JTable and TableModel:

"All" there is to do is to call JScrollPane.setRowHeaderView().

(Install JScrollPane bug fix for proper synchronization of row/column header and main component.)

You may use either a separate JTable or a JList as a row header.

JList has the disadvantage that it uses a different model and a different strategy for row height. Both make proper synchronization harder.

I think in almost all cases a JTable is the better choice.