@Override
public void map(GenericRecord in, AvroCollector<Pair<Utf8, Long>> collector, Reporter reporter)
throws IOException {
Pair<Utf8, Long> p = new Pair<Utf8, Long>(PAIR_SCHEMA);
Utf8 shape = (Utf8) in.get("shape");
if (shape != null) {
p.set(shape, 1L);
collector.collect(p);
}
}
@Override
public int run(String[] args) throws Exception {
JobConf conf = new JobConf(getConf(), getClass());
conf.setJobName("UFO count");
String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
if (otherArgs.length != 2) {
System.err.println("Usage: avro UFO counter <in> <out>");
System.exit(2);
}
FileInputFormat.addInputPath(conf, new Path(otherArgs[0]));
Path outputPath = new Path(otherArgs[1]);
FileOutputFormat.setOutputPath(conf, outputPath);
outputPath.getFileSystem(conf).delete(outputPath);
Schema input_schema = Schema.parse(getClass().getResourceAsStream("ufo.avsc"));
AvroJob.setInputSchema(conf, input_schema);
AvroJob.setMapOutputSchema(
conf,
Pair.getPairSchema(Schema.create(Schema.Type.STRING), Schema.create(Schema.Type.LONG)));
AvroJob.setOutputSchema(conf, OUTPUT_SCHEMA);
AvroJob.setMapperClass(conf, AvroRecordMapper.class);
AvroJob.setReducerClass(conf, AvroRecordReducer.class);
conf.setInputFormat(AvroInputFormat.class);
JobClient.runJob(conf);
return 0;
}
public class AvroMR extends Configured implements Tool {
public static final Schema PAIR_SCHEMA =
Pair.getPairSchema(Schema.create(Schema.Type.STRING), Schema.create(Schema.Type.LONG));
public static final Schema OUTPUT_SCHEMA = ReflectData.get().getSchema(UFORecord.class);
@Override
public int run(String[] args) throws Exception {
JobConf conf = new JobConf(getConf(), getClass());
conf.setJobName("UFO count");
String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
if (otherArgs.length != 2) {
System.err.println("Usage: avro UFO counter <in> <out>");
System.exit(2);
}
FileInputFormat.addInputPath(conf, new Path(otherArgs[0]));
Path outputPath = new Path(otherArgs[1]);
FileOutputFormat.setOutputPath(conf, outputPath);
outputPath.getFileSystem(conf).delete(outputPath);
Schema input_schema = Schema.parse(getClass().getResourceAsStream("ufo.avsc"));
AvroJob.setInputSchema(conf, input_schema);
AvroJob.setMapOutputSchema(
conf,
Pair.getPairSchema(Schema.create(Schema.Type.STRING), Schema.create(Schema.Type.LONG)));
AvroJob.setOutputSchema(conf, OUTPUT_SCHEMA);
AvroJob.setMapperClass(conf, AvroRecordMapper.class);
AvroJob.setReducerClass(conf, AvroRecordReducer.class);
conf.setInputFormat(AvroInputFormat.class);
JobClient.runJob(conf);
return 0;
}
public static class AvroRecordMapper extends AvroMapper<GenericRecord, Pair<Utf8, Long>> {
@Override
public void map(GenericRecord in, AvroCollector<Pair<Utf8, Long>> collector, Reporter reporter)
throws IOException {
Pair<Utf8, Long> p = new Pair<Utf8, Long>(PAIR_SCHEMA);
Utf8 shape = (Utf8) in.get("shape");
if (shape != null) {
p.set(shape, 1L);
collector.collect(p);
}
}
}
public static class AvroRecordReducer extends AvroReducer<Utf8, Long, GenericRecord> {
public void reduce(
Utf8 key, Iterable<Long> values, AvroCollector<GenericRecord> collector, Reporter reporter)
throws IOException {
long sum = 0;
for (Long val : values) {
sum += val;
}
GenericRecord value = new GenericData.Record(OUTPUT_SCHEMA);
value.put("shape", key);
value.put("count", sum);
collector.collect(value);
}
}
public static void main(String[] args) throws Exception {
int res = ToolRunner.run(new Configuration(), new AvroMR(), args);
System.exit(res);
}
}