[Solved] If a class implements serializable interface then is its child class also serialize or not?

Question

The Serializable interface does nothing by itself, it is merely, as you remarked, a marker interface to show Java that this particular class is serializable. That means that if you denote a class with this interface, all child classes will be treated as serializable by themselves (just like normal inheritance), but the task of a successfully serialization must be ensured by you, as you control which fields your classes contain – and every field whose type does not implement Serializable will break the contract.

Accepted Answer

The Serializable interface does nothing by itself, it is merely, as you remarked, a marker interface to show Java that this particular class is serializable. That means that if you denote a class with this interface, all child classes will be treated as serializable by themselves (just like normal inheritance), but the task of a successfully serialization must be ensured by you, as you control which fields your classes contain – and every field whose type does not implement Serializable will break the contract.