assertFalse(StringUtil.isNotEmpty(""));
        assertTrue(StringUtil.isNotEmpty(" "));
    }

    /**
     *
     */
    @Test
    public void testDefaultString() {
        assertThat(StringUtil.defaultString(null), is(""));
        assertThat(StringUtil.defaultString(""), is(""));
        assertThat(StringUtil.defaultString("aaa"), is("aaa"));
    }

    /**