Demos of various uses of the Java Mapper API
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Demonstrates a bunch of useful Mappers for use with the App Engine Mapreduce library

The Mapper library can be found here:

This project includes sample code for using the Java version of this
library. Code samples include:

- Changing all Strings to lowercase across all Entities
- Changing all Strings to lowercase across all Entities using a mutation pool (more efficient)
- Deleting all Entities of a given Kind
- Counting all the words across all Entities, then using a callback URL to save them
- Taking an input in the Mapper interface
- Importing data from a CSV file into the datastore

The introductory blog post to the Mapper API can be found here:

A follow up post about reading input from the Blobstore can be found here: