code: public SLF4JQueryCountLoggingServletFilter buildSlf4jFilter(SLF4JLogLevel logLevel) {
          if (logLevel != null) {
              this.slf4jLogLevel = logLevel;
          }
  
          SLF4JQueryCountLoggingServletFilter filter = new SLF4JQueryCountLoggingServletFilter();
          if (this.slf4jLogLevel != null) {
              filter.setLogLevel(this.slf4jLogLevel);
          }
          filter.setWriteAsJson(this.writeAsJson);
          return filter;
      }
docs: Build {@link net.ttddyy.dsproxy.support.SLF4JQueryCountLoggingServletFilter}.
  
  @param logLevel slf4j log level
  @return query-count-logger using slf4j