public XLS2CSVmra(String filename,
    int minColumns) throws IOException, FileNotFoundException 
{
		this(
				new POIFSFileSystem(new FileInputStream(filename)),
				System.out, minColumns
		);
}

Creates a new XLS -> CSV converter

Parameters:

filename - The file to process

minColumns - The minimum number of columns to output, or -1 for no minimum

Throws:

IOException -

FileNotFoundException -

 public XLS2CSVmra(POIFSFileSystem fs,
    PrintStream output,
    int minColumns) 
{
	                                    	 
		this.fs = fs;
		this.output = output;
		this.minColumns = minColumns;
}

Creates a new XLS -> CSV converter

Parameters:

fs - The POIFSFileSystem to process

output - The PrintStream to output the CSV to

minColumns - The minimum number of columns to output, or -1 for no minimum

 public static  void main(String[] args) throws Exception 
{
		if(args.length <  1) {
			System.err.println("Use:");
			System.err.println("  XLS2CSVmra < xls file > [min columns]");
			System.exit(1);
		}
		int minColumns = -1;
		if(args.length  >= 2) {
			minColumns = Integer.parseInt(args[1]);
		}
		XLS2CSVmra xls2csv = new XLS2CSVmra(args[0], minColumns);
		xls2csv.process();
}

 public  void process() throws IOException 
{
		MissingRecordAwareHSSFListener listener = new MissingRecordAwareHSSFListener(this);
		formatListener = new FormatTrackingHSSFListener(listener); 
		HSSFEventFactory factory = new HSSFEventFactory();
		HSSFRequest request = new HSSFRequest();
		request.addListenerForAllRecords(formatListener);
		factory.processWorkbookEvents(request, fs);
}

Initiates the processing of the XLS file to CSV

 public  void processRecord(Record record) 
{
		int thisRow = -1;
		int thisColumn = -1;
		String thisStr = null;
		switch (record.getSid())
        {
		case SSTRecord.sid:
			sstRecord = (SSTRecord) record;
			break;
        case BlankRecord.sid:
        	BlankRecord brec = (BlankRecord) record;
            thisRow = brec.getRow();
            thisColumn = brec.getColumn();
            thisStr = "";
            break;
        case BoolErrRecord.sid:
        	BoolErrRecord berec = (BoolErrRecord) record;
            thisRow = berec.getRow();
            thisColumn = berec.getColumn();
            thisStr = "";
            break;
        case FormulaRecord.sid:
        	FormulaRecord frec = (FormulaRecord) record;
        	thisRow = frec.getRow();
        	thisColumn = frec.getColumn();
        	if(outputFormulaValues) {
        		if(Double.isNaN( frec.getValue() )) {
        			// Formula result is a string
        			// This is stored in the next record
        			outputNextStringRecord = true;
    	        	nextRow = frec.getRow();
    	        	nextColumn = frec.getColumn();
        		} else {
        			thisStr = formatNumberDateCell(frec, frec.getValue());
        		}
        	} else {
        		thisStr = '"" + 
        			FormulaParser.toFormulaString(null, frec.getParsedExpression()) + '"";
        	}
            break;
        case StringRecord.sid:
        	if(outputNextStringRecord) {
        		// String for formula
        		StringRecord srec = (StringRecord)record;
        		thisStr = srec.getString(); 
        		thisRow = nextRow;
        		thisColumn = nextColumn;
        		outputNextStringRecord = false;
        	}
            break;
        case LabelRecord.sid:
        	LabelRecord lrec = (LabelRecord) record;
            thisRow = lrec.getRow();
            thisColumn = lrec.getColumn();
            thisStr = '"" + lrec.getValue() + '"";
            break;
        case LabelSSTRecord.sid:
        	LabelSSTRecord lsrec = (LabelSSTRecord) record;
            thisRow = lsrec.getRow();
            thisColumn = lsrec.getColumn();
            if(sstRecord == null) {
            	thisStr = '"" + "(No SST Record, can't identify string)" + '"";
            } else {
            	thisStr = '"" + sstRecord.getString(lsrec.getSSTIndex()).toString() + '"";
            }
            break;
        case NoteRecord.sid:
        	NoteRecord nrec = (NoteRecord) record;
        	thisRow = nrec.getRow();
        	thisColumn = nrec.getColumn();
        	// TODO: Find object to match nrec.getShapeId()
        	thisStr = '"" + "(TODO)" + '"";
            break;
        case NumberRecord.sid:
            NumberRecord numrec = (NumberRecord) record;
            thisRow = numrec.getRow();
            thisColumn = numrec.getColumn();
            // Format
            thisStr = formatNumberDateCell(numrec, numrec.getValue());
            break;
        case RKRecord.sid:
        	RKRecord rkrec = (RKRecord) record;
        	thisRow = rkrec.getRow();
        	thisColumn = rkrec.getColumn();
        	thisStr = '"" + "(TODO)" + '"";
        	break;
        default:
        	break;
        }
		// Handle new row
		if(thisRow != -1 && thisRow != lastRowNumber) {
			lastColumnNumber = -1;
		}
		// Handle missing column
		if(record instanceof MissingCellDummyRecord) {
			MissingCellDummyRecord mc = (MissingCellDummyRecord)record;
			thisRow = mc.getRow();
			thisColumn = mc.getColumn();
			thisStr = "";
		}
		// If we got something to print out, do so
		if(thisStr != null) {
			if(thisColumn  > 0) {
				output.print(',");
			}
			output.print(thisStr);
		}
		// Update column and row count
		if(thisRow  > -1)
			lastRowNumber = thisRow;
		if(thisColumn  > -1)
			lastColumnNumber = thisColumn;
		// Handle end of row
		if(record instanceof LastCellOfRowDummyRecord) {
			// Print out any missing commas if needed
			if(minColumns  > 0) {
				// Columns are 0 based
				if(lastColumnNumber == -1) { lastColumnNumber = 0; }
				for(int i=lastColumnNumber; i< (minColumns); i++) {
					output.print(',");
				}
			}
			// We're onto a new row
			lastColumnNumber = -1;
			// End the row
			output.println();
		}
}

Main HSSFListener method, processes events, and outputs the CSV as the file is processed.