java导出Excel例子（poi）

public class creatFile {
    static public void main(String[] args) throws Exception {

        FileOutputStream fos = new FileOutputStream("d:\\creatFile.xls"); 
        HSSFWorkbook wb = new HSSFWorkbook(); 
        HSSFSheet s = wb.createSheet(); 
        wb.setSheetName(0, "first sheet"); 
        HSSFRow row = s.createRow(0);
        HSSFCell cell = row.createCell((short)0);
        cell.setCellValue("Hello! This message is generated from POI."); 
        wb.write(fos); 
        fos.close(); 
    }
} 
 
public class AppendFile {

    public static void main(String[] args) throws FileNotFoundException, IOException
    {        
        POIFSFileSystem fs =new POIFSFileSystem(new FileInputStream("d:\\test.xls"));    
      
        //  创建一个新的Excel
        HSSFWorkbook wb = new HSSFWorkbook(fs);
        
        //  在所创建的Excel中新建一个sheet页
        HSSFSheet sheet = wb.getSheetAt(0);
        
        //  取该sheet页的第13行
        HSSFRow row = sheet.getRow(12);
        
        //  第8列的单元格
        HSSFCell cell = row.getCell((short)7);

        System.out.println(cell);
        String    src    = "单元格";
        
        //  在所取得单元格中书写内容
        cell.setEncoding(HSSFCell.ENCODING_UTF_16);
        cell.setCellValue(src);
        
      
        // Write the output to a file
        FileOutputStream fileOut = new FileOutputStream("d:\\ww.xls");
        
        wb.write(fileOut);
        
        fileOut.close();
    }
}