How Do Java Serializable Objects Work?

Java serializable objects are common in Java programming. But what are they and how do they work? This is a question that you will meet in your interview as you pursue a Java programming related job. Therefore, we provide you with the best answers for the question in this article.

What Are Java Serializable Objects?

Serializing an object refers to converting it (plus its references) to a byte stream state so that the byte stream can be transformed back into a duplicate of the object. Only an object whose class or one of its superclasses executes either the ‘java.io.Serializable’ interface or a ‘java.io.Externalizable’ subinterface can achieve this. The serialized object can be transformed back into a copy of the object through the deserialization process.

How Do Java Serializable Objects Work?

In Java programming language, a standard mechanism carries out serialization on the Java Serialization API. Usually, Java sees everything as objects. When there is a call for communication between two objects, there has to be a way of data exchange. The first option is to set your protocol to replicate the object.

However, that would make communicating with third party components rather difficult. Therefore, serializable Java acts as a generic and efficient protocol to help solve that problem. The Java serializable algorithm handles the entire job during the communication. It operates in the following ways:

  • It writes the metadata of the class affiliated to an instance.
  • Writes the description of the superclass recursively until it finds the java.lang.object.
  • Upon terminating the process of writing metadata, it commences with the real data corresponding to the instance starting from the uppermost class.
  • Writes the data affiliated with the instance in a recursive manner. It begins with the least superclass and ends with the class that is derived the most.

What are the Uses of Serialization?

  • Persists the data for future reference.
  • Sends data to remote clients via server Java technologies such as RMI or socket programming.
  • ‘Flattens’ a Java component into a stream of bytes in the memory.
  • Transfers data between applets and servlets.
  • Activates or makes passive java beans enterprise.
  • Transmits objects between clients or servers in a cluster.

Recommended reads: Since you’re here, you might also be interested in our collection of Java interview questions, how to reverse a linked list in Java, or the difference between method overloading and method overriding!

Conclusion

These are some of the answers you can give in case you encounter the interview question on how Java serializable objects work. Make sure to give the interviewer the impression that you actually have experience with the serialization process. That way you will ace your interview easily. Also, share your opinion with us on how you feel about our answers to this interview question!