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實作八 Lab 8

在完全分散模式下編譯 MapReduce 程式
Compiling Hadoop MapReduce Java Program in Hadoop Cluster

以下練習，請連線至 hdp01.3du.me 操作。底下的 userXX 等於您的用戶名稱。
以下練習，請連線至 hdp02.3du.me 操作。底下的 userXX 等於您的用戶名稱。
以下練習，請連線至 hdp03.3du.me 操作。底下的 userXX 等於您的用戶名稱。
以下練習，請連線至 hdp04.3du.me 操作。底下的 userXX 等於您的用戶名稱。

Practice 1 : Word Count (Basic)

• 上傳內容到 HDFS 內
  upload data to HDFS

  $ mkdir lab8_input
  $ echo "I like NCTU Cloud Course." > lab8_input/input1
  $ echo "I like nctu Cloud Course, and we enjoy this course." > lab8_input/input2
  $ hadoop fs -put lab8_input lab8_input
  $ hadoop fs -ls lab8_input
  Found 2 items
  -rw-r--r--   2 hXXXX supergroup         26 2011-04-19 10:07 /user/hXXXX/lab8_input/input1
  -rw-r--r--   2 hXXXX supergroup         52 2011-04-19 10:07 /user/hXXXX/lab8_input/input2
  

• 下載 ​WordCount.java 並存到家目錄;
  Download ​WordCount.java and save to your home directory

  ~$ wget http://www.classcloud.org/hadoop4win/WordCount.java
  

• 運作程式
  Compile WordCount.java and run it by hadoop jar command

$ mkdir MyJava
$ ln -s /opt/hadoop/hadoop-*-core.jar hadoop-core.jar
$ javac -classpath hadoop-core.jar -d MyJava WordCount.java
$ jar -cvf wordcount.jar -C MyJava .
$ hadoop jar wordcount.jar WordCount lab8_input/ lab8_out1/
$ hadoop fs -cat lab8_out1/part-00000

• lab8_out1 執行結果
  You should see results like this :

  Cloud 2
  Course, 1
  Course. 1
  I 2
  NCTU  1
  and 1
  course. 1
  enjoy 1
  like  2
  nctu  1
  this  1
  we  1
  

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