void init() {
    String rootLoggerDirectory = getRootLoggerDirectory();
    if (rootLoggerDirectory == null) {
        return;
    }
    String absolutePath = new File(rootLoggerDirectory, failedMessageFile).getAbsolutePath();
    try {
        DailyRollingFileAppender failedLogFilesAppender = new DailyRollingFileAppender(
                new PatternLayout(PATTERN_SPEC_TIMESTAMP_MESSAGE_NEWLINE), absolutePath, DATE_PATTERN);
        logger.addAppender(failedLogFilesAppender);
        logger.setLevel(Level.ERROR);
        logger.setAdditivity(false);
    } catch (IOException e) {
        e.printStackTrace();
    }
}
 

void init() {
    String rootLoggerDirectory = getRootLoggerDirectory();
    if (rootLoggerDirectory == null) {
        return;
    }
    String absolutePath = new File(rootLoggerDirectory, failedMessageFile).getAbsolutePath();
    try {
        DailyRollingFileAppender failedLogFilesAppender = new DailyRollingFileAppender(
                new PatternLayout(PATTERN_SPEC_TIMESTAMP_MESSAGE_NEWLINE), absolutePath, DATE_PATTERN);
        logger.addAppender(failedLogFilesAppender);
        logger.setLevel(Level.ERROR);
        logger.setAdditivity(false);
    } catch (IOException e) {
        e.printStackTrace();
    }
}
 

boolean init(FairSchedulerConfiguration conf) {
  if (conf.isEventLogEnabled()) {
    try {
      logDir = conf.getEventlogDir();
      File logDirFile = new File(logDir);
      if (!logDirFile.exists()) {
        if (!logDirFile.mkdirs()) {
          throw new IOException(
              "Mkdirs failed to create " + logDirFile.toString());
        }
      }
      String username = System.getProperty("user.name");
      logFile = String.format("%s%shadoop-%s-fairscheduler.log",
          logDir, File.separator, username);
      logDisabled = false;
      PatternLayout layout = new PatternLayout("%d{ISO8601}\t%m%n");
      appender = new DailyRollingFileAppender(layout, logFile, "'.'yyyy-MM-dd");
      appender.activateOptions();
      LOG.info("Initialized fair scheduler event log, logging to " + logFile);
    } catch (IOException e) {
      LOG.error(
          "Failed to initialize fair scheduler event log. Disabling it.", e);
      logDisabled = true;
    }
  } else {
    logDisabled = true;
  }
  return !(logDisabled);
}
 

boolean init(FairSchedulerConfiguration conf) {
  if (conf.isEventLogEnabled()) {
    try {
      logDir = conf.getEventlogDir();
      File logDirFile = new File(logDir);
      if (!logDirFile.exists()) {
        if (!logDirFile.mkdirs()) {
          throw new IOException(
              "Mkdirs failed to create " + logDirFile.toString());
        }
      }
      String username = System.getProperty("user.name");
      logFile = String.format("%s%shadoop-%s-fairscheduler.log",
          logDir, File.separator, username);
      logDisabled = false;
      PatternLayout layout = new PatternLayout("%d{ISO8601}\t%m%n");
      appender = new DailyRollingFileAppender(layout, logFile, "'.'yyyy-MM-dd");
      appender.activateOptions();
      LOG.info("Initialized fair scheduler event log, logging to " + logFile);
    } catch (IOException e) {
      LOG.error(
          "Failed to initialize fair scheduler event log. Disabling it.", e);
      logDisabled = true;
    }
  } else {
    logDisabled = true;
  }
  return !(logDisabled);
}
 

private Appender buildAppender(String name, String fileName, String pattern) {
    DailyRollingFileAppender appender = new DailyRollingFileAppender();
    appender.setName(name);
    appender.setAppend(true);
    appender.setEncoding(getEncoding());
    appender.setLayout(new PatternLayout(pattern));
    appender.setFile(new File(getLogPath(), fileName).getAbsolutePath());
    appender.activateOptions();// 很重要，否则原有日志内容会被清空
    return appender;
}
 

private Appender buildAppender(String name, String fileName, String pattern) {
    DailyRollingFileAppender appender = new DailyRollingFileAppender();
    appender.setName(name);
    appender.setAppend(true);
    appender.setEncoding(getEncoding());
    appender.setLayout(new PatternLayout(pattern));
    appender.setFile(new File(getLogPath(), fileName).getAbsolutePath());
    appender.activateOptions();// 很重要，否则原有日志内容会被清空
    return appender;
}