code: public static boolean isSLF4jAvailable() {
          if (SLF4jAvailable == null) {
              try {
                  Class.forName("org.slf4j.Logger");
                  setSLF4jAvailable(true);
              } catch (ClassNotFoundException e) {
                  setSLF4jAvailable(false);
              }
          }
  
          return SLF4jAvailable;
      }
docs: Checks if SLF4j is available (loaded) in JVM
  
  @return true - if SLF4j is available for use