对每个创建的对象调用一个方法

Question

我一直在想，有没有办法为一个特定类的每个对象调用一个方法？

假设我有个课：

public class Employee {
private double salary;
private boolean hired;

public double getSalary() {return salary;}
public double setSalary(double x) {salary=x;}

public boolean getHired() {return hired;}
public boolean setHired(boolean check) {hired=check;}

}

然后，我声明了另一个扩展Employee的类，例如Boss (因为Boss也是雇员，对吧)

因此，他继承了雇员的“获得”和“设定”，也有可能解雇雇员：

public class Boss extends Employee {

public void fireTheGuy(Employee unluckyYou) {
    boolean temp;
    temp=false;
    unluckyYou.setHired(temp);
    unluckyYou.setSalary(0.0);
}

这主要允许：

public static void main(String args[])
{
     Employee worker1 = new Employee();
     Employee worker2 = new Employee();
     Boss slacker = new Boss();
     slacker.fireTheGuy(worker1);
     slacker.fireTheGuy(worker2);
}

但如果我有大约100名员工而老板却想把他们全部解雇呢？如何调用此方法(这是否可以通过某种循环实现？)

Answer 1

您可以让所有员工在公共的static List中注册自己。然后，当老板被告知解雇每个人时，他只是按单子走。

static List<Employee> allEmployees = new ArrayList<>();

public class Employee {
    private double salary;
    private boolean hired;

    public Employee() {
        // All employees must register themselves in the allEmployees list.
        allEmployees.add(this);
    }

    public double getSalary() {return salary;}
    public double setSalary(double x) {salary=x;}

    public boolean getHired() {return hired;}
    public boolean setHired(boolean check) {hired=check;}

}

public class Boss extends Employee {

    public void fireTheGuy(Employee unluckyYou) {
        unluckyYou.setHired(false);
        unluckyYou.setSalary(0.0);
    }

    public void fireThese(Iterable<Employee> fireThem) {
        for ( Employee e : fireThem ) {
            fireTheGuy(e);
        }
    }

    public void fireEveryone() {
        fireThese(allEmployees);
    }
}

Answer 2

这是你可以做的代码的一个例子。

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

employees.add(worker1);
employees.add(worker2);

for(Employee worker:employees){
    slacker.fireTheGuy(worker);
}

但是，就像注释中提到的那样，您应该尝试理解这个示例背后的所有概念。