Write Key-Value Fields to MapWriter
Updated: Aug 28, 2026
package com.northconcepts.datapipeline.examples.cookbook;
import java.io.File;
import java.util.HashMap;
import java.util.Map;
import com.northconcepts.datapipeline.core.DataReader;
import com.northconcepts.datapipeline.core.DataWriter;
import com.northconcepts.datapipeline.csv.CSVReader;
import com.northconcepts.datapipeline.job.Job;
import com.northconcepts.datapipeline.memory.MapWriter;
public class WriteKeyValueFieldsToMapWriter {
public static void main(String[] args) {
DataReader reader = new CSVReader(new File("example/data/input/countries_with_country-code.csv"))
.setFieldNamesInFirstRow(true);
Map countryCodeMap = new HashMap<>();
//Create MapWriter, specify key, value and map
DataWriter writer = new MapWriter("Country", "Country code", countryCodeMap);
Job.run(reader, writer);
for (Map.Entry entry : countryCodeMap.entrySet()) {
System.out.println(entry.getKey() + " --> " + entry.getValue());
}
}
}
