Came across an issues that might be useful if FindBugs could detect.
1; public Boolean getter() {
2; return null;
3; }
4;
5; public void test() {
6; System.out.println( !getter() );
7; }
FindBugs already displays a warning for line 2, regarding potential null.
But line 6 regarding autoboxing a Boolean to boolean throws a NullPointerException, so might be useful to class as error for others.
==> https://github.com/spotbugs/spotbugs/issues/586