How to serialize a non-serializable in Java?
You can't serialise a class that doesn't implement Serializable
, but you can wrap it in a class that does. To do this, you should implement readObject
and writeObject
on your wrapper class so you can serialise its objects in a custom way.
- First, make your non-serialisable field
transient
. - In
writeObject
, first calldefaultWriteObject
on the stream to store all the non-transient fields, then call other methods to serialise the individual properties of your non-serialisable object. - In
readObject
, first calldefaultReadObject
on the stream to read back all the non-transient fields, then call other methods (corresponding to the ones you added towriteObject
) to deserialise your non-serialisable object.
I hope this makes sense. :-)
Wrap the non-serializable class in a class of your own that implements Serializable
. In your class's writeObject
method, do whatever's necessary to serialize sufficient information on the non-serializable object so that your class's readObject
method can reconstruct it.
Alternatively, contact the developer of the non-serializable class and tell him to fix it. :-)
You can use Kryo. It works on non serialized classes but classes needs registered aforehand.