hadoop-2.7.1伪分布式模式下命令行运行java文件(hadoop权威指南学习篇)

时间:2022-11-09 13:32:11

原文来自 http://blog.csdn.net/yutianzuijin/article/details/9457431 

上文针对hadoop-1.1.2用命令行运行了wordcount, 本文在hadoop-2.7.1平台下运行了《hadoop权威指南:第三版》中的URLCat实例(3.5.1节)


1. hadoop-2.7.1伪分布模式安装请看 点击打开链接

2. 利用eclipse或inteliij编写并编译URLCat.java文件,生成URLCat.class

3. 此时直接运行将会出现“错误: 找不到或无法加载主类 URLCat”,需要将class文件打包成jar:   

   $ jar cvf URLCat.jar  URLCat.class
4. 运行:

$bin/hadoop jar URLCat.jar URLCat hdfs://localhost/user/shentao/quangle.txt 
On the top of the Crumpetty Tree
The Quangle Wangle sat,
But his face you could not see,
On account of his Beaver Hat.