A DESCRIPTION OF THE PROBLEM :
Method
public int getViewIndex(int index)
of class javafx.collections.transformation.SortedList<E>
behaves erroneously under certain conditions

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
See provided JUnit test method

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
SortedList.getViewIndex(int index) returns a negative value if index is outside of the list
ACTUAL -
SortedList.getViewIndex(int index) returns zero or throws AIOOBE for some index values outside of the list

--- Output of Test Case ---
Source list : [4, 1, 3, 2]
Sorted list : [1, 2, 3, 4]
sortedList.getViewIndex(0) = 3
sortedList.getViewIndex(1) = 0
sortedList.getViewIndex(2) = 2
sortedList.getViewIndex(3) = 1
sortedList.getViewIndex(4) = 0
sortedList.getViewIndex(5) = 0
sortedList.getViewIndex(6) = 0
Index 7 out of bounds for length 7
Index 8 out of bounds for length 7
Index 9 out of bounds for length 7


---------- BEGIN SOURCE ----------
@Test
public void test_SortedList_getViewIndex()
{
final var sourceList = FXCollections.observableArrayList(4, 1, 3, 2);
final var sortedList = new SortedList<>(sourceList, Integer::compare);
System.out.println("Source list : " + sourceList);
System.out.println("Sorted list : " + sortedList);
assertEquals(3, sortedList.getViewIndex(0));
assertEquals(0, sortedList.getViewIndex(1));
assertEquals(2, sortedList.getViewIndex(2));
assertEquals(1, sortedList.getViewIndex(3));
for (int i = 0; i < 10; i++)
{
try
{
System.out.println("sortedList.getViewIndex(" + i + ") = " + sortedList.getViewIndex(i));
}
catch (IndexOutOfBoundsException ex)
{
System.out.println(ex.getMessage());
}
}
// the following tests fail:
assertTrue(sortedList.getViewIndex(4) < 0);
assertTrue(sortedList.getViewIndex(5) < 0);
assertTrue(sortedList.getViewIndex(6) < 0);
assertTrue(sortedList.getViewIndex(7) < 0);
assertTrue(sortedList.getViewIndex(8) < 0);
assertTrue(sortedList.getViewIndex(9) < 0);
}

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

CUSTOMER SUBMITTED WORKAROUND :
Check index before calling the getViewIndex(int index) method

FREQUENCY : always