Java TaskAttemptContext.progress方法代碼示例

import org.apache.hadoop.mapreduce.TaskAttemptContext; //導入方法依賴的package包/類
@Private
public void commitTask(TaskAttemptContext context, Path taskAttemptPath) 
    throws IOException {

  TaskAttemptID attemptId = context.getTaskAttemptID();
  if (hasOutputPath()) {
    context.progress();
    if(taskAttemptPath == null) {
      taskAttemptPath = getTaskAttemptPath(context);
    }
    FileSystem fs = taskAttemptPath.getFileSystem(context.getConfiguration());
    FileStatus taskAttemptDirStatus;
    try {
      taskAttemptDirStatus = fs.getFileStatus(taskAttemptPath);
    } catch (FileNotFoundException e) {
      taskAttemptDirStatus = null;
    }

    if (taskAttemptDirStatus != null) {
      if (algorithmVersion == 1) {
        Path committedTaskPath = getCommittedTaskPath(context);
        if (fs.exists(committedTaskPath)) {
           if (!fs.delete(committedTaskPath, true)) {
             throw new IOException("Could not delete " + committedTaskPath);
           }
        }
        if (!fs.rename(taskAttemptPath, committedTaskPath)) {
          throw new IOException("Could not rename " + taskAttemptPath + " to "
              + committedTaskPath);
        }
        LOG.info("Saved output of task '" + attemptId + "' to " +
            committedTaskPath);
      } else {
        // directly merge everything from taskAttemptPath to output directory
        mergePaths(fs, taskAttemptDirStatus, outputPath);
        LOG.info("Saved output of task '" + attemptId + "' to " +
            outputPath);
      }
    } else {
      LOG.warn("No Output found for " + attemptId);
    }
  } else {
    LOG.warn("Output Path is null in commitTask()");
  }
}
 

import org.apache.hadoop.mapreduce.TaskAttemptContext; //導入方法依賴的package包/類
@Private
public void abortTask(TaskAttemptContext context, Path taskAttemptPath) throws IOException {
  if (hasOutputPath()) { 
    context.progress();
    if(taskAttemptPath == null) {
      taskAttemptPath = getTaskAttemptPath(context);
    }
    FileSystem fs = taskAttemptPath.getFileSystem(context.getConfiguration());
    if(!fs.delete(taskAttemptPath, true)) {
      LOG.warn("Could not delete "+taskAttemptPath);
    }
  } else {
    LOG.warn("Output Path is null in abortTask()");
  }
}
 

import org.apache.hadoop.mapreduce.TaskAttemptContext; //導入方法依賴的package包/類
@Override
public void recoverTask(TaskAttemptContext context)
    throws IOException {
  if(hasOutputPath()) {
    context.progress();
    TaskAttemptID attemptId = context.getTaskAttemptID();
    int previousAttempt = getAppAttemptId(context) - 1;
    if (previousAttempt < 0) {
      throw new IOException ("Cannot recover task output for first attempt...");
    }

    Path previousCommittedTaskPath = getCommittedTaskPath(
        previousAttempt, context);
    FileSystem fs = previousCommittedTaskPath.getFileSystem(context.getConfiguration());
    if (LOG.isDebugEnabled()) {
      LOG.debug("Trying to recover task from " + previousCommittedTaskPath);
    }
    if (algorithmVersion == 1) {
      if (fs.exists(previousCommittedTaskPath)) {
        Path committedTaskPath = getCommittedTaskPath(context);
        if (fs.exists(committedTaskPath)) {
          if (!fs.delete(committedTaskPath, true)) {
            throw new IOException("Could not delete "+committedTaskPath);
          }
        }
        //Rename can fail if the parent directory does not yet exist.
        Path committedParent = committedTaskPath.getParent();
        fs.mkdirs(committedParent);
        if (!fs.rename(previousCommittedTaskPath, committedTaskPath)) {
          throw new IOException("Could not rename " + previousCommittedTaskPath +
              " to " + committedTaskPath);
        }
      } else {
          LOG.warn(attemptId+" had no output to recover.");
      }
    } else {
      // essentially a no-op, but for backwards compatibility
      // after upgrade to the new fileOutputCommitter,
      // check if there are any output left in committedTaskPath
      if (fs.exists(previousCommittedTaskPath)) {
        LOG.info("Recovering task for upgrading scenario, moving files from "
            + previousCommittedTaskPath + " to " + outputPath);
        FileStatus from = fs.getFileStatus(previousCommittedTaskPath);
        mergePaths(fs, from, outputPath);
      }
      LOG.info("Done recovering task " + attemptId);
    }
  } else {
    LOG.warn("Output Path is null in recoverTask()");
  }
}