bzu-java(三)

abstract class Student{
   String name;
   int fee;
   Student(String name){
	   this.name=name;
   }   
   abstract void setFee(int fee);
   abstract int getFee();
}
 interface Salary{
	int getSalary();
}
 class Graduate extends Student implements Salary{
	int salary;
	Graduate(String name){
		super(name);
	}
	void setFee(int fee){
		this.fee=fee;
	}
	int getFee(){
		return fee;
	}
	public int getSalary(){
		this.salary+=1500;
		return salary;
	}
	boolean isLoan(){
		if(salary-fee>0)
			return false;
		else return true;
	}
	
}
class Teacher implements Salary{
	String name;
	int salary;
	Teacher(String name){
		this.name=name;
		
	}
	 public int getSalary(){
		this.salary+=3000;
		return salary;
	}
	
	
}
class University{
	void payOff(Salary s){
		s.getSalary();
	}
}
public class Test{
	public static void main(String args[]){
		Graduate g=new Graduate("小梁");
		g.setFee(1000);
		University u =new University();
		u.payOff(g);
		System.out.println("是否需要贷款 "+g.isLoan());
		Teacher t=new Teacher("大王");
		u.payOff(t);
	}
}

课堂练习1：教材160页4.编程题

interface Animal{
void cry();
String getAnimalName();
}
class Simulator{
	void playSound(Animal animal){
		animal.cry();
	}
	void getAnimalName(Animal animal){
		System.out.println(animal.getAnimalName());
	}
}
class  Cat implements Animal{
	String name="猫";
	public void cry(){
		System.out.println("猫");
	}
  public String getAnimalName(){
	return this.name;
}
}
class  Dog implements Animal{
	String name="狗";
	public void cry(){
		System.out.println("狗");
	}
    public String getAnimalName(){
	return this.name;}
}
public class Application{
	public static void main(String args[]){
		Simulator simulator=new Simulator();
		simulator.playSound(new Dog());
		simulator.playSound(new Cat());
	}
}