Bejoy KS created MAPREDUCE-4507: ----------------------------------- Summary: IdentityMapper being triggered when the InputType at class level ane method level has a conflict Key: MAPREDUCE-4507 URL: https://issues.apache.org/jira/browse/MAPREDUCE-4507 Project: Hadoop Map/Reduce Issue Type: Bug Components: mrv1 Affects Versions: 1.0.3 Environment: linux ubuntu Reporter: Bejoy KS
If we use the default InputFormat (TextInputFormat) but specify the Key type in mapper as IntWritable instead of Long Writable. The framework is supposed throw a class cast exception.Such an exception is thrown only if the key types at class level and method level are the same (IntWritable). But if we provide the Input key type as IntWritable on the class level but LongWritable on the method level (map method), instead of throwing a compile time error, the code compliles fine . In addition to it on execution the framework triggers Identity Mapper instead of the custom mapper provided with the configuration. In this case the 'mapreduce.map.class' in job.xml shows mapper as Custom Mapper itself , it should show IdentityMapper in cases where IdentityMapper is triggered to avoid confusion and easy debugging. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira