code: public SourceType identifyWithEventName(String source, String eventName) {
          if (eventName.startsWith(CREATE_EVENT_PREFIX)) {
              return getCloudTrailSourceType(source);
          }
          return SourceType.Other;
      }
docs: Identify the source type with event action.
  @param source the S3 object name
  @param eventName the event name defined by Amazon S3.
  @return {@link SourceType}