序列化中子父类构造函数问题

一 介绍
1、如果父类实现了序列化接口,子类就不需要实现序列化接口。
2、创建对象的时候,递归调用了父类的构造函数。
3、 对子类对象进行反序列化操作时, 如果其父类没有实现序列化接口, 那么其父类的构造函数会被调用,否则不会被调用。
 
二 实例
package com.imooc.io;
 
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
 
public class ObjectSeriaDemo2 {
     public static void main(String[] args) throws Exception{
         ObjectOutputStream oos = new ObjectOutputStream(
                  new FileOutputStream( "demo/obj1.dat" ));
         Foo2 foo1 = new Foo2();    //创建对象的时候,递归调用了父类的构造函数
         oos.writeObject(foo1);
         oos.flush();
         oos.close();
         
          //反序列化是否递归调用父类的构造函数,不能证明
         ObjectInputStream ois = new ObjectInputStream(
                  new FileInputStream( "demo/obj1.dat" ));
         Foo2 foo2 = (Foo2)ois.readObject();
         System. out .println(foo2);
         ois.close();
         
         
         ObjectOutputStream oos1 = new ObjectOutputStream(
                  new FileOutputStream( "demo/obj1.dat" ));
         Bar2 bar1 = new Bar2();
         oos1.writeObject(bar1);
         oos1.flush();
         oos1.close();
         
         ObjectInputStream ois1 = new ObjectInputStream(
                  new FileInputStream( "demo/obj1.dat" ));
         Bar2 bar2 = (Bar2)ois1.readObject();
         System. out .println(bar2);
         ois1.close();
         
         
          /*
          * 对子类对象进行反序列化操作时,
          * 如果其父类没有实现序列化接口
          * 那么其父类的构造函数会被调用
          */
    }
}
/*
 *   一个类实现了序列化接口,那么其子类都可以进行序列化
 */
class Foo implements Serializable{ 
     public Foo(){
         System. out .println( "foo..." );
    }
}
class Foo1 extends Foo{
     public Foo1(){
         System. out .println( "foo1..." );
    }
}
class Foo2 extends Foo1{
     public Foo2(){
         System. out .println( "foo2..." );
    }
}
class Bar{
     public Bar(){
         System. out .println( "bar" );
    }
}
class Bar1 extends Bar{
     public Bar1(){
         System. out .println( "bar1.." );
    }
}
class Bar2 extends Bar1 implements Serializable{
     public Bar2(){
         System. out .println( "bar2..." );
    }
}
 
三 运行结果
foo...
foo1...
foo2...
com.imooc.io.Foo2@913fe2
bar
bar1..
bar2...
bar
bar1..
com.imooc.io.Bar2@eb7859

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转载自cakin24.iteye.com/blog/2392867