@Test
    public void shouldNotStoreErrorMessages() {
        // XEP-0160: "error" message types SHOULD NOT be stored offline,
        Message message = new Message();
        message.setType(Message.Type.error);
        assertFalse(OfflineMessageStore.shouldStoreMessage(message));
    }
This tests the business rules for storing messages as described in <a href="http://xmpp.org/extensions/xep-0160.html#types">3. Handling of Message Types</a>.

@author csh
xmppserver/src/test/java/org/jivesoftware/openfire/OfflineMessageStoreTest.java