PrepAway - Latest Free Exam Questions & Answers

What is a Writable?

What is a Writable?

PrepAway - Latest Free Exam Questions & Answers

A.
Writable is an interface that all keys and values in MapReduce must implement. Classes
implementing this interface must implement methods for serializing and deserializing themselves.

B.
Writable is an abstract class that all keys and values in MapReduce must extend. Classes
extending this abstract base class must implement methods for serializing and deserializing
themselves

C.
Writable is an interface that all keys, but not values, in MapReduce must implement. Classes
implementing this interface must implement methods for serializing and deserializing themselves.

D.
Writable is an abstract class that all keys, but not values, in MapReduce must extend. Classes
extending this abstract base class must implement methods for serializing and deserializing
themselves.

Explanation:
public interface Writable
A serializable object which implements a simple, efficient, serialization protocol, based on
DataInput and DataOutput.
Any key or value type in the Hadoop Map-Reduce framework implements this interface.
Implementations typically implement a static read(DataInput) method which constructs a new
instance, calls readFields(DataInput) and returns the instance.
Reference: org.apache.hadoop.io,Interface Writable

3 Comments on “What is a Writable?

  1. Ramesh Hiremath says:

    A.
    Writable is an interface that all keys and values in MapReduce must implement. Classes
    implementing this interface must implement methods for serializing and deserializing themselves.




    0



    0

Leave a Reply

Your email address will not be published. Required fields are marked *