Question

所以，我有一个OOP课程，我的任务是创建一个抽象的员工类，而不是为它制作更多的基类。这部分很简单，之后我不得不创建一个'Employee'类型的对象数组，并使用整个多态性来相应地启动所有基类。

这是我在主编中写的代码：

Scanner input = new Scanner (System.in);

    int Size;
    System.out.println("Enter Array Size");
    Size = input.nextInt();

    Employee [] Array = new Employee [Size];

    int i;
    int A;

    System.out.println("Key: ");
    System.out.println("Press 1 for Salaried Employee.");
    System.out.println("Press 2 for Hourly Employee.");
    System.out.println("Press 3 for Commision Employee.");
    System.out.println("Press 4 for Base Plus Commision Employee.");


    String Name;
    String SSN;
    double wage;
    double hours;
    double salary;
    int Sales;
    double CRate;
    double BaseSalary;

    for (i = 0; i < Array.length; i++ ) {
        A = input.nextInt();
        if (A == 1) {

            do {
                System.out.println("Enter Name");
                input.nextLine();
                Name = input.nextLine();
            } while (Name == "");

            do {
                System.out.println("Enter Social Security Number");
                SSN = input.nextLine();
            } while (SSN == "");

            Array [i] = new Salaried_Employee(Name, SSN);

            System.out.println("Initial Earnings!" +Array[i].Earnings());


        }
        if (A == 2) {
            do {
                System.out.println("Enter Name");
                input.nextLine();
                Name = input.nextLine();
            } while (Name == "");

            do {
                System.out.println("Enter Social Security Number");
                SSN = input.nextLine();
            } while (SSN == "");

            System.out.println("Enter Wage!");
            wage = input.nextDouble();

            System.out.println("Enter hours!");
            hours = input.nextDouble();

            Array [i] = new Hourly_Employee (Name, SSN, wage, hours);
        }

        if (A == 3) {
            do {
                System.out.println("Enter Name");
                input.nextLine();
                Name = input.nextLine();
            } while (Name == "");

            do {
                System.out.println("Enter Social Security Number");
                SSN = input.nextLine();
            } while (SSN == "");

            System.out.println("Enter Sales!");
            Sales = input.nextInt();

            System.out.println("Enter Commision Rate!");
            CRate = input.nextDouble();

            Array [i] = new Comission_Employee (Name, SSN, Sales, CRate);
        }

        if (A == 4) {
            do {
                System.out.println("Enter Name");
                input.nextLine();
                Name = input.nextLine();
            } while (Name == "");

            do {
                System.out.println("Enter Social Security Number");
                SSN = input.nextLine();
            } while (SSN == "");

            System.out.println("Enter Sales!");
            Sales = input.nextInt();

            System.out.println("Enter Commision Rate!");
            CRate = input.nextDouble();

            System.out.println("Define the base salary");
            BaseSalary = input.nextDouble();

            Array [i] = new BassPlus_CommEmployee (Name, SSN, Sales, CRate, BaseSalary);
        }
    }

现在我必须通过Array List做同样的事情。我已经搜索了这个问题的生命，但我不知道如何创建一个Employee类型的ArrayList。

请帮助!!

Answer 1

List<Employee> employeeList = new ArrayList<Employee>();

编辑：

employeeList.add(new BassPlus_CommEmployee (Name, SSN, Sales, CRate, BaseSalary));
employeeList.add(new Hourly_Employee (Name, SSN, wage, hours));

等

我假设员工是Superclass。好吧，我认为这是因为您在代码中使用了这个确切的片段。

Answer 2

ArrayList是包含其他Object的{{1}}。因此，您必须调用方法来替换您使用Object进行的分配。

Array可以转置为array[i] = new Employee();，例如

然后，您需要找到如何arraylist.add(new Employee())转置值get

不要忘记不使用null Employee e = array[i]。

如何使用Array和ArrayList做同样的事情？

2 个答案: