Hi John, You can extend FileInputFormat(or implement InputFormat) and then you need to implement below methods.
1. InputSplit[] getSplits(JobConf job, int numSplits) : For splitting the input files logically for the job. If FileInputFormat.getSplits(JobConf job, int numSplits) suits for your requirement, you can make use of it. Otherwise you can implement it based on your need. 2. RecordReader<K,V> RecordReader(InputSplit split, JobConf job, Reporter reporter) : For reading the input split. Thanks Devaraj ________________________________________ From: John Hancock [jhancock1...@gmail.com] Sent: Thursday, May 17, 2012 3:40 PM To: common-user@hadoop.apache.org Subject: custom FileInputFormat class All, Can anyone on the list point me in the right direction as to how to write my own FileInputFormat class? Perhaps this is not even the way I should go, but my goal is to write a MapReduce job that gets its input from a binary file of integers and longs. -John