public void testAddMemberOnNonExistentGroupThrows() throws Exception {
        final JID needle = new JID("jane@" + Fixtures.XMPP_DOMAIN);
        final DefaultGroupProvider provider = new DefaultGroupProvider();
        provider.createGroup("Test Group A");

        assertThrows(GroupNotFoundException.class, () -> provider.addMember("Test Group B", needle, false));
    }
Verifies that {@link DefaultGroupProvider#addMember(String, JID, boolean)} throws a
{@link GroupNotFoundException} when attempting to add a member to a group by a name that does not exist
xmppserver/src/test/java/org/jivesoftware/openfire/group/DefaultGroupProviderTest.java