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## Ask your question here
![1678891955524](https://user-images.githubusercontent.com/31841743/225348655-2b03b0b0-2da0-4e34-bfd0-be07e6e54d60.jpg)
![1678891971675](https://user-images.githubusercontent.com/31841743/225348708-57f4df91-77c5-4b32-9e4e-cde573002ad2.jpg)
![image](https://user-images.githubusercontent.com/31841743/225348805-4a38363d-25c3-4245-ab33-ea1772c3f115.png)
可以看到按照图片顺序，properties中设置default属性，在我从configManager中打印的2个注册中心default值都为null,dubbo版本是3.0.12
* @since 2.7.0
     */
    private Boolean simplified;
    /**
     * After simplify the registry, should add some parameter individually. just for provider.
     * <p>
     * such as: extra-keys = A,b,c,d
     *
     * @since 2.7.0
     */
    private String extraKeys;
    /**
     * the address work as config center or not
     */
    private Boolean useAsConfigCenter;
    /**
     * the address work as remote metadata center or not
     */
    private Boolean useAsMetadataCenter;
    /**
     * list of rpc protocols accepted by this registry, for example, "dubbo,rest"
     */
    private String accepts;
    /**
     * Always use this registry first if set to true, useful when subscribe to multiple registries
     */
    private Boolean preferred;
    /**
     * Affects traffic distribution among registries, useful when subscribe to multiple registries
     * Take effect only when no preferred registry is specified.