private IQHandler getHandler(String namespace) {
        IQHandler handler = namespace2Handlers.get(namespace);
        if (handler == null) {
            for (IQHandler handlerCandidate : iqHandlers) {
                IQHandlerInfo handlerInfo = handlerCandidate.getInfo();
                if (handlerInfo != null && namespace.equalsIgnoreCase(handlerInfo.getNamespace())) {
                    handler = handlerCandidate;
                    namespace2Handlers.put(namespace, handler);
                    break;
                }
            }
        }
        return handler;
    }
Determines if this instance has support (formally: has a IQ Handler) for the provided namespace.

@param namespace Identifier of functionality (cannot be null)
@return true if the functionality identified by the namespace is supported, otherwise false.
xmppserver/src/main/java/org/jivesoftware/openfire/IQRouter.java