Why are transient static variables allowed?

[Ruben Soto]

I was just wondering why we can declare a variable to be transient and static. Since static variables are never serialized, it seems that the use of transient is superfluous.

[Deepak Bala]

it seems that the use of transient is superfluous

Just like declaring an interface abstract

[Ruben Soto]

Deepak Bala wrote:

it seems that the use of transient is superfluous

Just like declaring an interface abstract

Thanks Deepak. I was wondering if there is any scenario which I might have overlooked which made the rationale for this something besides allowable superfluousness.

[Kavita Tipnis]

I don't think it is superfluous, consider the following situation. [Read the topic wrong!!!]
1) Serialize an Object
2) Do Some operations using the transient variable (increment or pass it to some method..)
3) Deserialize the Object
4) Try accessing the transient variable , it will be initialized to the default value.

But if you have marked the variable static, then it will not be initialized because the static does not belong to a particular instance.

I cranked some code to check this out.

  
public class Test {
    
    public static void main(String[] args){
        Dog d=new Dog();
        
        try{
         
            System.out.println("Before serialization...");
            System.out.println("i="+d.i+" x="+d.x);
         
            //serialize
            FileOutputStream fos=new FileOutputStream("C:\\test.txt");
            ObjectOutputStream os=new ObjectOutputStream(fos);
            os.writeObject(d);
       
            //Modify instance variable i and x
            d.i++;
            d.x++;
        
            //deserialize
            FileInputStream fis=new FileInputStream("C:\\test.txt");
            ObjectInputStream ois=new ObjectInputStream(fis);
        
            d=(Dog)ois.readObject();
            }catch(Exception ex){
            
            }
            System.out.println("After deserialization...");
            System.out.println("i="+d.i+" x="+d.x);
        }
    

}
class Dog implements Serializable{
    int i=5;
    transient static int x=10;
    Dog(){
        
    }
    
} 
 

[Kavita Tipnis]

Oops sorry , I read your question wrong the other way round!! but never mind the code can be a mock quiz question!
It is superfluous! [Ignore my earlier post's verbage !!]

[Ruben Soto]

No problem Kavita. You can start your own mock exam product with this example!