public void ensureIndexIsVisible (int index)

Scrolls the list within an enclosing viewport to make the specified cell completely visible. This calls scrollRectToVisible with the bounds of the specified cell. For this method to work, the JList must be within a JViewport.

If the given index is outside the list's range of cells, this method results in nothing.

index    the index of the cell to make visible

See also:
JComponent.scrollRectToVisible, getVisibleRect