code: public void log(Level level, String msg, Throwable thrown) {
          if (level.intValue() < levelValue || levelValue == offValue) {
              return;
          }
          LogRecord lr = new LogRecord(level, msg);
          lr.setThrown(thrown);
          doLog(lr);
      }
docs: Log a message, with associated Throwable information.
  <p>
  If the logger is currently enabled for the given message
  level then the given arguments are stored in a LogRecord
  which is forwarded to all registered output handlers.
  <p>
  Note that the thrown argument is stored in the LogRecord thrown
  property, rather than the LogRecord parameters property.  Thus is it
  processed specially by output Formatters and is not treated
  as a formatting parameter to the LogRecord message property.
  <p>
  @param   level   One of the message level identifiers, e.g., SEVERE
  @param   msg     The string message (or a key in the message catalog)
  @param   thrown  Throwable associated with log message.