- [x] I have searched the [issues](https://github.com/apache/incubator-dubbo/issues) of this repository and believe that this is not a duplicate.
- [x] I have checked the [FAQ](https://github.com/apache/incubator-dubbo/blob/master/FAQ.md) of this repository and believe that this is not a duplicate.


### Environment

* Dubbo version: 2.7.2-SNAPSHOT
* Operating System version: windows1
* Java version: 1.8

### Steps to reproduce this issue
```java
public class RedisMetadataReport extends AbstractMetadataReport {

    private final static Logger logger = LoggerFactory.getLogger(RedisMetadataReport.class);

    final JedisPool pool;

    public RedisMetadataReport(URL url) {
        super(url);
        pool = new JedisPool(new JedisPoolConfig(), url.getHost(), url.getPort());
    }
}
```
I see the construct method used `JedisPool`, 
**if cluster ，how should  do？**

private static final long serialVersionUID = 55233L;
    /**
     * the value is : metadata-report
     */
    private static final String PREFIX_TAG = StringUtils.camelToSplitName(
            MetadataReportConfig.class.getSimpleName().substring(0, MetadataReportConfig.class.getSimpleName().length() - 6), PROPERTIES_CHAR_SEPERATOR);
    
    private String address;
    
    private String username;
    
    private String password;
    
    private Integer timeout;
    /**
     * The group the metadata in . It is the same as registry
     */
    private String group;
    
    private Map<String, String> parameters;
    private Integer retryTimes;
    private Integer retryPeriod;