What's this?(English)
In order to Learn Hadoop-MapReduce and do some improvements, I spent several monthes on Hadoop-0.23 source code.
Finally I found Hadoop 0.20(as well as 1.0 stable version) is more suitable for my work. I gave up Hadoop-0.23 although I have added almost 6000 lines comments on the MapReduce-Project part.
I decide to publish my comments to help people interested in Hadoop-Mapreduce and wanted to learn it via reading source code.
That's all.
关于这些代码（中文）
最初我打算在Hadoop0.23这个分支上做一些优化，后来由于种种原因（0.23更新太快、不稳定、LOG等不完善...），我觉得Hadoop 0.20（1.0的稳定版就是基于0.20）更适合我的工作。于是我放弃了0.23转向了0.20。
但前期在Hadoop0.23花费了很大精力，对Mapreduce部分做了一些注释，git diff 的结果有近6500行。
我打算把我注释过的代码托管在github上，供对MapReduce感兴趣的朋友参考，共同交流学习。