expected org apache hadoop io IntWritable received org apache hadoop io LongWritable

0 votes

Hello. I am facing issue while running MapReduce program. The name of the MapReduce is WordCount which I found in a blog online. When I try to run the program. I am getting the following error:

expected org.apache.hadoop.io.IntWritable, received org.apache.hadoop.io.LongWritable
Jan 25, 2019 in Big Data Hadoop by George
 • 959 views
Could you please share the code you are using?
commented Jan 25, 2019 by Omkar
 • 69,210 points

1 answer to this question.

0 votes

Hey George! 

This error comes whenever you use any other serializable datatype for mapper key other than LongWritable. This happens only when using multiple mappers. Please have a look below for your reference.

image

image

image

With the right datatypes, it should work fine. Make the changes shown in the screenshots above and execute the program.

answered Jan 25, 2019 by Omkar
 • 69,210 points

Related Questions In Big Data Hadoop

0 votes
1 answer

ERROR org.apache.hadoop.hdfs.server.namenode.FSNamesystem: FSNamesystem initialization failed. java.io.FileNotFoundException: /app/hadoop/tmp/dfs/name/in_use.lock

Hi, You can change the owner to Hadoop ...READ MORE

answered Aug 5, 2019 in Big Data Hadoop by Gitika
 • 65,910 points • 1,497 views
0 votes
1 answer

Hadoop: Error: Exception in thread "main" java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected

Hey, The error seems you have not add ...READ MORE

answered Aug 7, 2019 in Big Data Hadoop by Gitika
 • 65,910 points • 1,618 views
0 votes
1 answer

org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /try.txt._COPYING_ could only be replicated to 0 nodes instead of minReplication (=1).

Hi@akhtar, This error may occur if your datanode ...READ MORE

answered Apr 7, 2020 in Big Data Hadoop by MD
 • 95,440 points • 7,197 views
0 votes
1 answer

Hadoop Pig: java.lang.NoClassDefFoundError: org/apache/hadoop/hbase/filter/Filter

This seems like a problem with the ...READ MORE

answered Nov 16, 2018 in Big Data Hadoop by Omkar
 • 69,210 points • 1,849 views
+1 vote
1 answer

Hadoop Mapreduce word count Program

Firstly you need to understand the concept ...READ MORE

answered Mar 16, 2018 in Data Analytics by nitinrawat895
 • 11,380 points • 10,600 views
0 votes
1 answer

hadoop.mapred vs hadoop.mapreduce?

org.apache.hadoop.mapred is the Old API  org.apache.hadoop.mapreduce is the ...READ MORE

answered Mar 16, 2018 in Data Analytics by nitinrawat895
 • 11,380 points • 2,207 views
+2 votes
11 answers

hadoop fs -put command?

Hi, You can create one directory in HDFS ...READ MORE

answered Mar 16, 2018 in Big Data Hadoop by nitinrawat895
 • 11,380 points • 104,755 views
–1 vote
1 answer

Hadoop dfs -ls command?

In your case there is no difference ...READ MORE

answered Mar 16, 2018 in Big Data Hadoop by kurt_cobain
 • 9,390 points • 4,285 views
+2 votes
1 answer

Hadoop: Type mismatch in key from map: expected org.apache.hadoop.io.Text, recieved org.apache.hadoop.io.LongWritable

Add these 2 lines in your code ...READ MORE

answered Nov 15, 2018 in Big Data Hadoop by Omkar
 • 69,210 points • 5,973 views
0 votes
1 answer

PIG - Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected

Yes, it is a compatibility issue. in Hadoop ...READ MORE

answered Oct 10, 2018 in Big Data Hadoop by Omkar
 • 69,210 points • 923 views
webinar REGISTER FOR FREE WEBINAR X
REGISTER NOW
webinar_success Thank you for registering Join Edureka Meetup community for 100+ Free Webinars each month JOIN MEETUP GROUP
"PMP®","PMI®", "PMI-ACP®" and "PMBOK®" are registered marks of the Project Management Institute, Inc. MongoDB®, Mongo and the leaf logo are the registered trademarks of MongoDB, Inc.