The Hadoop Java API for MapReduce

Hadoop underwent a major API change in its 0.20 release, which is the primary interface in the 1.0 version we use in this book. Though the prior API was certainly functional, the community felt it was unwieldy and unnecessarily complex in some regards.

The new API, sometimes generally referred to as context objects, for reasons we'll see later, is the future of Java's MapReduce development; and as such we will use it wherever possible in this book. Note that caveat: there are parts of the pre-0.20 MapReduce libraries that have not been ported to the new API, so we will use the old interfaces when we need to examine any of these.

The 0.20 MapReduce Java API

The 0.20 and above versions of MapReduce API have most of ...

Get Hadoop: Data Processing and Modelling now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.