Serializing and Deserializing android causes InvalidClassException android.os.MemoryFile IllegalAccessException

Question

I have used android.os.MemoryFile class to serialize and deserialize it's objects. What I have done is, I have created custom class name like MyMemoryFile and extends this with MemoryFile class and implement Serializable interface. I override MemoryFile class functions like ReadBytes/WriteBytes. Then I converted all objects into byte array and store in byte ArrayList. Then I converted all byte ArrayList items into String to store in Mysql database and vise versa . I have done this but when I deserialize objects it causes an exception

java.io.InvalidClassException: android.os.MemoryFile; IllegalAccessException

Unfortunately, the in.readObject() throws an InvalidClassException with the message above.

Does anyone know what is causing this and how to fix it?

Answer 1

InvalidClassException means there is a difference in the Class definition (in terms of members, a new member might have been added) after you stored objects of those class in database which lead into this problem when you retrieved them back and tried to deserialize . Define "serialVersionUID" in your serializable class and the problem will be gone.