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實作二十二 Lab22

透過 MapReduce 的設定檔傳遞參數
Passing Arguments to Mapper and Reducer with Configuration

請先連線至 nodeN.3du.me , N 為您的報名編號

cd ~/hadoop_labs/lab013
ant
hadoop fs -put l13_input l13_input
hadoop jar WordCount.jar l13_input l13_output
hadoop fs -cat l13_output/part-r-00000
hadoop jar WordCount.jar -Dwordcount.case.sensitive=false l13_input l13_output2
hadoop fs -cat l13_output2/part-r-00000

• Reference:
  • ​http://hadoop.apache.org/docs/r1.0.4/api/org/apache/hadoop/conf/Configuration.html
    • org.apache.hadoop.conf.Configuration.setBoolean(String name, boolean value)
    • org.apache.hadoop.conf.Configuration.getBoolean(String name, boolean defaultValue)
  • ​org.apache.hadoop.mapreduce.Mapper.setup(Mapper.Context context)
  • ​org.apache.hadoop.mapreduce.JobContext.getConfiguration()
  • ​http://www.cloudera.com/content/cloudera-content/cloudera-docs/HadoopTutorial/CDH4/Hadoop-Tutorial/ht_topic_7_1.html

實作習題

<問題 1>