Java - Deserialization InvalidClassException (No valid constructor)

Question

I\'m trying to serialize an object and then deserialize it after sending its data to a client program.

Here\'s an example of how the object\'s inheritance works. The obj

Answer 1

Good explanation is done in answers for following question Deserializing an ArrayList. no valid constructor

Long story short - you need no-arg constructor for first nonserializable super class of your class, NPC in your case.

If you don't have an access to NPC and it doesn't contain no-arg constructor - then you can add one more 'fake' class to hierarchy which will choose the correct one. E.g.

class SomeClass extends NPC {
// will be called during deserialization
public SomeClass(){
// call custom constructor of NPC
super(null);
}
}

class Person extends SomeClass implements Serializable {
// ..
}