Serialization doubt

[Seetharaman Venkatasamy]

i Serialize the class A object in class A and store in test.ser file . then i DeSerialize the object from class B .here i notice serializa and Deserialize objects are same[no new object created] . but if i deserialize[serialize+deserialize] in same class A , then i am getting new Object

[Vijitha Kumara]

 

seetharaman venkatasamy wrote:... then i DeSerialize the object from class B .here i notice serializa and Deserialize objects are same[no new object created] . ...

How did you test it ? Are you deserializing in the same JVM? Then how ?

[Maneesh Godbole]

http://faq.javaranch.com/java/TellTheDetails

[Seetharaman Venkatasamy]

 

Maneesh Godbole wrote:http://faq.javaranch.com/java/TellTheDetails

public class Rob implements Serializable{
private static final Rob rob = new Rob();
public static void main(String[] args)
{
try
{
OutputStream out = new FileOutputStream("c:\\test.ser");
ObjectOutputStream objOut = new ObjectOutputStream(out);
objOut.writeObject(rob);
System.out.println("Serialized Successfully!"+rob);
//Deserialize
InputStream out1 = new FileInputStream("c:\\test.ser");
ObjectInputStream objIn = new ObjectInputStream(out1);
Rob rob1 = (Rob)objIn.readObject();
System.out.println("DeSerialized Successfully!"+rob1);
}
catch(Exception ex)
{
ex.printStackTrace();
}
}
}

i tested in same jvm only.the asware is

Serialized Successfully!com.Rob@9304b1
DeSerialized Successfully!com.Rob@190d11

if i remove the Deserialization part from Rob and put the in separate class[Test]

public class Test implements Serializable{
/**
*
*/
private static final long serialVersionUID = 2640934692335200272L;
public static void main(String[] args)
{
try
{
//Rob rob = new Rob();
InputStream out = new FileInputStream("c:\\test.ser");
ObjectInputStream objIn = new ObjectInputStream(out);
Rob rob1 = (Rob)objIn.readObject();
System.out.println("DeSerialized Successfully!"+rob1);
}
catch(Exception ex)
{
ex.printStackTrace();
}
}
}

if you run both class separatly

then output

//Both are same object
Serialized Successfully!com.Rob@9304b1
DeSerialized Successfully!com.Rob@9304b1

i am not sure whether i confuse. but please some one explain

[Vijitha Kumara]

 

seetharaman venkatasamy wrote:if i remove the Deserialization part from Rob and put the in separate class[Test]
if you run both class separatly then output

//Both are same object
Serialized Successfully!com.Rob@9304b1
DeSerialized Successfully!com.Rob@9304b1

You are running them separately so it's obvious they are not the same but heppens to have the same hashcode values generated by the JVM.

[Seetharaman Venkatasamy]

 

Vijitha Kumara wrote:

seetharaman venkatasamy wrote:if i remove the Deserialization part from Rob and put the in separate class[Test]
if you run both class separatly then output

//Both are same object
Serialized Successfully!com.Rob@9304b1
DeSerialized Successfully!com.Rob@9304b1

You are running them separately so it's obvious they are not the same but heppens to have the same hashcode values generated by the JVM.

well, then what about my first scenario result ?

[Vijitha Kumara]

 

seetharaman venkatasamy wrote:well, then what about my first scenario result ?

Serialized object has nothing to do with the deserialized one, those are two different objects.

[Seetharaman Venkatasamy]

Thanks Vijitha . somehow i got

[Vijitha Kumara]

 

java.io.ObjectInputStream wrote:New objects are always allocated when deserializing, which prevents existing objects from being overwritten.

Just to confirm

[Seetharaman Venkatasamy]

 

Vijitha Kumara wrote:

java.io.ObjectInputStream wrote:New objects are always allocated when deserializing, which prevents existing objects from being overwritten.

Just to confirm