@Test
public void testCreateContentId() throws Exception {

    String id = MessageIdUtils.createMessageId();
    String[] idParts = id.split("@");
    String contentId = MessageIdUtils.createContentId(id);
    assertNotNull(contentId);
    String[] contentIdParts = contentId.split("@");
    assertTrue(contentIdParts.length == 2);
    assertTrue(contentIdParts[0].contains(idParts[0]));
    assertEquals(idParts[0],
            contentIdParts[0].substring(0, contentIdParts[0].lastIndexOf("-")));
    assertTrue(contentIdParts[0].length()>0);
    assertEquals(contentIdParts[1], hostname);
}