### Question:
FlowDirectionHelper { public static Direction findDirection(long rawCookie) throws FlowCookieException { return findDirectionSafe(rawCookie) .orElseThrow(() -> new FlowCookieException(String.format( "unknown direction for %s", new Cookie(rawCookie)))); } private  FlowDirectionHelper(); static Direction findDirection(long rawCookie); static Optional<Direction> findDirectionSafe(long rawCookie);  }### Answer:
@Test public void findDirectionTest() throws Exception { assertEquals(Direction.FORWARD, FlowDirectionHelper.findDirection(FORWARD_COOKIE)); assertEquals(Direction.REVERSE, FlowDirectionHelper.findDirection(REVERSE_COOKIE)); thrown.expect(FlowCookieException.class); FlowDirectionHelper.findDirection(BAD_COOKIE); }