@SuppressWarnings("unchecked")
  public static <K1,V1,K2,V2>
  Class<Mapper<K1,V1,K2,V2>> getMapperClass(JobContext job) {
    return (Class<Mapper<K1,V1,K2,V2>>) 
         job.getConfiguration().getClass("mapred.map.multithreadedrunner.class",
                                         Mapper.class);
  }
@ SuppressWarnings ( "unchecked" ) public static < K1 , V1 , K2 , V2 > Class < Mapper < K1 , V1 , K2 , V2 > > getMapperClass ( JobContext job ) { return ( Class < Mapper < K1 , V1 , K2 , V2 > > ) job . getConfiguration ( ) . getClass ( "mapred.map.multithreadedrunner.class" , Mapper . class ) ; }
Get the application's mapper class.
@param <K1> the map's input key type
@param <V1> the map's input value type
@param <K2> the map's output key type
@param <V2> the map's output value type
@param job the job
@return the mapper class to run