serialization question - pls help me!

[adam Lui]

I dont understand the effect of serialization. What can it actually contribute to the following objects and code?

i just cant see it!

i tried to test the effect by altering the code but dont know where to start...coz i am not quite sure (still) what serialization is ALL about!

K&B added in order to alter the standard deserialization process you would override the readObject() method in SpecialSerial. Why???

and most importantly, if serialization is about saving objects (instance variables), line 9's ++s.z is outside os.close(),
how come on line 14, the value changed?

====here is the code======
import java.io.*;
public class TestSer {
public static void main(String[] args) {
SpecialSerial s = new SpecialSerial();
try {
ObjectOutputStream os = new ObjectOutputStream(new FileOutputStream("myFile"));
os.writeObject(s);
os.close();
System.out.println(++s.z + " "); //line 9

ObjectInputStream is = new ObjectInputStream(new FileInputStream("myFile"));
SpecialSerial s2 = (SpecialSerial)is.readObject();
is.close();
System.out.println(s2.y + " " + s2.z); //line 14
} catch (Exception x)
{System.out.println("exc"); }
}
}

class SpecialSerial implements Serializable {
transient int y = 7;
static int z = 9;
void readObject(){ };
}
[ September 17, 2007: Message edited by: adam lui ]

[Ajay Chandravadiya]

Adam,
Please dont mind , but you need to do your homework here.

1. its "private void readObject(Objectlnputstream os) {} " that is to be overridden and NOT readObject(); // No Params?!
2. Serialization is NOT for Transients. All transients will be given Default value of its datatype when object is deserialized.
3. Serialization is NOT for Statics. All Static variables, even though when referred thru Object Reference, fetches its value from Class (and not Object).

Please let me know if I can still help.

[Roland Schneider]

1. No readObject(...) Method can be overriden, the method must be implemented in any class which needs special treatment in the deserialization process.

2. Static members should be accessed in a way like SpecialSerial.z and then it's very easy to see why static member vars are not serialized.

[ September 19, 2007: Message edited by: Roland Schenner ]
[ September 19, 2007: Message edited by: Roland Schenner ]

[dolly shah]

Please refer below link. You will clear.
here

[Burkhard Hassel]

Howdy "Ajay C" !

Thanks for your contribution to this forum.

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