乘以一个双值与两个短裤的分配结果

Question

我的程序的目的是显示员工（经理的编码）的工资，具体取决于该员工在一个月内工作了多少小时。该数组包含3个员工以会计师为参数。每位员工的会计回报。编码器和管理者的工资以不同的方式计算。

这里是我的Java代码：

public class OOP 
    { 
     public static void main(String[] args) 
     { 
    // fill the staff array with three Employee objects. 


    Employee[] staff = new Employee[3]; 

    staff[0] = new Manager("Carl Cracker",75000.00,(short)160); 
    staff[1] = new Coder("Harry Hacker", 50000.00,(short)165); 
    staff[2] = new Coder("Tony Tester", 40000.00,(short)200); 

    Accountant Counter = new Accountant(); 
    Counter.printSalary(staff, (byte)2); 

     } 
    } 

    abstract class Employee 
    { 
     public Employee(String n, double w, short h) 
    { 
     name = n; 

     wageRate = w; 

     workedHours = h; 

    } 

    public String getName() 
    { 
     return name; 
    } 

    public double getSalary(short workingHours) 
    { 

     this.salary = this.wageRate * (this.workedHours/workingHours); 
     return salary; 
    } 

    private String name; 
    protected double wageRate; 
    protected short workedHours; 
    protected double salary; 
    } 
    class Coder extends Employee 
    { 
     public Coder (String n, double w, short h) 
     { 
      super(n, w, h); 
     } 

     public double getSalary(short workingHours) 
     { 
      return super.getSalary(workingHours); 
     } 
    } 
    class Manager extends Employee 
    { 
     public Manager (String n, double w, short h) 
     { 
      super(n, w, h); 
     } 
     public double getSalary(short workingHours) 
     { 
      if (workingHours > workedHours) 
      return super.getSalary(workingHours)*0.7; 
      else 
       { 
        salary = wageRate; 
        return salary; 
       } 


     } 
    } 
    class Accountant 
    { 
     public Accountant() 
     { 
     } 
     public void printSalary(Employee[] emp, byte monthInd) 
     { 
      Employee[] workers = emp; 
      byte MID = monthInd; 
      MID = (byte) (MID - 1); 
      for (Employee worker : workers) 
       { 
        System.out.printf("%s's salary this month is %8.2f",worker.getName(), worker.getSalary(workingHours[MID])); 
        System.out.println(); 
       } 
     } 

     private short[] workingHours = new short[]{168,160,160,172,162,154,184,168,168,184,168,172}; 
    } 

预期结果：

卡尔饼干的这个月的工资是75000

哈利黑客这个月的工资为51562.5

托尼计的薪水此月是50000

实际值r esult：

卡尔饼干的这个月的工资是75000,00

哈利黑客这个月的工资是50000,00

托尼Tester的这个月的工资是40000,00

请能有人给我解释一下为什么？

Answer 1

你是Java中整数除法的受害者。

即使使用short值，integer division（JLS 15.17.2）也适用，其中非整数结果被截断。第二个月，索引1是160个工作小时。托尼测试员有200个小时。在正常的数学，160分之200= 1.25，但在Java整数除法，一百六十零分之二百= 1。这就是为什么你看到40000，而不是50000

在员工getSalary方法中，将值中的一个作为double得到浮点除法，这样的结果就是你想要的。

this.salary = this.wageRate * ((double) this.workedHours/workingHours); 

你的代码的输出：

$ java OOP 
Carl Cracker's salary this month is 75000.00 
Harry Hacker's salary this month is 50000.00 
Tony Tester's salary this month is 40000.00 

更改代码的输出：

$ java OOP 
Carl Cracker's salary this month is 75000.00 
Harry Hacker's salary this month is 51562.50 
Tony Tester's salary this month is 50000.00