java深复制和浅复制

class Professor  implements Cloneable       
{    
     String name;    
     int age;    
     Professor(String name,int age)    
     {    
        this.name=name;    
        this.age=age;    
     } 
     public Object clone()    
     {    
         Object o=null;    
        try    
         {    
             o=super.clone();    
         }    
        catch(CloneNotSupportedException e)    
         {    
             System.out.println(e.toString());    
         }    
        return o;    
     }    
}    

class Student implements Cloneable    
{    
     String name;    
    int age;   
    Professor p;// 学生1和学生2的引用值都是一样的。    
    Student(String name,int age,Professor p)    
    {    
       this.name=name;    
       this.age=age;    
       this.p=p;    
    }    
    public Object clone()    
     {    
    	 Student o=null;    
         try    
          {    
              o=(Student)super.clone();    
          }    
         catch(CloneNotSupportedException e)    
          {    
              System.out.println(e.toString());    
          }    
          //o.p=(Professor)p.clone();  注释后为浅复制，s1和s2仍指向同一对象;去注释后为深复制
         return o;    
     }    

 public Object deepClone() throws IOException, ClassNotFoundException
    {
          //将对象写到流里
          ByteArrayOutputStream bo=new ByteArrayOutputStream();
          ObjectOutputStream oo=new ObjectOutputStream(bo);
          oo.writeObject(this);
          //从流里读出来
          ByteArrayInputStream bi=new ByteArrayInputStream(bo.toByteArray());
          ObjectInputStream oi=new ObjectInputStream(bi);
          return(oi.readObject());
    }

} public class Main {public static void main(String[] args) { Professor p=new Professor("wangwu",50); Student s1=new Student("zhangsan",18,p); Student s2=(Student)s1.clone(); s2.p.name="lisi"; s2.p.age=30; System.out.println("name="+s1.p.name+","+"age="+s1.p.age);//学生1的教授成为lisi,age为30。 }}