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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "HadoopMapReduce" by DanielTunkelang
Date Thu, 09 Jul 2009 04:08:52 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change notification.

The following page has been changed by DanielTunkelang:
http://wiki.apache.org/hadoop/HadoopMapReduce

The comment on the change is:
updated link to deprecated InputFormat class

------------------------------------------------------------------------------
  When an individual map task starts it will open a new output
  writer per configured reduce task. It will then proceed to read
  its !FileSplit using the [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/mapred/RecordReader.html
RecordReader] it gets from the specified
- [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/mapred/InputFormat.html
InputFormat]. !InputFormat parses the input and generates
+ [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/mapreduce/InputFormat.html
InputFormat]. !InputFormat parses the input and generates
  key-value pairs. !InputFormat must also handle records that may be split on the !FileSplit
boundary. For example [http://svn.apache.org/viewcvs.cgi/hadoop/core/trunk/src/mapred/org/apache/hadoop/mapred/TextInputFormat.java?view=markup
TextInputFormat] will read the last line of the !FileSplit past the split boundary and, when
reading other than the first !FileSplit, !TextInputFormat ignores the content up to the first
newline.
  
  It is not necessary for the !InputFormat to

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