標記接口

class Book implements Cloneable{  private  String name;  public Book(String name){   this.name=name;   }  @Override  public Book clone(){   Book book=null;   try {    book=(Book)super.clone();   }catch(CloneNotSupportedException e){    e.printStackTrace();   }  } } public class Clone {  public static  void main(String[] args){   Book book1=new Book("Java");   Book book2=book1.clone();  } }