poi excel 파일 읽기 (office 2003 버전 이하 읽기 또는 2007 버전 이상 지원)

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.math.BigDecimal;
import java.util.HashMap;

import org.apache.poi.hssf.usermodel.HSSFRichTextString;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.DataFormat;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class ExcelReportFile {

	private static final long serialVersionUID = 612381396391426330L;

	private Workbook workBook = null;
	private HashMap<Integer, CellStyle> numberCellStyles = null;
	private CellStyle textCellStyle = null;
	private static int DEFAULT_SHEET_INDEX = 0;


	public ExcelReportFile(File file) throws FileNotFoundException, IOException {

        try {
        	// office 2007 
        	workBook = new XSSFWorkbook(new FileInputStream(file));
        } catch (Exception ex) {
        	// office 2003 
        	workBook = new HSSFWorkbook(new FileInputStream(file));
        } 

	}

	public Object getValue(int rowIndex, int colIndex) {
		return readCellValue(rowIndex, colIndex);
	}

	/**
	 *  ， excel 
	 * 
	 * @param rowNo
	 * @param colNo
	 * @return
	 */
	public String getValueByNo(int rowNo, int colNo) {
		Object rtnValue = readCellValue(rowNo - 1, colNo - 1);
		String sValue = String.valueOf((rtnValue == null) ? "" : rtnValue);
		return sValue;
	}

	private Object readCellValue(int rowIndex, int colIndex) {

		Object sCellValue = null;
		Row row = workBook.getSheetAt(0).getRow(rowIndex);

		if (row != null) {
			Cell cell = row.getCell(colIndex);

			if (cell != null) {

				int cellType = cell.getCellType();

				// HSSFCell.CELL_TYPE_FORMULA

				// Empty
				if (cellType == Cell.CELL_TYPE_BLANK) {
					sCellValue = null;
					// int dCellValue = 0;
					// sCellValue = dCellValue;
				}

				// String
				if (cellType == Cell.CELL_TYPE_STRING) {
					sCellValue = cell.getRichStringCellValue().getString()
							.trim();
				}

				// Number
				if (cellType == Cell.CELL_TYPE_NUMERIC) {
					int dCellValue = (int) cell.getNumericCellValue();
					sCellValue = dCellValue;
				}

				// formula
				if (cellType == Cell.CELL_TYPE_FORMULA) {
					sCellValue = cell.getCellFormula();
				}

			}
		}

		return sCellValue;
	}

	public void writeNumber(int sheetIndex, int rowIndex, int colIndex,
			Number value, int scale) {

		Cell cell = getCell(sheetIndex, rowIndex, colIndex);
		// HSSFCellStyle cellStyle = getNumberCellStyle(scale);

		// cell.setCellStyle(cellStyle);
		cell.setCellValue(value.doubleValue());
	}

	public void writeText(int sheetIndex, int rowIndex, int colIndex,
			String value) {

		Cell cell = getCell(sheetIndex, rowIndex, colIndex);
		// HSSFCellStyle cellStyle = getTextCellStyle();
		// cell.setCellType(HSSFCell.CELL_TYPE_STRING);
		// cellStyle.setDataFormat(HSSFDataFormat.getBuiltinFormat("text"));
		// cell.setCellStyle(cellStyle);

		cell.setCellValue(new HSSFRichTextString(value));
	}

	public void writeText(int rowIndex, int colIndex, String value) {
		writeText(DEFAULT_SHEET_INDEX, rowIndex, colIndex, value);
	}

	public void writeTextByNo(int rowIndex, int colIndex, String value) {
		writeText(DEFAULT_SHEET_INDEX, rowIndex - 1, colIndex - 1, value);
	}

	public void writeNumber(int rowIndex, int colIndex, Number value, int scale) {
		writeNumber(DEFAULT_SHEET_INDEX, rowIndex, colIndex, value, scale);
	}

	public void writeNumberByNo(int rowIndex, int colIndex, Number value,
			int scale) {
		writeNumber(DEFAULT_SHEET_INDEX, rowIndex - 1, colIndex - 1, value,
				scale);
	}

	private Cell getCell(int sheetIndex, int rowIndex, int colIndex) {

		// Sheet
		Sheet sheet = null;
		try {
			sheet = workBook.getSheetAt(sheetIndex);
		} catch (IllegalArgumentException ex) {
			sheet = workBook.createSheet();
		}

		// Row
		Row row = null;
		row = sheet.getRow(rowIndex);
		if (row == null) {
			row = sheet.createRow(rowIndex);
		}

		// Cell
		Cell cell = null;
		cell = row.getCell(colIndex);
		if (cell == null) {
			cell = row.createCell(colIndex);
		}

		return cell;
	}

	private CellStyle getNumberCellStyle(int scale) {

		if (this.numberCellStyles == null) {
			this.numberCellStyles = new HashMap<Integer, CellStyle>();
		}

		if (this.numberCellStyles.get(Integer.valueOf(scale)) == null) {
			CellStyle numberCellStyle = workBook.createCellStyle();

			StringBuilder zeroBd = new StringBuilder();
			DataFormat format = this.workBook.createDataFormat();
			zeroBd.append("0");

			if (scale > 0) {
				zeroBd.append(".");
				for (int zCount = 0; zCount < scale; zCount++) {
					zeroBd.append("0");
				}
			}

			short doubleFormat = format.getFormat(zeroBd.toString());
			numberCellStyle.setDataFormat(doubleFormat);

			this.numberCellStyles.put(Integer.valueOf(scale), numberCellStyle);
			return numberCellStyle;
		} else {
			return this.numberCellStyles.get(Integer.valueOf(scale));
		}
	}

	public void write(OutputStream stream) throws IOException {
		if (this.workBook != null && stream != null) {
			this.workBook.write(stream);
		}
	}

	private CellStyle getTextCellStyle() {
		if (textCellStyle != null) {
			return textCellStyle;
		} else {
			return this.workBook.createCellStyle();
		}
	}

	/**
	 *  
	 * 
	 * @param colIndexStr
	 * @return
	 */
	public static int convertColIndexString2Number(String colIndexStr) {
		int len = colIndexStr.toUpperCase().length();
		char[] chars = colIndexStr.toCharArray();
		int col = 0;
		for (int index = 0; index < len; index++) {
			char ca = chars[index];
			int charAInt = Character.getNumericValue('A');
			int charInt = Character.getNumericValue(ca);

			BigDecimal bg = new BigDecimal(26);
			col = col + bg.pow(len - index - 1).intValue()
					* (charInt - charAInt + 1);
		}
		return col;
	}
	
}