I have a file with data having text and "^" in between:
SOME TEXT^GOES HERE^
AND A FEW^MORE
GOES HERE
I am writing a custom input format to delimit the rows using "^" character. i.e The output of the mapper should be like:
SOME TEXT
GOES HERE
AND A FEW
MORE GOES HERE
I have written a written a custom input format which extends FileInputFormat and also written a custom record reader that extends RecordReader. Code for my custom record reader is given below. I dont know how to proceed with this code. Having trouble with the nextKeyValue() method in the WHILE loop part. How should I read the data from a split and generate my custom key-value? I am using all new mapreduce package instead of the old mapred package.
public class MyRecordReader extends RecordReader<LongWritable, Text>
{
long start, current, end;
Text value;
LongWritable key;
LineReader reader;
FileSplit split;
Path path;
FileSystem fs;
FSDataInputStream in;
Configuration conf;
@Override
public void initialize(InputSplit inputSplit, TaskAttemptContext cont) throws IOException, InterruptedException
{
conf = cont.getConfiguration();
split = (FileSplit)inputSplit;
path = split.getPath();
fs = path.getFileSystem(conf);
in = fs.open(path);
reader = new LineReader(in, conf);
start = split.getStart();
current = start;
end = split.getLength() + start;
}
@Override
public boolean nextKeyValue() throws IOException
{
if(key==null)
key = new LongWritable();
key.set(current);
if(value==null)
value = new Text();
long readSize = 0;
while(current<end)
{
Text tmpText = new Text();
readSize = read //here how should i read data from the split, and generate key-value?
if(readSize==0)
break;
current+=readSize;
}
if(readSize==0)
{
key = null;
value = null;
return false;
}
return true;
}
@Override
public float getProgress() throws IOException
{
}
@Override
public LongWritable getCurrentKey() throws IOException
{
}
@Override
public Text getCurrentValue() throws IOException
{
}
@Override
public void close() throws IOException
{
}
}
