Difference between old API and new API?
->new API uses mapper and reducer as class and old API uses mapper and reducer as interface .
-> In new API ,both mapper and reducer can control the flow but in old API ,only mapper can control the flow by maprunable.
->job configurations are done through the jobconfiguration class and in OLD API it id done through jobconf.
->output file will be like part-00000 in OLD API both for mapper and reducer . In new API it will be like Part-m-000 for mapper and part-r-00 for reducers.
->we can find new API in org.apache.hadoop.mapreduce package .still we can find old API in org.apache.hadoop.mapred