Hi, here i am trying to read rows from a table, and put them to a file as
it is.For that my mapper class and run method are as shown below. (Correct
me if any thing wrong).
public static class SIMapper extends
TableMapper<ImmutableBytesWritable,Text> {
Configuration config=HBaseConfiguration.create();
private Text TABLE=new Text("HS3");
public void map(ImmutableBytesWritable row, Text value, Context
context) throws IOException {
try {
context.write(row, TABLE);
} catch (InterruptedException e) {
throw new IOException(e);
}
}
}
Run method:---
public int run(String[] args) throws Exception {
Job job = new Job(getConf());
job.setJobName("Job-1");
job.setJarByClass(setjar.class);
Scan s=new Scan();
s.setCacheBlocks(false);
s.setCaching(1000);
TableMapReduceUtil.initTableMapperJob(args[0],s, SIMapper.class,
null,null, job); // args[0] is the table name, which is the input table
for mapper.
TableMapReduceUtil.addDependencyJars(job);
FileOutputFormat.setOutputPath(job, new Path(args[1]));
return job.waitForCompletion(true)? 0:1 ;
}
When i try to execute the job, i am getting following error. I don't know
what is the mistake.For what the LongWritable it is expected?
12/01/28 11:57:23 INFO mapred.JobClient: map 0% reduce 0%
12/01/28 11:57:34 INFO mapred.JobClient: Task Id :
attempt_201201281010_0004_m_000000_0, Status : FAILED
java.io.IOException: Type mismatch in key from map: expected
org.apache.hadoop.io.LongWritable, recieved
org.apache.hadoop.hbase.io.ImmutableBytesWritable
at
org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(MapTask.java:845)
at
org.apache.hadoop.mapred.MapTask$NewOutputCollector.write(MapTask.java:541)
at
org.apache.hadoop.mapreduce.TaskInputOutputContext.write(TaskInputOutputContext.java:80)
at org.apache.hadoop.mapreduce.Mapper.map(Mapper.java:124)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:621)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:305)
at org.apache.hadoop.mapred.Child.main(Child.java:170)
please some body help..
--
*Regards*
*
Vamshi Krishna
*
