Hadoop入门学习之二：一步一步运行WordCount

WordCount是学习Hadoop的经典入门范例。下面通过一步步的操作，来编译、打包、运行WordCount程序。
1、在Hadoop 1.0.4的解压目录的如下位置可以找到WordCount.java的源文件
src/examples/org/apache/hadoop/examples/WordCount.java
2、新建一个dev的文件夹，将WordCount.java拷贝至dev/wordcount文件夹下

ubuntu@ubuntu:~/dev/wordcount$ pwd
/home/ubuntu/dev/wordcount
ubuntu@ubuntu:~/dev/wordcount$ ls
bin  compile.txt  WordCount.java

3、在dev/wordcount文件夹下创建一个bin文件夹，并将编译WordCount.java得到的class文件生成至bin文件夹下
javac -classpath /home/ubuntu/hadoop-1.0.4/hadoop-core-1.0.4.jar:/home/ubuntu/hadoop-1.0.4/lib/commons-cli-1.2.jar -d bin WordCount.java
4、将生成的class文件打包成jar包
jar -cvf WordCount.jar *.class
5、在bin下新建一个input文件夹，并生成两个输入文件

ubuntu@ubuntu:~/dev/wordcount/bin/input$ ls
words-1.txt  words-2.txt
ubuntu@ubuntu:~/dev/wordcount/bin/input$ cat words-1.txt 
i am a student!
how are you?
my name is lily.