Spring MVC實現將資料匯出為Excel檔案

1. 宣告介面，通過實現該介面實現將模型中的資料寫入Workbook中

   public interface ExcelExportService {
   
      void makeWorkBook(Map<String, Object> model, Workbook workBook);
   
   }

2. 建立自定義的檢視類繼承org.springframework.web.servlet.view.document.AbstractXlsView抽象類，並且實現抽象方法buildExcelDocument(…)方法。

public class
 
 ExcelView extends AbstractXlsView {


    private String filename = null;
    /*自定義的介面，實現將資料模型中的資料寫入Workbook中*/
    private ExcelExportService excelExpService = null;

    public ExcelView(ExcelExportService excelExpService) {
        this.excelExpService = excelExpService;
    }

    public ExcelView
 
(String filename, ExcelExportService excelExpService) {
        this.filename = filename;
        this.excelExpService = excelExpService;
    }

    @Override
    protected void buildExcelDocument(Map<String, Object> model, Workbook workbook
            , HttpServletRequest request, HttpServletResponse response) throws
 
 Exception {
        if (excelExpService == null) {
            throw new RuntimeException("到處服務介面不能為null");
        }
        // 檔名不為空，則設定下載時的檔名；否則，使用路徑的名字
        if (!StringUtils.isEmpty(filename)) {
            String reqCharset = request.getCharacterEncoding();
            reqCharset = reqCharset == null ? "UTF-8" : reqCharset;
            filename = new String(filename.getBytes(reqCharset), "ISO8859-1");
            response.setHeader("Content-disposition", "attachment;filename=" + filename);
        }
        excelExpService.makeWorkBook(model, workbook);
    }
    -----------getter and setter-----------
}

1. 建立一個方法實現自定義的介面ExcelExportService

   private ExcelExportService exportService() {
      //使用Lambda表示式自定義匯出excel規則
      return (Map<String, Object> model, Workbook workbook) -> {
          //獲取使用者列表
          List<Role> roleList = (List<Role>) model.get("roleList");
          //生成Sheet
          Sheet sheet= workbook.createSheet("所有角色");
          //載入標題
          Row title = sheet.createRow(0);
          title.createCell(0).setCellValue("編號");
          title.createCell(1).setCellValue("名稱");
          title.createCell(2).setCellValue("備註");
          //便利角色列表，生成一行行的資料
          for (int i=0; i<roleList.size(); i++) {
              Role role = roleList.get(i);
              int rowIdx = i + 1;
              Row row = sheet.createRow(rowIdx);
              row.createCell(0).setCellValue(role.getId());
              row.createCell(1).setCellValue(role.getRoleName());
              row.createCell(2).setCellValue(role.getNote());
          }
      };
   }

2. 在Controller中呼叫

   @RequestMapping(value = "/export", method = RequestMethod.GET)
   public ModelAndView exportRoles() {
      ModelAndView mv = new ModelAndView();
      // 建立檢視
      ExcelView ev = new ExcelView(exportService());
      ev.setFilename("所有角色.xls");
      // 構造查詢資料庫引數
      RoleParam roleParam = new RoleParam();
      PageParam pageParam = new PageParam();
      pageParam.setStart(0);
      pageParam.setLimit(100);
      roleParam.setPageParam(pageParam);
      // 查詢資料庫
      List<Role> roles = iRoleService.findRoles(roleParam);
      // 將資料放入模型中
      mv.addObject("roleList", roles);
      mv.setView(ev);
      return mv;
   }