method getPaymentAmount here so
// this class must be declared abstract to avoid a compilation error.
    } // end abstract class Employee
`

最后一个是这样的公共类继承 Employee ：

 *public class SalariedEmployee extends Employee*

以及此处的提示错误：
“错误：SalriedEmployee 不是抽象的，并且不会覆盖 Payable public class SalariedEmployee extends Employee 中的抽象方法 getPaymentAmount() ”

我不知道这是从哪里来的。这段代码取自一本书，应该很好。我正在使用 netbean 8.0 和 jdk 1.7

4

4 回答 4

1

您的错误代码说明了一切。您必须从您的 Interface 实现每个抽象方法Playable。getPaymentAmount()在这种情况下，您缺少SalariedEmployee类中的方法。

编辑：固定类

于 2015-03-26T13:06:41.357 回答
1

您必须getPaymentAmount()在您的抽象类（Employee）或您的抽象类中实现，SalariedEmployee因为它们实现Payable并且此类包含该功能getPaymentAmount()

于 2015-03-26T13:07:32.573 回答
0

好的，我解决了这个问题，只是因为我没有写这个文件的所有代码，他。所以基本上是我们写行的时候

public class SalariedEmployee extends Employee

只有我们编写所有代码并添加方法才会出现提示

public double getPaymentAmount()
{
return getWeeklySalary();
} // end method getPaymentAmount

到我们的程序然后错误就会消失。我得到它感谢支持。像这样的文件 SalariedEmployee.java 的 BTW 代码

public class SalariedEmployee extends Employee
{
private double weeklySalary;
// four-argument constructor
public SalariedEmployee( String first, String last, String ssn,double salary )
{
super( first, last, ssn ); // pass to Employee constructor
setWeeklySalary( salary ); // validate and store salary
} // end four-argument SalariedEmployee constructor
// set salary
public void setWeeklySalary( double salary )
{
if ( salary >= 0.0 ) weeklySalary = salary;
else
throw new IllegalArgumentException(
"Weekly salary must be >= 0.0" );
} // end method setWeeklySalary
// return salary
public double getWeeklySalary()
{
return weeklySalary;
} // end method getWeeklySalary

// calculate earnings; implement interface Payable method that was
// abstract in superclass Employee
@Override
public double getPaymentAmount()
{
return getWeeklySalary();
} // end method getPaymentAmount
@Override
public String toString()
{
return String.format( "salaried employee: %s\n%s: $%,.2f",
super.toString(), "weekly salary", getWeeklySalary() );
} // end method toString
} // end class SalariedEmployee
于 2015-03-26T13:23:49.600 回答
0

getPaymentAmount()您必须按照接口 ( ) 和抽象类定义的要求来实现每个方法。

于 2015-03-26T13:09:09.950 回答