Question

Point out the wrong statement.

(a) DoFns also have a number of helper methods for working with Hadoop Counters, all named increment

(b) The Crunch APIs contain a number of useful subclasses of DoFn that handle common data processing scenarios and are easier to write and test

(c) FilterFn class defines a single abstract method

(d) None of the mentioned

I have been asked this question in unit test.

My question is from Crunch with Hadoop in chapter Apache Spark, Flume, Lucene, Hama, HCatalog, Mahout, Drill, Crunch and Thrift of Hadoop

Answer 1

The correct choice is (d) None of the mentioned

For explanation: Counters are an incredibly useful way of keeping track of the state of long-running data pipelines and detecting any exceptional conditions that occur during processing