MapReduce mapper interface processes input into key-value pairs to generate a set of intermediate key-value pairs to be sent for further refining and extraction of the data.
public interface IMapper : IDisposable
|Map(Object, Object, IOutputMap)||
This method will contain the logic to map the input from cache into more meaningful and goal specific key-value pairs which can be sent to the Reducer or optional Combiner.
Referring to the workflow diagram, the string input is transformed by emitting each word with a key-value pair in the Mapper.