SCB-361 fix access log compilation warning

[yhs0092]

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fix compilation warning in access log module.
warning in EventBus.java and MonitorManager.java will be fixed by zhengyangyong.

[zhengyangyong]

EventBus.java and MonitorManager.java fix PR is here #564

[coveralls]

Coverage remained the same at 87.247% when pulling 772da18 on yhs0092:clean_compilation_warning into 255f86e on apache:master.