hi i wanted to know the basic difference between jobconf and job objects,currently i am submitting my job like this
i saw other way of submitting jobs like this
Configuration conf = getConf(); Job job = new Job(conf, "secondary sort"); job.waitForCompletion(true); return 0;
and how can i specify the sortcomparator class for the job using jobconf?
can any one explain me this concept?
JobConf and everything else in the
org.apache.hadoop.mapred package is part of the old API used to write hadoop jobs,
Job and everything in the
org.apache.hadoop.mapreduce package is part of the new and preferred API to write hadoop jobs. Both APIs generally provide equivalent core functionality.
If you're new to hadoop just start using the new API (i.e.
Configuration instead of
JobConf). Make sure to not import anything from the
mapred package. When you find examples on the internet using the old API you can use this presentation or this guide to translate it to the new API.