Question

After going through the article at http://geekexplains.blogspot.com/2008/06/diff-between-externalizable-and.html, i got to know Externalizable is better than Serializalable as it provides better control on code and also faster .So Externalizable should be preffered instead of Serializable provided class definition is not changed.But when i see in any project i find using Serializable interface only. can it be ignorance or Serializalable provides some other advantage which i am missing?

Answer 1

The advantage of Serializable is it’s incredibly easy to implement, and resilient to change (in most cases all you have to do is update the serialversionUID). Externalizable requires the programmer to actually do work, and do more work every time the contents of the class change. As the article you link to points out implementing Externalizable is also error-prone. So from the point of view of utilizing limited programmer time, often Serializable is a better choice.

The good thing about how Serializable and Externalizable are designed is that you can defer the decision to implement Externalizable until it becomes evident there’s a performance problem, and you can selectively implement it only for those classes where there’s a problem.