[COLLECTIONS-444] SetUniqueList may become inconsistent

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.2.1
• Fix Version/s: 3.2.2, 4.0-alpha1, 4.0
• Component/s: List
• Assignee: Unassigned
• Reporter: Thomas Vahrst
• Created: 25/Feb/13 20:08
• Updated: 09/Nov/15 00:36
• Resolved: 17/Apr/13 22:13

Description

I found this bug during my work on issue COLLECTIONS-310 :

When you 'set' an element to a position that contains this element, it is removed from the internal set. This leads to the situation that

• invocing get() returns the element
• invocing contains() returns false.

Extending the existing test method for set:

   public void testSet() {
        final SetUniqueList<E> lset = new SetUniqueList<E>(new ArrayList<E>(), new HashSet<E>());

        // Duplicate element
        final E obj1 = (E) new Integer(1);
        final E obj2 = (E) new Integer(2);
        final E obj3 = (E) new Integer(3);

        lset.add(obj1);
        lset.add(obj2);
        lset.set(0, obj1);
        assertEquals(2, lset.size());
        assertSame(obj1, lset.get(0));
        assertSame(obj2, lset.get(1));

        assertTrue(lset.contains(obj1));  // fails !
        assertTrue(lset.contains(obj2));

Issue Links

• is related to: COLLECTIONS-310 Modifications of a SetUniqueList.subList() invalidate the parent list