Hadoop Streaming allows developers to use virtually any programming language to create MapReduce jobs, but it’s a bit of a kludge. The MapReduce programming environment needs to be pluggable.

MapReduce的并行处理模式给自己增添了各种问题。 虽然Java常用于MapReduce程序，你不见得非要成为Java专家才能享受到Hadoop上MapReduce的好处。 三种 MapReduce开发的替代方法包括Pig, streaming MapReduce和域特定语言，比如Scalding。 Pig是一种Hadoop下不借助Java而处理大数据的平台。

At its core, MapReduce is a combination of two functions — map() and reduce(), as its name would suggest. A quick look at a sample Java program will help you get your bearings in MapReduce.

A Tutorial for Hadoop and Map Reduce in Java - SiliconANGLEThe code implements a dictionary translation by taking a series of compiled dictionaries (English-Spanish, English-Italian, English ...

Pig bridges the gap between Hadoop Hive and Hadoop MapReduce Java programming. It is nowhere near as simple or familiar as Hive’s SQL dialect; but, it can be used to create more complex multi-step ...