Okay.... I think I am down to my last problem. I have a 'AvroMapper' & a
'NonAvroReducer'. The Reducer is defined as follows:
private static class NonAvroReducer
extends MapReduceBase
implements Reducer<AvroKey<Utf8>, AvroValue<MyClass>, Text,
Text> {
I keep getting this in the Reduce step:
java.lang.ClassCastException: com.xyz.MyAvroProcessor$MyClass cannot be
cast to org.apache.avro.generic.IndexedRecord
at org.apache.avro.generic.GenericData.setField(GenericData.java:463)
at
org.apache.avro.generic.GenericDatumReader.readRecord(GenericDatumReader.java:166)
But 'MyClass' is just a Java Bean that I want to use to pass data between
Mapper & Reducer. Why do I have to implement IndexedRecord?
Please help. Thanks.
On Wed, Nov 16, 2011 at 11:20 PM, Something Something <
[email protected]> wrote:
> Sorry. Don't worry about this for now. Made progress. The input AVRO
> file was bad. Thanks.
>
>
> On Wed, Nov 16, 2011 at 11:13 PM, Sudharsan Sampath <[email protected]>wrote:
>
>> What's the output logs from your job..
>>
>>
>> On Thu, Nov 17, 2011 at 5:30 AM, Something Something <
>> [email protected]> wrote:
>>
>>> Why could this not be working? Any ideas? I even put a 'throw new
>>> RuntimeException' to see if it's coming to the Mapper, but it isn't.
>>> Thanks for the help.
>>>
>>> Code snippet:
>>>
>>>
>>>
>>> public static class MapImpl extends AvroMapper<Utf8, Pair<Utf8,
>>> Long>> {
>>>
>>> @Override
>>>
>>> public void map(Utf8 text, AvroCollector<Pair<Utf8, Long>>
>>> collector,
>>>
>>> Reporter reporter) throws IOException {
>>>
>>> throw new RuntimeException("my text: " + text.toString());
>>>
>>> // System.out.println("my text" + text);
>>>
>>> //
>>>
>>> // collector.collect(new Pair<Utf8, Long>(text, 1L));
>>>
>>> }
>>>
>>> }
>>>
>>>
>>>
>>> private static class NonAvroReducer
>>>
>>> extends MapReduceBase
>>>
>>> implements Reducer<AvroKey<Utf8>, AvroValue<Long>, Text,
>>> Text> {
>>>
>>>
>>> public void reduce(AvroKey<Utf8> key, Iterator<AvroValue<Long>>
>>> values,
>>>
>>> OutputCollector<Text, Text> out,
>>>
>>> Reporter reporter) throws IOException {
>>>
>>> out.collect(new Text(key.toString()),
>>>
>>> new Text("Testing"));
>>>
>>> while (values.hasNext()) {
>>>
>>> AvroValue<Long> value = values.next();
>>>
>>> out.collect(new Text(key.toString()),
>>>
>>> new Text(value.datum().toString()));
>>>
>>> }
>>>
>>> }
>>>
>>> }
>>>
>>>
>>> public static void main(String[] args) throws Exception {
>>>
>>>
>>>
>>> String dir = "/user/mydir";
>>>
>>>
>>>
>>> JobConf job = new JobConf(new Configuration(),
>>> TestAvroProcessor.class);
>>>
>>> job.setJobName(TestAvroProcessor.class.getName());
>>>
>>>
>>>
>>> Path outputPath = new Path(dir + "/out");
>>>
>>>
>>> outputPath.getFileSystem(job).delete(outputPath);
>>>
>>>
>>>
>>> AvroJob.setInputSchema(job, Schema.parse(new File(
>>> "/Users/mydir/profiles.json")));
>>>
>>> AvroJob.setOutputSchema(job, SCHEMA);
>>>
>>>
>>> AvroJob.setMapperClass(job, MapImpl.class);
>>>
>>>
>>> FileInputFormat.setInputPaths(job, new Path(dir + "/data"));
>>>
>>> FileOutputFormat.setOutputPath(job, outputPath);
>>>
>>> FileOutputFormat.setCompressOutput(job, false);
>>>
>>>
>>>
>>> job.setReducerClass(NonAvroReducer.class);
>>>
>>> job.setOutputFormat(TextOutputFormat.class);
>>>
>>> job.setOutputKeyClass(Text.class);
>>>
>>> job.setOutputValueClass(Text.class);
>>>
>>>
>>>
>>> JobClient.runJob(job);
>>>
>>>
>>>
>>>
>>>
>>> }
>>>
>>>
>>>
>>>
>>> On Tue, Nov 15, 2011 at 5:12 PM, Doug Cutting <[email protected]>wrote:
>>>
>>>> On 11/15/2011 03:16 PM, Something Something wrote:
>>>> > Quick question. I want the output from AvroJob.setReducerClass to be
>>>> in
>>>> > regular Text files - not in AVRO format. Can I do that? Any
>>>> examples?
>>>> > Sorry, kinda short on time to do research. Thanks.
>>>>
>>>> On the previously cited documentation page:
>>>>
>>>>
>>>> http://avro.apache.org/docs/current/api/java/org/apache/avro/mapred/package-summary.html
>>>>
>>>> Look for the text, "For jobs whose input is an Avro data file and which
>>>> use an AvroMapper, but whose reducer is a non-Avro Reducer and whose
>>>> output is a non-Avro format".
>>>>
>>>> A sample of a job that does this is at:
>>>>
>>>> http://s.apache.org/MsG
>>>>
>>>> Just use TextOutputFormat instead of SequenceFileOutputFormat.
>>>>
>>>> Doug
>>>>
>>>
>>>
>>
>
