1. non-simplify mode:
```
dubbo://120.0.0.1:20880/org.apache.dubbo.demo.DemoService?key=value
```
the store path of ZK will be: `/dubbo/porg.apache.dubbo.demo.DemoService/url`

2. simplify mode:
```
dubbo://120.0.0.1:20880/org.apache.dubbo.demo.DemoService?key=value
```
the store path of ZK will be: `/dubbo/porg.apache.dubbo.demo.DemoService/url`

3. simplify mode with path specified:
```
dubbo://120.0.0.1:20880/path-value?key=value
```
the store path of ZK will be: `/dubbo/path-value/url`
buf.append("?");
                        }
                        first = false;
                    } else {
                        buf.append("&");
                    }
                    buf.append(entry.getKey());
                    buf.append("=");
                    buf.append(entry.getValue() == null ? "" : entry.getValue().trim());
                }
            }
        }
    }
    private String buildString(boolean appendUser, boolean appendParameter, String... parameters) {
        return buildString(appendUser, appendParameter, false, false, parameters);
    }
    private String buildString(boolean appendUser, boolean appendParameter, boolean useIP, boolean useService, String... parameters) {
        StringBuilder buf = new StringBuilder();
        if (StringUtils.isNotEmpty(protocol)) {
            buf.append(protocol);
            buf.append("://");
        }
        if (appendUser && StringUtils.isNotEmpty(username)) {
            buf.append(username);
            if (password != null && password.length() > 0) {
                buf.append(":");
                buf.append(password);
            }
            buf.append("@");
        }