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public class A {
public A() {
System.out.println("A");
}
}
public class B extends A implements Serializable {
public B() {
System.out.println("B");
}
}
public class Test {
public static void main(String... args) throws Exception {
B b = new B();
ObjectOutputStream save = new ObjectOutputStream(new FileOutputStream("datafile"));
save.writeObject(b);
save.flush();
ObjectInputStream restore = new ObjectInputStream(new FileInputStream("datafile"));
B z = (B) restore.readObject();
}
}

What is the output?

A.	A B A	B.	A B A B
C.	B B	D.	B

Answer and Explanation

Answer:A B A

Explanation:
On the time of deserialization , the Serializable object not create new object. So
constructor of class B does not called.
A is not Serializable object so constructor is called.

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