You can use HTML in a JList, and I'm not aware of why that would be a bad practice - unless when the user selects a row, you are now checking whether the selected item is <b>thing</b>
rather than just thing
. But if you're doing something better than string comparisons on the selected list items, this shouldn't be a problem.
If you're using DefaultListCellRenderer
, this is the only way I know that you can make some part of an item bold.