Excel 文件下载和导出的方法封装

/**
	 * 
	 *@注释 导出Excel
	 *@方法名称 genericSheet
	 * @param title 标题
	 * @param headList 表头列（KeyValueBean key是字段名称  value是说明文字）
	 * @param data 导出数据
	 * @param work 可添加新增的sheet
	 * @return
	 */
	public static HSSFWorkbook genericSheet(String title,List<KeyValueBean> headList, List<Map<String,Object>> data, HSSFWorkbook work) {
		if(work == null) work = new HSSFWorkbook();
		 HSSFCellStyle dataStyle = work.createCellStyle();
		 dataStyle.setWrapText(true);
	    // 字体对象设置  
 		 HSSFFont font = work.createFont();
 		 font.setFontHeightInPoints((short) 16);
 		 font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);  
 		 // 表头字体颜色
	     HSSFFont colorFont = work.createFont();  
	     colorFont.setColor(HSSFColor.RED.index); 		
 		 // 大标题格式  
 	     HSSFCellStyle titleStyle = work.createCellStyle();  
 	     titleStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
 	     titleStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
 	     titleStyle.setFont(font);
 	     // 数据表头格式    并设置值表头 设置表头居中
 	     HSSFCellStyle style = work.createCellStyle();  
 	     style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
 	     style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
 	     style.setFillForegroundColor(HSSFColor.GREY_25_PERCENT.index);// 设置背景色
 	     style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
 	     // 设置边框
 	     style.setBorderBottom(HSSFCellStyle.BORDER_THIN); //下边框
 	     style.setBorderLeft(HSSFCellStyle.BORDER_THIN);//左边框
 	     style.setBorderTop(HSSFCellStyle.BORDER_THIN);//上边框
 	     style.setBorderRight(HSSFCellStyle.BORDER_THIN);//右边框
 	     // 说明格式
	     HSSFCellStyle explainStyle = work.createCellStyle();//说明格式加红标注
	     explainStyle.setWrapText(true);//设置自动换行
	     explainStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN); //下边框
	     explainStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);//左边框
	     explainStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);//上边框
	     explainStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);//右边框
	     explainStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_TOP);
	     explainStyle.setFont(colorFont);
	     HSSFCellStyle wrapStyle = work.createCellStyle(); // 说明格式标注
	     wrapStyle.setWrapText(true);
	     wrapStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_TOP);
	     wrapStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN); //下边框
	     wrapStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);//左边框
	     wrapStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);//上边框
	     wrapStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);//右边框
	     wrapStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_TOP);
	     
	     // 创建sheet
	     HSSFSheet sheet = work.createSheet(title);
	     sheet.setDefaultColumnWidth(20); // 默认列宽
		 sheet.setDefaultRowHeightInPoints(20);
		 int rows = 2;// 行号
    	 HSSFRow headerRow = sheet.createRow((int) 0);
	     Region region = new Region(0, (short) 0, 1, (short) (headList.size()-1)); //参数1：行号   参数2：起始列号   参数3：行号     参数4：终止列号O
	     sheet.addMergedRegion(region);
	     HSSFCell cellTitle = headerRow.createCell((short) 0); 
	     cellTitle.setCellValue(title);
	     cellTitle.setCellStyle(titleStyle);
 	    
	     HSSFRow explRow1 = null;// 说明表头1
	     HSSFRow explRow2 = null;// 说明表头2
	     HSSFCell explCell1 = null;//说明1表头单元格
	     HSSFCell explCell2 = null;//说明2表头单元格
	     if(StringUtils.isNotBlank(headList.get(0).getValue())) {
	    	 explRow1 = sheet.createRow(rows);
		     explRow2 = sheet.createRow(rows + 1);
	    	 rows = rows + 2;
	     }
	     HSSFRow row = sheet.createRow(rows);//表头
	     HSSFCell cell = row.createCell((short) 0);//表头单元格
	     for (int k = 0; k < headList.size(); k++) {//循环迭代表头并设置说明及列名称
		   String colName = headList.get(k).getKey();
		   if(explRow1 != null && explRow2 != null) {// 存在说明表头设置列说明
			   explCell1 = explRow1.createCell((short) (k));//创建表头说明1单元格
			   explCell2 = explRow2.createCell((short) (k));//创建表头说明2单元格
			   explCell1.setCellValue(headList.get(k).getValue());
			   if(colName.indexOf("!") != -1){
				   explCell1.setCellStyle(explainStyle);
				   explCell2.setCellStyle(explainStyle);
			   } else {
				   explCell1.setCellStyle(wrapStyle);
				   explCell2.setCellStyle(wrapStyle);
			   }
			   Region explainRegion = new Region(2, (short) k, 3, (short) k); //参数1：行号   参数2：起始列号   参数3：行号     参数4：终止列号O
			   sheet.addMergedRegion(explainRegion);
		   }
		   cell = row.createCell((short) (k));// 设置列名称
		   cell.setCellValue(colName.replaceAll("!", ""));
		   cell.setCellStyle(style);
	   }
	   row = sheet.createRow(rows + 1); // 生成数据
	   if(!CollectionUtil.isEmpty(data)) {
		   for(int j = 0; j < data.size(); j++) {
				Map<String,Object> obj = data.get(j);
				row = sheet.createRow(rows + j + 1);
				for(int i = 0; i < headList.size(); i++) {
					HSSFCell createCell = row.createCell(i);
					createCell.setCellStyle(dataStyle);
					createCell.setCellValue(obj.get(headList.get(i).getKey()) != null?obj.get(headList.get(i).getKey()).toString():Constant.EMPTY_STRING); 
				}
			}
	   }
	   return work;
	}