- [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: xxx
* Operating System version: xxx
* Java version: xxx

### Steps to reproduce this issue

`org.apache.dubbo.remoting.etcd.jetcd.JEtcdClientWrapper#doClose`:

```
if (globalLeaseId > 0) {
        revokeLease(this.globalLeaseId);
}
```

should be change to :

```
if (globalLeaseId != 0) {
        revokeLease(this.globalLeaseId);
}
```


Pls. provide [GitHub address] to reproduce this issue.

### Expected Result

What do you expected from the above steps？

### Actual Result

What actually happens?

If there is an exception, please attach the exception trace:

```
Just put your stack trace here!
```

}
        } finally {
            // 
            keepAlive = null;
        }
    }
    private void clearKeepAlive() {
        cancelKeepAlive = true;
        failedRegistered.clear();
        cancelKeepAlive();
    }
    protected void doClose() {
        try {
            cancelKeepAlive = true;
            if (globalLeaseId > 0) {
                revokeLease(this.globalLeaseId);
            }
        } catch (Exception e) {
            logger.warn("revoke global lease '" + globalLeaseId + "' failed, registry: " + url, e);
        }
        try {
            if (started && future != null) {
                started = false;
                future.cancel(true);
                reconnectNotify.shutdownNow();
            }
        } catch (Exception e) {
            logger.warn("stop reconnect Notify failed, registry: " + url, e);
        }
        try {