Hadoop - Reducer class in java

I am developing a Hadoop project in java. I want to find the customers with max consumption in a certain day. I have managed to find the customers in the date I want, but I am facing a problem in my Reducer class. Here is the code:

Mapper Class

import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.StringTokenizer;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;

public class alicanteMapperC extends
        Mapper<LongWritable, Text, Text, IntWritable> {

    String Customer = new String();
    SimpleDateFormat ft = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    Date t = new Date();
    IntWritable Consumption = new IntWritable();
    int counter = 0;

    //new vars
    int max=0;

    @Override
    public void map(LongWritable key, Text value, Context context)
            throws IOException, InterruptedException {

        Date d2 = null;
        try {
             d2 = ft.parse("2013-07-01 01:00:00");
        } catch (ParseException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }

        if (counter > 0) {

            String line = value.toString();
            StringTokenizer itr = new StringTokenizer(line, ",");

            while (itr.hasMoreTokens()) {
                Customer = itr.nextToken();
                try {
                    t = ft.parse(itr.nextToken());
                } catch (ParseException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                Consumption.set(Integer.parseInt(itr.nextToken()));
            }

            if (t.compareTo(d2) == 0) {
                context.write(new Text(Customer), Consumption);
            }
        }
        counter++;
    }
}

Reducer class

import java.io.IOException;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;

public class alicanteReducerC extends
        Reducer<Text, IntWritable, Text, IntWritable> {

    IntWritable maximum = new IntWritable();

    public void reduce(Text key, Iterable<IntWritable> values, Context context)
            throws IOException, InterruptedException {

        int max = 0;

        for (IntWritable val : values) {
            if (val.get() > max) {
                max = val.get();
            }
        }

        for (IntWritable val : values) {
            if (val.get() == max) {
                context.write(key, val);
            }
        }
    }
}

Do you have any idea why the reducer won't write to the output file? In other words, why doesn't the second for works?

EDIT In my mapper class I find the Customers in a specific date and thus the consumption of them and I pass these values in the reducer class.

In the reducer class I want to find the max consumption and the customer associated to this consumption.

Copyright Notice：Content Author:「Haris H」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/41617770/hadoop-reducer-class-in-java