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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
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 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
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 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.dubbo.config;
import org.apache.dubbo.common.URL;
import org.apache.dubbo.common.utils.CollectionUtils;
import org.apache.dubbo.common.utils.StringUtils;
import org.apache.dubbo.config.support.Parameter;
import org.apache.dubbo.rpc.model.ApplicationModel;
import java.util.Map;
import static org.apache.dubbo.common.constants.CommonConstants.EXTRA_KEYS_KEY;
import static org.apache.dubbo.common.constants.CommonConstants.SHUTDOWN_WAIT_KEY;
import static org.apache.dubbo.common.constants.RegistryConstants.ENABLE_EMPTY_PROTECTION_KEY;
import static org.apache.dubbo.common.constants.RegistryConstants.REGISTER_MODE_KEY;