public class ExportExcelUtil {

 /**
  * 這是一個通用的方法，利用了JAVA的反射機制，可以將放置在JAVA集合中并且符號一定條件的數據以EXCEL 的形式輸出到指定IO設備上
  *
  * @param title
  *            表格標題名
  * @param headers
  *            表格屬性列名數組
  * @param dataset
    *     需要顯示的數據集合,集合中一定要放置符合javabean風格的類的對象。此方法支持的
     *            javabean屬性的數據類型有基本數據類型及String,Date,byte[](圖片數據)
     * @param fieldNames
     *            傳入的對應headers屬性列名數組的具體的字段名稱,javabean風格,模式如：model.user.name
  * @param out
  *            與輸出設備關聯的流對象，可以將EXCEL文檔導出到本地文件或者網絡中
  * @param pattern 
  *            如果有時間數據，設定輸出格式。默認為"yyy-MM-dd"
  */

 public void exportExcel(String title, String[] headers,String[] fieldNames,List dataset, OutputStream out, String pattern) {
  headers=this.addString("序號", 0, headers);
  int column=headers.length;
  
  HSSFWorkbook hwb = POIExcelUtil.createWorkbook();// 創建一個excel工作單
  HSSFSheet hs=hwb.createSheet(title);
  
  HSSFPatriarch patriarch = hs.createDrawingPatriarch();
  // 定義注釋的大小和位置,詳見文檔
  HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0,0, 0, 0, (short) 4, 2, (short) 6, 5));
  comment.setString(new HSSFRichTextString("提示:數據為單頁數據！"));
  comment.setAuthor("liuhonglai");
  
  hs.addMergedRegion(new CellRangeAddress(0, (short) 0, 0,(short) (column - 1))); // 合并單元格
  int listSize = dataset!=null?dataset.size():0;
  int rows = listSize + 2;// 定義總的行數
  
  for (int i = 0; i < rows; i++) {// 循環創建行數
   HSSFRow hr = POIExcelUtil.createRow(i, hs);// 根據查詢的數據在sheet中創建行
   for (int j = 0; j < column; j++) {// 循環列數
    HSSFCell hc = POIExcelUtil.createCell(j, hr);// 創建列
    if (i == 0) {// 控制第一行的樣式
     HSSFCellStyle cs = POIExcelUtil.createCellStyle(hwb);
     HSSFFont font = POIExcelUtil.createFont(hwb);
     font.setFontHeightInPoints((short) 14);
     font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
     cs.setFont(font);// 設置字體
     cs.setWrapText(true);
     cs.setBorderBottom(HSSFCellStyle.BORDER_THIN);// 下邊框
     cs.setBorderLeft(HSSFCellStyle.BORDER_NONE);// 左邊框
     cs.setBorderRight(HSSFCellStyle.BORDER_NONE);// 右邊框
     cs.setBorderTop(HSSFCellStyle.BORDER_NONE);// 上邊框
     cs.setAlignment(CellStyle.ALIGN_CENTER);// 設置水平對齊方式
     cs.setVerticalAlignment(CellStyle.VERTICAL_CENTER);// 設置垂直對齊方式
     StringBuffer buffer = new StringBuffer();
     buffer.append(title);
     POIExcelUtil.setSheetTitle(hs, cs, hr, hc, buffer.toString()); // 設置標題
     break;
    }
    if (i == 1) {// 控制第二行的樣式,并設置列的名稱
     HSSFCellStyle cs = POIExcelUtil.createCellStyle(hwb);
     hr.setHeightInPoints((float) 24);
     HSSFFont font = POIExcelUtil.createFont(hwb);
     cs.setFont(font);// 設置字體
     cs.setAlignment(CellStyle.ALIGN_CENTER);
     cs.setVerticalAlignment(CellStyle.VERTICAL_CENTER);
     cs.setFillForegroundColor(HSSFColor.GREY_25_PERCENT.index);// 設置單元格背景
     cs.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
     hc.setCellType(HSSFCell.CELL_TYPE_STRING);
     hc.setCellStyle(cs);
     hc.setCellValue(headers[j]);
    } else {// 設置內容
     if(dataset!=null){
      switch (j) {
      case 0: //序號
       hc.setCellValue(i - 1);
       break;
      default:
       Object t= dataset.get(i - 2);// 去掉前兩行
          if(j==2||j==3){
           hs.setColumnWidth((int) j, (int) (35.7 * 150));
          }else{
           hs.setColumnWidth((int) j, (int) (35.7 * 80)); 
          }
       String fieldName =fieldNames[j-1];
      
       Object value=null;
//       String getMethodName = "get"+ fieldName.substring(0, 1).toUpperCase()+ fieldName.substring(1);
//       Class tCls = t.getClass();
//        try {
//         Method getMethod = tCls.getMethod(getMethodName,new Class[] {});
//         value = getMethod.invoke(t, new Object[] {});
//        } catch (SecurityException e) {
//         // TODO Auto-generated catch block
//         e.printStackTrace();
//        } catch (IllegalArgumentException e) {
//         // TODO Auto-generated catch block
//         e.printStackTrace();
//        } catch (NoSuchMethodException e) {
//         // TODO Auto-generated catch block
//         e.printStackTrace();
//        } catch (IllegalAccessException e) {
//         // TODO Auto-generated catch block
//         e.printStackTrace();
//        } catch (InvocationTargetException e) {
//         // TODO Auto-generated catch block
//         e.printStackTrace();
//        }
       
       value = getColumnValue(t, fieldName);
       String textValue = null;
        if (value instanceof Integer) {
           int intValue =( (Integer) value).intValue();
           textValue=String.valueOf(intValue);
        } else if (value instanceof Float) {
           float fValue = ((Float) value).floatValue();
           textValue=String.valueOf(fValue);
        } else if (value instanceof Double) {
         double dValue =( (Double) value).doubleValue();
         textValue=String.valueOf(dValue);
        } else if (value instanceof Long) {
         long longValue =( (Long) value).longValue();
         textValue=String.valueOf(longValue);
        }else if (value instanceof Boolean) {
        boolean bValue = ((Boolean) value).booleanValue();
        textValue=String.valueOf(bValue);
       } else if (value instanceof Date) {
        Date date = (Date) value;
        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
        textValue = sdf.format(date);
       } else if (value instanceof byte[]) {
        // 有圖片時，設置行高為60px;
        hr.setHeightInPoints(60);
        // 設置圖片所在列寬度為80px,注意這里單位的一個換算
        hs.setColumnWidth(i, (short) (35.7 * 80));
        // sheet.autoSizeColumn(i);
        byte[] bsValue = (byte[]) value;
        HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0,
          1023, 255, (short) 6, i-1, (short) 6, i-1);
        anchor.setAnchorType(2);
        patriarch.createPicture(anchor, hwb.addPicture(
          bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
       } else {
        // 其它數據類型都當作字符串簡單處理
        if(value==null){
         textValue="";
        }else{
         textValue = value.toString();
        }
       }
        hc.setCellValue(textValue);
       break;
      }
     }
    }
   }
  }
  POIExcelUtil.setPrintSetup(hwb, hs, rows, column);
  try {
   hwb.write(out);
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }
 
 /**
  * 遞歸方式處理.
  * @param obj 傳入的對象
  * @param fileNames 有層級javabean方式,model.user.name
  * @return Object 值
  * @author david
  */
 private static Object getColumnValue(Object obj,String fieldNames){
  if(null != fieldNames && !"".equals(fieldNames)){
   try {
    Object objVal = null;
    int sp = fieldNames.indexOf(".");
    String fieldName = "";
    String afterFieldNames = "";
    
    if(sp == -1){
     fieldName = fieldNames;
    }else{
     fieldName = fieldNames.substring(0,sp);
     afterFieldNames = fieldNames.substring(sp + 1,fieldNames.length());
    }
    
    String getMethodName = "get"+ fieldName.substring(0, 1).toUpperCase()+ fieldName.substring(1);
    Class classz = obj.getClass();
    Method getMethod;
    getMethod = classz.getMethod(getMethodName,new Class[] {});
    objVal = getMethod.invoke(obj, new Object[] {});
    
    if(StringUtils.isBlank(afterFieldNames)){
     return objVal;
    }else{
     return getColumnValue(objVal, afterFieldNames);
    }
   } catch (SecurityException e) {
    e.printStackTrace();
   } catch (NoSuchMethodException e) {
    e.printStackTrace();
   } catch (IllegalArgumentException e) {
    e.printStackTrace();
   } catch (IllegalAccessException e) {
    e.printStackTrace();
   } catch (InvocationTargetException e) {
    e.printStackTrace();
   }
  }
  return null;
 }
 
  private  String[] addString(String str,int index,String[] old){
     String[] temp=new String[old.length+1];
     System.arraycopy(old, 0, temp, 0, old.length);
     for(int i=old.length;i>index;i--){
      temp[i]=temp[i-1];
     }
     temp[index]=str;
     return temp;
  }
}