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abstract class Animal //¶¨Òå³éÏóÀà
{
String str;
Animal(String s) //¶¨Òå³éÏóÀàµÄÒ»°ã·½·¨
{
str=s;
}
abstract void eat(); //¶¨Òå³éÏó·½·¨
}
class Horse extends Animal //¶¨Òå¼Ì³ÐAnimalµÄ×ÓÀà
{
String str;
Horse(String s)
{
super(s); //µ÷Óø¸ÀàµÄ¹¹Ôì·½·¨
}
void eat() //ÖØÐ´¸¸ÀàµÄ³éÏó·½·¨
{
System.out.println("Âí³Ô²ÝÁÏ£¡");
}
}
class Dog extends Animal
{
String str;
Dog(String s)
{
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public class User implements Serializable{
private static final long serialVersionUID = 1L;
private Integer id;
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