多态性的使用

public class Department {

    public String name;
    private int number;
    public Department() {
        super();
    }
    public Department(String name, int number) {
        super();
        this.name = name;
        this.number = number;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getNumber() {
        return number;
    }
    public void setNumber(int number) {
        this.number = number;
    }
    public void business(){
        System.out.println("为集团引进IT设备");
    }
    public int aveSalary(int sum){
        System.out.println("部门平均薪水"+sum);
        return sum;
    }

public class SoftDep extends Department {
    private boolean programming;

    public SoftDep() {
        super();
    }

    public SoftDep(boolean programming) {
        super();
        this.programming = programming;
    }

    public boolean isProgramming() {
        return programming;
    }

    public void setProgramming(boolean programming) {
        this.programming = programming;
    }
    public void business(){
        System.out.println("为集团引进软件和系统");
    }
    public int aveSalary(int sum){
        System.out.println("薪水较高");
        return sum;
    }
    public void future(){
        System.out.println("前景较好");
    }

package lianxi2;

public class HardDep extends Department {
    private boolean communicate;

    public boolean isCommunicate() {
        return communicate;
    }

    public void setCommunicate(boolean communicate) {
        this.communicate = communicate;
    }

    public HardDep() {
        super();
    }

    public HardDep(boolean communicate) {
        super();
        this.communicate = communicate;
    }

    @Override
    public int aveSalary(int sum) {
        System.out.println("薪水较低");
        return sum;
    }

    @Override
    public void business() {
        System.out.println("负责引进硬件设施和网络");
    }
    public void future(){
        System.out.println("前景堪忧");
    }
}

package lianxi2;

public class TestDep {
    public static void main(String[] args) {
        TestDep t = new TestDep();
        Department d = new Department("信息中心",001);
        //d.name;                         --------------只是一个属性不能作为语句，调用一个方法可以
        System.out.println(d.name);      
        System.out.println(d.getName());
        System.out.println(d.getNumber());
        d.business();
        System.out.println(d.aveSalary(4000));
        
        Department d1 = new SoftDep(true);     //向上转型，只能调用子类中重写父类的方法
        if(d1 instanceof SoftDep){           
        //    System.out.println(d1.isProgramming()); ---------------属性没有多态性
        System.out.println(d1.aveSalary(5000));
        d1.business();
        SoftDep so = (SoftDep)d1;            //向下转型，可以调用所有子类中的方法
        System.out.println("$"+so.aveSalary(5000));
        so.future();
        System.out.println(so.isProgramming()); 
        t.func(new SoftDep());
        }
        System.out.println("\n\n");
        t.func(new HardDep());
    }
    public void func(Department d3){
        d3.business();
        System.out.println(d3.aveSalary(6000));
        if(d3 instanceof HardDep){
            HardDep hd = (HardDep)d3;
            hd.future();
        }
        if(d3 instanceof SoftDep){
            SoftDep so = (SoftDep)d3;
            so.future();
        }
    }
}