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The following page has been changed by JackHebert:
http://wiki.apache.org/lucene-hadoop/HadoopMapReduceConfigureMethod

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== Mapper/Reducer Configure method ==

Both the Mapper and Reducer classes contain a method that can be overridden: 
public void configure(JobConf conf). 

This is called when the map/reduce task is instantiated rather than once per 
record. Data structures that need to be persistent across Map or Reduce calls 
can be created here, but note that they will NOT be shared across map or reduce 
tasks.

It is also possible to pass data to this method via the JobConf object. When 
the JobConf object is created the method JobConf.set(String name, Object value) 
can be used to set values for the mapper and reducer. During the configure 
method simply use JobConf.get(String name) to access the value previously set.

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