java反射技術應用--靈活匯出excel
阿新 • • 發佈：2018-11-30
業務需求如下：
根據開始和結束時間查詢，時間段內的工資明細，並匯出Excel表格(根據選中的欄位匯出該列資料)
Excel共3列資料
| 年 | 月 | 具體工資明細項 如：績效，崗位補貼等
| year | month | value
實體類如下
public class Salary implements Serializable{ /** * */ private static final long serialVersionUID = 1L; private String deptCode=""; private String deptName="" private String pay=""; . . .此處省略多個欄位 public String getDeptCode() { return deptCode; } public void setDeptCode(String deptCode) { this.deptCode = deptCode; }; public String getDeptName() { return deptName; } public void setDeptName(String deptName) { this.deptName = deptName; } public String getPay() { return pay; } public void setPay(String pay) { this.pay = pay; } }
@Controller @RequestMapping("/salary") public class SalaryController { /** * * @param session * @param startDate 起始時間 * @param endDate 結束時間 * @param model * @param type 匯出工資明細型別 * @return */ @RequestMapping(value = "/exportDataWithType", method = RequestMethod.GET) public ModelAndView exportDataWithType(HttpSession session, @RequestParam(required=false) Date startDate,@RequestParam(required=false) Date endDate, ModelMap model,@RequestParam(required=false)String type) { BaseUsers user = (BaseUsers)session.getAttribute(WebConstants.CURRENT_USER); //設定查詢條件 Criteria criteria = new Criteria(); if(StringUtils.isNotBlank(user.getUserCode())){ criteria.put("staffCode", user.getUserCode()); } if(startDate != null){ criteria.put("startDate", startDate); } if(endDate != null){ criteria.put("endDate", endDate); } //經過篩選後的資料 List<Salary> newList = new ArrayList<Salary>(); try { //查詢所有資料 List<Salary> list = salaryService.queryListGerenForPage(criteria); for(Salary li:list){ Salary salary = new Salary(); salary.setYear(li.getYear()); salary.setMonth(li.getMonth()); //根據選擇的明細 對第三列的值進行設定 setTing方法 setThing(salary,type,getGetMethod(li,type)); newList.add(salary); } } catch (Exception e) { e.printStackTrace(); } ViewExcel2 viewExcel = new ViewExcel2(); model.put("data", newList); return new ModelAndView(viewExcel, model); } /** * 根據屬性名獲取get方法，並獲取對應值 * @param obj 實體類 * @param filed 屬性名 * @return 返回該屬性對應的值 */ public static Object getGetMethod(Object obj, String filed) { Object o = null; try { Class clazz = obj.getClass(); PropertyDescriptor pd = new PropertyDescriptor(filed, clazz); Method getMethod = pd.getReadMethod();//獲得get方法 if (pd != null) { o = getMethod.invoke(obj);//執行get方法返回一個Object } }catch(Exception e) { e.printStackTrace(); } return o; } /** * 獲取對應set方法 並將值賦進去 * @param obj 實體類 * @param type 傳入工資明細型別 pay * @param s 需要設定的引數值 "1000.0" */ public static void setThing(Object obj,String type,Object s){ Field field = null; try { field = obj.getClass().getDeclaredField(type); } catch (NoSuchFieldException e) { e.printStackTrace(); } catch (SecurityException e) { e.printStackTrace(); } field.setAccessible(true); try { field.set((Object) obj, s); } catch (IllegalArgumentException e1) { e1.printStackTrace(); } catch (IllegalAccessException e1) { e1.printStackTrace(); } } //內部類 生成Excel表格 class ViewExcel2 extends AbstractExcelView { @Override protected void buildExcelDocument(Map<String, Object> model, HSSFWorkbook workbook, HttpServletRequest request, HttpServletResponse response) throws Exception { response.setContentType("application/vnd.ms-excel"); response.setHeader("Content-disposition", "attachment;filename="+ new String("個人工資表.xls".getBytes(), "iso8859-1")); List<Salary> data = (List<Salary>) model.get("data"); int rowNum = 1; HSSFRow row = null; HSSFSheet sheet = workbook.createSheet("新生列表"); // 設定樣式 HSSFFont cnFont = workbook.createFont(); cnFont.setFontHeightInPoints((short) 10); cnFont.setFontName("宋體"); HSSFCellStyle cnStyle = workbook.createCellStyle(); cnStyle.setFont(cnFont); String password = null; // 設定首行資訊 HSSFRow headerRow = sheet.createRow(0); this.setExcelHeader(headerRow, data); if (data != null) { for (Salary s : data) { row = sheet.createRow(rowNum++); //設定年份 createNewCell(row, cnStyle, 0, s.getYear()); //設定月份 createNewCell(row, cnStyle, 1, s.getMonth()); Field[] fields = s.getClass().getDeclaredFields(); String[] name = new String[fields.length]; //獲取實體類 所有private 屬性 Object[] value = new Object[fields.length]; try{ Field.setAccessible(fields, true); for (int i = 0;i < name.length; i++) { //屬性名 name[i] = fields[i].getName(); //屬性值 value[i] = fields[i].get(s); if(fields[i].get(s)!=null && fields[i].get(s)!=""){ //本業務邏輯 if(!(name[i].equals("year")) && !(name[i].equals("month")) &&! (name[i].equals("serialVersionUID")) ){ //往 Excel 中第三列賦值 | year | month |fields[i].get(s).toString() 共三列 createNewCell(row, cnStyle, 2,fields[i].get(s).toString()); } } } } catch(Exception e){ e.printStackTrace(); } } } // 設定首行資訊 OutputStream ouputStream = response.getOutputStream(); workbook.write(ouputStream); ouputStream.flush(); ouputStream.close(); } /** * 按順序設定表頭 * 工資由多個不同項組成 根據需要匯出的型別不同 設定表頭資訊 * @return */ private void setExcelHeader(HSSFRow headerRow,List<Salary> data) { headerRow.createCell(0).setCellValue("年份"); headerRow.createCell(1).setCellValue("月份"); if(StringUtils.isNotBlank(data.get(0).getWages())){ headerRow.createCell(2).setCellValue("應發額"); }else if(StringUtils.isNotBlank(data.get(0).getPostWage())){ headerRow.createCell(2).setCellValue("崗資"); }else if(StringUtils.isNotBlank(data.get(0).getPay())){ headerRow.createCell(2).setCellValue("薪資"); } . .此處省略多個情況判斷 . else if(StringUtils.isNotBlank(data.get(0).getMeritPay())){ headerRow.createCell(2).setCellValue("績效"); }else if(StringUtils.isNotBlank(data.get(0).getTask())){ headerRow.createCell(2).setCellValue("崗位津貼"); } } /** * 生成單元格 * * @param row * @param style * @param columnIndex * @param value */ private void createNewCell(HSSFRow row, HSSFCellStyle style, int columnIndex, String value) { if (row != null) { HSSFCell cell = row.createCell(columnIndex); cell.setCellStyle(style); if (value != null) { cell.setCellValue(value); } } } } }