ExcelRecordReader.java

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package com.milind.mr.excel;

/**
*
* @author milind
*/
import java.io.IOException;
import java.io.InputStream;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.FileSplit;
/**
* Reads excel spread sheet , where keys are offset in file and value is the row
* containing all column as a string.
*/
public class ExcelRecordReader extends RecordReader<LongWritable, Text> {

private LongWritable key;
private Text value;
private InputStream is;
private String[] strArrayofLines;

@Override
public void initialize(InputSplit genericSplit, TaskAttemptContext context)
throws IOException, InterruptedException {

FileSplit split = (FileSplit) genericSplit;
Configuration job = context.getConfiguration();
final Path file = split.getPath();

FileSystem fs = file.getFileSystem(job);
FSDataInputStream fileIn = fs.open(split.getPath());

is = fileIn;
String line = new ExcelParser().parseExcelData(is);
this.strArrayofLines = line.split("\n");
}

@Override
public boolean nextKeyValue() throws IOException, InterruptedException {

if (key == null) {
key = new LongWritable(0);
value = new Text(strArrayofLines[0]);

} else {

if (key.get() < (this.strArrayofLines.length - 1)) {
long pos = (int) key.get();

key.set(pos + 1);
value.set(this.strArrayofLines[(int) (pos + 1)]);

pos++;
} else {
return false;
}

}

if (key == null || value == null) {
return false;
} else {
return true;
}

}

@Override
public LongWritable getCurrentKey() throws IOException,
InterruptedException {
  return key;
}
@Override
public Text getCurrentValue() throws IOException, InterruptedException {
  return value;
}
@Override
public float getProgress() throws IOException, InterruptedException {
  return 0;
}
@Override
public void close() throws IOException {
  if (is != null) {
    is.close();
  }
}
}

This class is used for reading every record in the excel file which is read using MapReduce API