This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
If I understand your question well, you wrote an implementation of AbstractTableModel. And you are wondering whether you should consider this class a default or a custom model. If that's the question, then the answer is custom. As you created it, this cannot be a default model anymore. Hope this is it Stephane