What happens if I don't implement Serializable when using Hashmap

Question

What would happen if I don't include "implements Serializable?"

public class Student implements Serializable {
    private String studentNumber;
    private String firstName;
    private String lastName;
    private ArrayList<Exam> exams;
}

Answer 1

Then Student will behave like a normal class i.e You will not able store the state of the Student object anywhere

Go through this : https://docs.oracle.com/javase/tutorial/jndi/objects/serial.html

Answer 2

The Student would not be Serializable, and it will act like a normal class.

Serialization is the conversion of an object to a series of bytes, so that the object can be easily saved to persistent storage or streamed across a communication link. The byte stream can then be deserialized - converted into a replica of the original object.

When you want to serialize an object, that respective class should implement the marker interface serializable. It just informs the compiler that this java class can be serialized.

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