java---- 类之间的继承

text.java

public class text {public static void main(String args[]) {fatty f=new fatty();food fo=new food();food po=new potpie();f.digest(fo);f.digest(po);}}

potpie.java

public class potpie extends food{void eat(){System.out.println("this potpie is great");}}

tune.java

public class tune {void eat(){System.out.println("this tune is great");}}

food.java

public class food {void eat(){System.out.println("this food is great");}}

fatty.java

public class fatty {public void digest(food x){x.eat();}}