Hi Bejoy 1. Old API: The Map and Reduce classes are the same as in the example, the main method is as follows
public static void main(String[] args) throws IOException, InterruptedException { UserGroupInformation ugi = UserGroupInformation.createProxyUser("<remote user name>", UserGroupInformation.getLoginUser()); ugi.doAs(new PrivilegedExceptionAction<Void>() { public Void run() throws Exception { JobConf conf = new JobConf(WordCount.class); conf.setJobName("wordcount"); 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); FileInputFormat.setInputPaths(conf, new Path("<path to input dir>")); FileOutputFormat.setOutputPath(conf, new Path("<path to output dir>")); conf.set("mapred.job.tracker", "<ip:8021>"); FileSystem fs = FileSystem.get(new URI("hdfs://<ip>:8020"), new Configuration()); fs.mkdirs(new Path("<remote path>")); fs.copyFromLocalFile(new Path("<local path>/test.jar"), new Path("<remote path>")); DistributedCache.addArchiveToClassPath(new Path("<remote path>/test.jar"), conf, fs); JobClient.runJob(conf); return null; } }); } It works fine 2. New API: public class WordCountNewAPI { public static class WordCountMapper extends Mapper<LongWritable, Text, Text, IntWritable> { private final static IntWritable ONE = new IntWritable(1); private Text word = new Text(); @Override protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { String line = value.toString(); StringTokenizer tokenizer = new StringTokenizer(line); while (tokenizer.hasMoreTokens()) { word.set(tokenizer.nextToken()); context.write(word, ONE); } super.map(key, value, context); } } public static class WordCountReducer extends Reducer<Text, IntWritable, Text, IntWritable> { @Override protected void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException { int sum = 0; Iterator<IntWritable> iter = values.iterator(); while (iter.hasNext()) { sum += iter.next().get(); } context.write(key, new IntWritable(sum)); super.reduce(key, values, context); } } /** * @param args * @throws IOException * @throws InterruptedException */ public static void main(String[] args) throws IOException, InterruptedException { UserGroupInformation ugi = UserGroupInformation.createProxyUser("<remote user name>", UserGroupInformation.getLoginUser()); ugi.doAs(new PrivilegedExceptionAction<Void>() { public Void run() throws Exception { Configuration conf = new Configuration(); conf.set("mapred.job.tracker", "<ip:8021>"); Job job = new Job(conf, "wordcount"); job.setJarByClass(WordCountNewAPI.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(IntWritable.class); job.setMapperClass(WordCountMapper.class); job.setCombinerClass(WordCountReducer.class); job.setReducerClass(WordCountReducer.class); job.setInputFormatClass(TextInputFormat.class); job.setOutputFormatClass(TextOutputFormat.class); FileInputFormat.setInputPaths(job, new Path("<path to input dir>")); FileOutputFormat.setOutputPath(job, new Path("<path to output dir>")); FileSystem fs = FileSystem.get(new URI("hdfs://<ip>:8020"), new Configuration()); fs.mkdirs(new Path("<remote path>")); fs.copyFromLocalFile(new Path("<local path>/test.jar"), new Path("<remote path>")); DistributedCache.addArchiveToClassPath(new Path("<remote path>/test.jar"), conf, fs); boolean b = job.waitForCompletion(true); if (!b) { throw new IOException("error with job!"); } return null; } }); } } 2011/11/24 Bejoy Ks <bejoy.had...@gmail.com>: > Hi Denis > Unfortunately the mailing lists strips off attachments, So it'd be > great if you could paste the source in some location and share the url of > the same. If the source is small enough then please include the same in > subject body. > > For a quick comparison, Try comparing your code with the following sample. > I just scribbled it long back and it was working > http://kickstarthadoop.blogspot.com/2011/05/word-count-example-with-hadoop-020.html > > Hope it helps!.. > > Regards > Bejoy.K.S > > On Thu, Nov 24, 2011 at 4:20 PM, Denis Kreis <de.kr...@gmail.com> wrote: > >> Hi >> >> I' trying to modify the word count example >> (http://wiki.apache.org/hadoop/WordCount) using the new api >> (org.apache.hadoop.mapreduce.*). I run the job on a remote >> pseudo-distributed cluster. It works fine with the old api, but when I >> using the new one, i'm getting this: >> >> >> 11/11/24 11:28:02 INFO mapred.JobClient: Task Id : >> attempt_201111241046_0005_m_000000_0, Status : FAILED >> java.lang.RuntimeException: java.lang.ClassNotFoundException: >> WordCountNewAPI$WordCountMapper >> at >> org.apache.hadoop.conf.Configuration.getClass(Configuration.java:866) >> at >> org.apache.hadoop.mapreduce.JobContext.getMapperClass(JobContext.java:199) >> at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:719) >> at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370) >> at org.apache.hadoop.mapred.Child$4.run(Child.java:255) >> at java.security.AccessController.doPrivileged(Native Method) >> at javax.security.auth.Subject.doAs(Subject.java:396) >> at >> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1059) >> at org.apache.hadoop.mapred.Child.main(Child.java:249) >> Caused by: java.lang.ClassNotFoundException: >> WordCountNewAPI$WordCountMapper >> at java.net.URLClassLoader$1.run(URLClassLoader.java:202) >> at java.security.AccessController.doPrivileged(Native Method) >> at java.net.URLClassLoader.findClass(URLClassLoader.java:190) >> at java.lang.ClassLoader.loadClass(ClassLoader.java:306) >> at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) >> at java.lang.ClassLoader.loadClass(ClassLoader.java:247) >> at java.lang.Class.forName0(Native Method) >> at java.lang.Class.forName(Class.java:247) >> at >> org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:819) >> at >> org.apache.hadoop.conf.Configuration.getClass(Configuration.java:864) >> ... 8 more >> >> The sources are in the attachment >> >> Regards >> Denis >> >