【菜鸟求助】java接口问题

Java code:

package MainCon;

public interface Animal {
void voice();
}

class Dog implements Animal {
public void voice() {
System.out.println("W W!");
}
}
class cat implements Animal{
public void voice(){
System.out.println("M M!");
}
}
class pig implements Animal{
public void voice(){
System.out.println("GU LI");
}
}
class Store {
public static Animal get(String choice){
if(choice.equalsIgnoreCase("dog")){
return new Dog();
}else if(choice.equalsIgnoreCase("pig")){
return new Dog();
}else{
return new cat();
}
}
}
public class AnimalTest{
public static void main(String[]args){
Animal a1 = Store.get("dog");

a1.voice();

Animal a2 = Store.get("pig");

a2.voice();
}
}


AnimalTest类报错、
The public type AnimalTest must be defined in its own file

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我是个新学的菜鸟，撒都不懂，希望高手指点下。万分感谢！

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public interface Ani