XssfRecordStream.java

package nl.helixsoft.misc.impl;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import nl.helixsoft.recordstream.AbstractRecordStream;
import nl.helixsoft.recordstream.DefaultRecord;
import nl.helixsoft.recordstream.DefaultRecordMetaData;
import nl.helixsoft.recordstream.Record;
import nl.helixsoft.recordstream.RecordMetaData;
import nl.helixsoft.recordstream.StreamException;

public class XssfRecordStream extends AbstractRecordStream 
{

	private final XSSFSheet sheet;
	private final RecordMetaData rmd;
	
	int rowIndex = 1;

	public XssfRecordStream (File xlsFile, String sheetTitle) throws IOException
	{
		
		XSSFWorkbook wb = new XSSFWorkbook(new FileInputStream (xlsFile));
		sheet = wb.getSheet(sheetTitle);

		XSSFRow headerRow = sheet.getRow(0);
		
		String[] header = new String[headerRow.getLastCellNum()];
		
		for (int col = 0; col < headerRow.getLastCellNum(); ++col)
		{
			XSSFCell cell = headerRow.getCell(col);
			header[col] = cell.getStringCellValue();
		}
		
		rmd = new DefaultRecordMetaData(header);
	}

	@Override
	public RecordMetaData getMetaData() 
	{
		return rmd;
	}

	@Override
	public Record getNext() throws StreamException 
	{
		if (rowIndex >= sheet.getLastRowNum()) return null;
		
		XSSFRow row = sheet.getRow(rowIndex++);
		
		if (row == null) return null; // empty row. block has ended.
		
		Object[] fields = new Object[rmd.getNumCols()];
		
		int fieldNum = Math.min (rmd.getNumCols(), row.getLastCellNum());
		
		if (rmd.getNumCols() != row.getLastCellNum())
		{
			System.out.println ("Warning: number of cells " + row.getLastCellNum() + 
					" is different from number of headers " + rmd.getNumCols() + " in row " + rowIndex);
		}
		
		for (int col = 0; col < fieldNum; ++col)
		{
			XSSFCell cell = row.getCell(col);
			if (cell == null) continue;
			int cellType = cell.getCellType();
			if (cellType == XSSFCell.CELL_TYPE_FORMULA) cellType = cell.getCachedFormulaResultType();

			switch (cellType)
			{
			case XSSFCell.CELL_TYPE_NUMERIC:
				fields[col] = cell.getNumericCellValue();
				break;
			case XSSFCell.CELL_TYPE_BOOLEAN:
				fields[col] = cell.getBooleanCellValue();
				break;
			case XSSFCell.CELL_TYPE_BLANK:
				fields[col] = null;
				break;
			case XSSFCell.CELL_TYPE_STRING:
				fields[col] = cell.getStringCellValue();
				break;
			case XSSFCell.CELL_TYPE_ERROR:
				fields[col] = cell.getErrorCellValue();
				break;
			default:
				throw new IllegalStateException ("Unknown type " + cellType);
			}
		}
		
		return new DefaultRecord (rmd, fields);
	}

	@Override
	public void close() { }

}