我正在尝试对声纳法进行代码分析。但是，运行时出现错误
mvm声纳：声纳
这是错误消息：
[ERROR] SonarQube server [http://localhost:9000] can not be reached
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 42.972 s
[INFO] Finished at: 2017-06-06T08:51:52+08:00
[INFO] Final Memory: 8M/19M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.sonarsource.scanner.maven:sonar-maven-plugin:
3.3.0.603:sonar (default-cli) on project example-java-maven: Unable to execute SonarQube:
Fail to get bootstrap index from server: Status returned by url
[http://localhost:9000/batch/index] is not valid: [504] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven …sonarqube ×1