public BackgroundException map(final IOException failure, final Path directory) {
        return super.map("Connection failed", failure, directory);
    }
@Test
    public void testMapWrappedCause() {
        final DefaultIOExceptionMappingService s = new DefaultIOExceptionMappingService();
        final BackgroundException cause = new BackgroundException();
        assertSame(cause, s.map(new IOException(cause)));
    }