code: protected void warnSQLFailureState(SQLFailureException cause) {
          if (cause instanceof EntityAlreadyExistsException) {
              return; // the exception is obviously application exception so no warning
          }
          try {
              final String msg = buildSQLFailureState(cause);
              logger.warn(msg); // only warning here, the cause will be caught by logging filter
          } catch (RuntimeException continued) {
              logger.info("Failed to show warning of SQL failure state: " + Integer.toHexString(cause.hashCode()), continued);
          }
      }
docs: =================