扫描仪问题

Question

我正在编写一个初始化每个员工的值的程序，然后最终将其显示出来。 在第4个循环后，我仍然遇到扫描仪问题，但我关闭了java.lang.IllegalStateException扫描仪错误，任何建议都会有所帮助。

for(int x = 0; x < 5; x++)
{
    System.out.println("For an employee who get salary enter #1.");
    System.out.println("For an employee who's hourly enter #2.");
    System.out.println("For an employee who's paid comission enter #3");
    System.out.println("For an employee who's base & comission enter #4 or 0 to quit.");
    Employees[x] = keyboard.nextInt();
    switch (Employees[x])
    {
        case 1:
            System.out.println("Please enter your first name.");
            FName[x] = keyboard.next();
            System.out.println("Please enter your last name.");
            LName[x] = keyboard.next();
            System.out.println("Please enter your social security in format 111-11-1111");
            SS[x] = keyboard.next();
            System.out.println("Please enter your salary amount $.");
            Check[x] = keyboard.nextDouble();
            SalariedEmployee salariedEmployee = 
                 new SalariedEmployee( FName[x], LName[x], SS[x], Check[x] );
            employees[x] = salariedEmployee;
            break;
        case 2: 
            System.out.println("Please enter your first name.");
            FName[x] = keyboard.nextLine();
            System.out.println("Please enter your last name.");
            LName[x] = keyboard.nextLine();
            System.out.println("Please enter your social security in format 111-11-1111");
            SS[x] = keyboard.nextLine();System.out.println("Please enter your first name.");
            System.out.println("How many hours were worked?");
            Hours[x] = keyboard.nextInt();
            System.out.println("How much paid per hour?");
            Rate[x] = keyboard.nextDouble();
            HourlyEmployee hourlyEmployee = 
            new HourlyEmployee( FName[x], LName[x], SS[x], Hours[x], Rate[x] );
            employees[x] = hourlyEmployee;
            break;
        case 3: 
            System.out.println("Please enter your first name.");
            FName[x] = keyboard.nextLine();
            System.out.println("Please enter your last name.");
            LName[x] = keyboard.nextLine();
            System.out.println("Please enter your social security in format 111-11-1111");
            SS[x] = keyboard.nextLine();System.out.println("Please enter your first name.");
            System.out.println("What was your weekly sale?");
            CommissionSales[x] = keyboard.nextDouble();
            System.out.println("What is your percentage paid commission?");
            CommissionRate[x] = keyboard.nextDouble();
           HourlyEmployee hourlyEmployee = 
            new HourlyEmployee( FName[x], LName[x], SS[x], Hours[x], Rate[x] );
            employees[x] = hourlyEmployee;
            break;
        case 4:
            System.out.println("Please enter your first name.");
            FName[x] = keyboard.nextLine();
            System.out.println("Please enter your last name.");
            LName[x] = keyboard.nextLine();
            System.out.println("Please enter your social security in format 111-11-1111");
            SS[x] = keyboard.nextLine();
            System.out.println("What was your weekly sale?");
            CommissionSales[x] = keyboard.nextDouble();
            System.out.println("What is your percentage paid commission?");
            CommissionRate[x] = keyboard.nextDouble();
            System.out.println("Please enter your salary amount $.");
            Check[x] = keyboard.nextDouble();
            BasePlusCommissionEmployee basePlusCommissionEmployee = 
            new BasePlusCommissionEmployee( FName[x], LName[x], SS[x], CommissionSales[x], CommissionRate[x], Check[x]);
            employees[x] = basePlusCommissionEmployee;
            break;
    }       

Answer 1

如果在尝试使用Scanner方法时将其关闭，则您使用的所有Scanner方法都将引发IllegalStateException 。 在代码中的某处，您可能具有keyboard.close() 。 删除此行，或将其移到程序的末尾，您会很高兴。 从Java文档中：

关闭扫描仪后尝试执行搜索操作将导致IllegalStateException。