FULL PRODUCT VERSION :
java version "1.5.0_06"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_06-b05)
Java HotSpot(TM) 64-Bit Server VM (build 1.5.0_06-b05, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux ubuntu 2.6.12-10-amd64-generic #1 Fri Apr 28 13:18:42 UTC 2006 x86_64 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
The setSelectionMode() specification doesn't say what happens to the existing selections when changing from a less restrictive mode to a more restrictive mode (for example, from SINGLE_INTERVAL_SELECTION to SINGLE_SELECTION).

It appears that the current implementation doesn't modify the selections at all, which leaves the model in an inconsistent state. See the example below, where a model ends up in SINGLE_SELECTION mode with two items selected.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
See executable test case.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I would expect at most 1 item to remain selected. Or perhaps the change of mode should clear all current selections.
ACTUAL -
Item 1 is selected : true
Item 2 is selected : true
1.5.0_06


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import javax.swing.DefaultListSelectionModel;
import javax.swing.ListSelectionModel;

public class ListSelectionModelTest {

    public static void main(String[] args) {
        System.out.println("Running on: " + System.getProperty("java.version"));
        DefaultListSelectionModel m = new DefaultListSelectionModel();
        m.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);
        m.setSelectionInterval(1, 2);
        m.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        System.out.println("Item 1 is selected : " + m.isSelectedIndex(1));
        System.out.println("Item 2 is selected : " + m.isSelectedIndex(2));
    }
}

---------- END SOURCE ----------