in java/dataproc-wordcount/src/main/java/com/example/bigtable/sample/WordCountHBase.java [74:80]
public void reduce(ImmutableBytesWritable key, Iterable<IntWritable> values, Context context)
throws IOException, InterruptedException {
int sum = sum(values);
Put put = new Put(key.get());
put.addColumn(COLUMN_FAMILY, COUNT_COLUMN_NAME, Bytes.toBytes(sum));
context.write(null, put);
}