When a JList has a selection mode set to ListSelectionModel.SINGLE_SELECTION, the first and last index values of ListSelectionEvents show a range of selection values instead of the single selection index. The selection model returns the correct value for getMinSelectionIndex() and getMaxSelectionIndex(), however. If I understand the documentation, listSelectionEvent.getFirstIndex() should equal listSelectionModel.getMinSelectionIndex() and listSelectionEvent.getLastIndex() should equal listSelectionModel.getMaxSelectionIndex(), regardless of selection mode.