将收件人头像发布到全局地址列表（GAL）

public class Animal {
public void talkTo(Animal a){
System.out.println("animal");
}
}

public class Cat extends Animal {
public void talkTo(Cat c){
System.out.println("Cat");
super.talkTo(c);
}
public static void main(String [] args){
Cat c = new Cat();
Animal a = new Animal();
c.talkTo(a);
c.talkTo(c);
}
}