It is an old post, but I came across this recently
Selecting a specific interval
As @aleroot already mentioned, by using
table.setRowSelectionInterval(index0, index1);
You can specify an interval, which should be selected.
Adding an interval to the existing selection
You can also keep the current selection, and simply add additional rows by using this here
table.getSelectionModel().addSelectionInterval(index0, index1);
This line of code additionally selects the specified interval. It doesn't matter if that interval already is selected, of parts of it are selected.