我们使用方法分组来用dubbo，每个分组有自己权限，但是dubbo:registry标签 username & password 不生效，
让我不得不使用
```
    <dubbo:registry
            address="zookeeper://username:pwd@ip:port"
            group="xxx"/>
```
这种写法失效
```
    <dubbo:registry
            address="zookeeper://ip:port"
            username="username"
            password="pwd"/>
```

public Integer getConnections() {
        return connections;
    }
    public void setConnections(Integer connections) {
        this.connections = connections;
    }
    @Parameter(key = REFERENCE_FILTER_KEY, append = true)
    public String getFilter() {
        return filter;
    }
    public void setFilter(String filter) {
        checkMultiExtension(Filter.class, FILE_KEY, filter);
        this.filter = filter;
    }
    @Parameter(key = INVOKER_LISTENER_KEY, append = true)
    public String getListener() {
        return listener;
    }
    public void setListener(String listener) {
        checkMultiExtension(InvokerListener.class, LISTENER_KEY, listener);
        this.listener = listener;
    }
    public String getLayer() {
        return layer;
    }
    public void setLayer(String layer) {
        checkNameHasSymbol(LAYER_KEY, layer);
        this.layer = layer;
    }
    public ApplicationConfig getApplication() {