Index: src/main/java/common/javax/swing/plaf/basic/BasicListUI.java =================================================================== --- src/main/java/common/javax/swing/plaf/basic/BasicListUI.java (revision 490282) +++ src/main/java/common/javax/swing/plaf/basic/BasicListUI.java (working copy) @@ -432,6 +432,10 @@ } public int locationToIndex(final JList list, final Point location) { + if (location == null) { + throw new NullPointerException(); + } + layouter.setList(list); maybeUpdateLayoutState();