String extractStem(String className) {
        if (className == null)
            return null;

        int lastDotIndex = className.lastIndexOf(CoreConstants.DOT);
        if (lastDotIndex == -1)
            return null;
        if ((lastDotIndex + 1) == className.length())
            return null;
        return className.substring(lastDotIndex + 1);
    }
@Test
    public void testStemExtraction() {
        assertNull(imh.extractStem(null));
        assertNull(imh.extractStem(""));
        assertNull(imh.extractStem("bla."));
        assertEquals("Foo", imh.extractStem("bla.Foo"));
        assertEquals("Foo", imh.extractStem("com.titi.bla.Foo"));

    }