None of the answers to two previous questions (here and here) resolve my problem.
I have a multi-column jtable for which I want to display string-content of some columns
If I got you right, I think you need a MultilineCellRenderer . There are already plenty of examples around. Normally they are based on a JTextArea to get the line wrap functionality.
I haven't used it myself yet, but here is an example, which looks kinda good at first view:
MultilineCellRenderer