How to read hadoop sequential file?

Question

I have a sequential file which is the output of hadoop map-reduce job. In this file data is written in key value pairs ,and value itself is a map. I want to read the value a

Answer 1

Check the API documentation for SequenceFile#next(Writable, Writable)

while(reader.next(key,value))
{
       System.out.println("Key is: "+textKey +" value is: "+val+"\n");
}

should be replaced with

while(reader.next(key,value))
{
       System.out.println("Key is: "+key +" value is: "+value+"\n");
}

Use SequenceFile.Reader#getValueClassName to get the value type in the SequenceFile. SequenceFile have the key/value types in the file header.