Time for action – using ChainMapper for field validation/analysis

Let's use this principle and employ the ChainMapper class to help us provide some record validation within our job:

  1. Create the following class as UFORecordValidationMapper.java:
    import java.io.IOException; import org.apache.hadoop.io.* ; import org.apache.hadoop.mapred.* ; import org.apache.hadoop.mapred.lib.* ; public class UFORecordValidationMapper extends MapReduceBase implements Mapper<LongWritable, Text, LongWritable, Text> { public void map(LongWritable key, Text value, OutputCollector<LongWritable, Text> output, Reporter reporter) throws IOException { String line = value.toString(); if (validate(line)) output.collect(key, value); } private boolean validate(String str) { String[] ...

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