Issue 3597 fix sonar issues

[whuwb]

Fix 4 issues

IT :
[INFO] Apache Kylin ....................................... SUCCESS [ 8.032 s]
[INFO] Apache Kylin - Core Common ......................... SUCCESS [ 22.815 s]
[INFO] Apache Kylin - Core Metadata ....................... SUCCESS [01:00 min]
[INFO] Apache Kylin - Core Dictionary ..................... SUCCESS [05:56 min]
[INFO] Apache Kylin - Core Cube ........................... SUCCESS [01:25 min]
[INFO] Apache Kylin - Core Metrics ........................ SUCCESS [ 1.804 s]
[INFO] Apache Kylin - Core Job ............................ SUCCESS [ 47.911 s]
[INFO] Apache Kylin - Core Storage ........................ SUCCESS [ 10.086 s]
[INFO] Apache Kylin - MapReduce Engine .................... SUCCESS [ 26.941 s]
[INFO] Apache Kylin - Spark Engine ........................ SUCCESS [ 10.207 s]
[INFO] Apache Kylin - Hive Source ......................... SUCCESS [ 9.120 s]
[INFO] Apache Kylin - DataSource SDK ...................... SUCCESS [ 11.890 s]
[INFO] Apache Kylin - Jdbc Source ......................... SUCCESS [ 23.005 s]
[INFO] Apache Kylin - Kafka Source ........................ SUCCESS [ 5.681 s]
[INFO] Apache Kylin - Cache ............................... SUCCESS [ 13.945 s]
[INFO] Apache Kylin - HBase Storage ....................... SUCCESS [ 22.400 s]
[INFO] Apache Kylin - Query ............................... SUCCESS [ 13.606 s]
[INFO] Apache Kylin - Metrics Reporter Hive ............... SUCCESS [ 1.119 s]
[INFO] Apache Kylin - Metrics Reporter Kafka .............. SUCCESS [ 0.806 s]
[INFO] Apache Kylin - REST Server Base .................... SUCCESS [ 31.671 s]
[INFO] Apache Kylin - REST Server ......................... SUCCESS [01:31 min]
[INFO] Apache Kylin - JDBC Driver ......................... SUCCESS [ 11.575 s]
[INFO] Apache Kylin - Assembly ............................ SUCCESS [ 16.330 s]
[INFO] Apache Kylin - Tool ................................ SUCCESS [ 11.979 s]
[INFO] Apache Kylin - Tool Assembly ....................... SUCCESS [ 3.672 s]
[INFO] Apache Kylin - Integration Test .................... SUCCESS [ 04:38 h]
[INFO] Apache Kylin - Tomcat Extension .................... SUCCESS [ 2.588 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 04:53 h
[INFO] Finished at: 2018-12-07T07:44:16Z
[INFO] ------------------------------------------------------------------------

[asfgit]

Can one of the admins verify this patch?

[shaofengshi]

LGTM