@Test
public void testGetCommonPrefix() {

	Assert.assertEquals(
		"/home/user1/tmp",
		StringUtil.getCommonPrefix(
			'/', "/home/user1/tmp/coverage/test",
			"/home/user1/tmp/covert/operator",
			"/home/user1/tmp/coven/members"));
	Assert.assertNull(
		StringUtil.getCommonPrefix('/', "/dir1/tmp", "/dir2/tmp"));
}