Dear All,
I get the following NoSuchMethodException
Exception in thread "main" java.lang.NoSuchMethodException:
PositionCounter.main([Ljava.lang.String;)
at java.lang.Class.getMethod(Class.java:1605)
at org.apache.hadoop.util.RunJar.main(RunJar.java:150)
when running the following PositionCounter class:
public class PositionCounter {
@SuppressWarnings("deprecation")
public static class Map extends MapReduceBase implements
Mapper<LongWritable, Text, Text, IntWritable> {
public void map(LongWritable key, Text value,
OutputCollector<Text, IntWritable> output, Reporter reporter)
throws IOException {
String line = value.toString();
StringTokenizer tokenizer = new StringTokenizer(line);
for (int i = 0; i < line.length(); i++) {
String s = new StringBuilder().append(line.charAt(i)).toString();
output.collect(new Text(s), new IntWritable(i));
}
}
@SuppressWarnings("deprecation")
public static void main(String[] args) throws Exception {
JobConf conf = new JobConf(PositionCounter.class);
conf.setJobName("positioncounter");
conf.setOutputKeyClass(Text.class);
conf.setOutputValueClass(IntWritable.class);
conf.setMapperClass(Map.class);
// conf.setCombinerClass(Reduce.class);
//conf.setReducerClass(Reduce.class);
conf.setInputFormat(TextInputFormat.class);
conf.setOutputFormat(TextOutputFormat.class);
//conf.setNumReduceTasks(new Integer(1));
FileInputFormat.setInputPaths(conf, new Path(args[0]));
FileOutputFormat.setOutputPath(conf, new Path(args[1]));
JobClient.runJob(conf);
}
}
}
Any help is greatly appreciated,
Best,
Attila
On Thu, Nov 18, 2010 at 11:46 PM, Attila Csordas <attilacsor...@gmail.com>wrote:
> Dear All,
>
> Java, Hadoop rookie here coming from biology, more wet lab than dry lab so
> far.
>
> I'd like to build a mapper which emits (charAt(i), i+1) (in
> StandardStringJava not in HadoopTextJava) pairs from lines containing
> a sequence.
>
> Which is the more easier and obvious way to implement this: using Text
> and charAt() and IntWritable within the Mapper or build a
> CustomWritable class?
>
> Hints, not total solutions please (so I can write again if unable to
> figure it out shortly)
> Best,
> --
> Attila Csordas
> Bioinformatician
> EMBL European Bioinformatics Institute
> Wellcome Trust Genome Campus
> Hinxton, Cambridge, UK
>
