@Override
    public void unregisterClient(Client client, IAsyncResultHandler<Void> handler) {
        try {
            unregisterClientInternal(client, false);
            handler.handle(AsyncResultImpl.create((Void) null));
        } catch (RegistrationException e) {
            handler.handle(AsyncResultImpl.create(e, Void.class));
        }
    }
@see io.apiman.gateway.engine.IRegistry#unregisterClient(io.apiman.gateway.engine.beans.Client, io.apiman.gateway.engine.async.IAsyncResultHandler)
gateway/engine/core/src/main/java/io/apiman/gateway/engine/impl/InMemoryRegistry.java