RSJcompositeKey ckwKey = new RSJcompositeKey();

Text txtValue = new Text("");

int intSrcIndex = 0;

StringBuilder strMapValueBuilder = new StringBuilder("");

List<Integer> lstRequiredAttribList = new ArrayList<Integer>();

@Override

protected void setup(Context context) throws IOException,InterruptedException {

// Get the source index; (employee = 1, salary = 2)

// Added as configuration in driver

FileSplit fsFileSplit = (FileSplit) context.getInputSplit();

intSrcIndex = Integer.parseInt(context.getConfiguration().get(fsFileSplit.getPath().getName()));

// Initialize the list of fields to emit as output based on

// intSrcIndex (1=employee, 2=current salary, 3=historical salary)

if (intSrcIndex == 1) // employee

{

lstRequiredAttribList.add(1); // FName

lstRequiredAttribList.add(2); // LName

lstRequiredAttribList.add(3); // Gender

}

else // salary

{

lstRequiredAttribList.add(1); // Salary

lstRequiredAttribList.add(3); // Effective-to-date (Value of

// 9999-01-01 indicates current

// salary)

}

}

private String buildMapValue(String arrEntityAttributesList[]) {

// This method returns csv list of values to emit based on data entity

strMapValueBuilder.setLength(0);// Initialize

// Build list of attributes to output based on source - employee/salary

for (int i = 1; i < arrEntityAttributesList.length; i++)

{

// If the field is in the list of required output

// append to stringbuilder

if (lstRequiredAttribList.contains(i))

{

strMapValueBuilder.append(arrEntityAttributesList[i]).append(",");

}

}

if (strMapValueBuilder.length() > 0)

{

// Drop last comma

strMapValueBuilder.setLength(strMapValueBuilder.length() - 1);

}

return strMapValueBuilder.toString();

}

@Override

public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {

if (value.toString().length() > 0)

{

String arrEntityAttributes[] = value.toString().split("\t");

ckwKey.setJoinKey(arrEntityAttributes[0].toString());

ckwKey.setSourceIndex(intSrcIndex);

txtValue.set(buildMapValue(arrEntityAttributes));

context.write(ckwKey, txtValue);

}

}