MapRdeuce编程示例——词频统计一、MapRdeuce的词频统计的过程二、编程过程1、Mapper组件WordcountMapper.javapackagecom.itcast.mrdemo;importorg.apache.hadoop.io.IntWritable;importorg.apache.hadoop.io.LongWritable;importorg.apache.hadoop.io.Text;importorg.apache.hadoop.mapreduce.Mapper;importjava.io.IOException;/***Map需要指定四个泛型，用来限定