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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
this.preferred = preferred;
    }
    public Integer getWeight() {
        return weight;
    }
    public void setWeight(Integer weight) {
        this.weight = weight;
    }
    @Parameter(key = REGISTER_MODE_KEY)
    public String getRegisterMode() {
        return registerMode;
    }
    public void setRegisterMode(String registerMode) {
        this.registerMode = registerMode;
    }
    @Parameter(key = ENABLE_EMPTY_PROTECTION_KEY)
    public Boolean getEnableEmptyProtection() {
        return enableEmptyProtection;
    }
    public void setEnableEmptyProtection(Boolean enableEmptyProtection) {
        this.enableEmptyProtection = enableEmptyProtection;
    }
    @Override
    @Parameter(excluded = true, attribute = false)
    public boolean isValid() {
        
        return !StringUtils.isEmpty(address) || !StringUtils.isEmpty(protocol);
    }
}