code: private static void logToken(final Level logLevel, final String msgPrefix, final UserGroupInformation user) {
      if (LOG.isLoggable(logLevel)) {
        LOG.log(logLevel, "{0} number of tokens: [{1}].",
            new Object[] {msgPrefix, user.getCredentials().numberOfTokens()});
        for (final org.apache.hadoop.security.token.Token t : user.getCredentials().getAllTokens()) {
          LOG.log(logLevel, "Token service: {0}, token kind: {1}.", new Object[] {t.getService(), t.getKind()});
        }
      }
    }
docs: Log all the tokens in the container for thr user.
  
  @param logLevel - the log level.
  @param msgPrefix - msg prefix for log.
  @param user - the UserGroupInformation object.