POI之Excel导入

1，maven配置

 <dependency>
     <groupId>org.apache.poi</groupId>
     <artifactId>poi-ooxml</artifactId>
     <version>${poi.version}</version>
 </dependency>

2，Controller层

 /**
      * Excel导入数据
      * @return
      */
     @ResponseBody
     @RequestMapping(value="importExcel", method={RequestMethod.GET, RequestMethod.POST})
     public String importExcel(HttpServletRequest request, String name) {
         JSONObject result = new JSONObject();
         result.put("code", 0);
         result.put("msg", "导入成功！");
         //初始化解析器
         CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(request.getServletContext());
         //解析form中是否有enctype="multipart/form-data"
         try {
             if (multipartResolver.isMultipart(request)) {
                 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
                 Iterator iterator = multipartRequest.getFileNames();
                 while (iterator.hasNext()) {
                     MultipartFile multipartFile = multipartRequest.getFile(iterator.next().toString());
                     List<String[]> data = GhPOIUtils.readExcel(multipartFile);
                     Method method = IExportExcelService.class.getDeclaredMethod(name + "Import", new Class[]{List.class});
                     method.invoke(exportExcelService, data);
                 }
             }
         } catch(Exception e) {
             result.put("code", -1);
             result.put("msg", e.getMessage());
         }
         return result.toString();
     }

3，Util

 package com.smart.produce.core.utils.comm;
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;  
 
 import org.apache.log4j.Logger;
 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 import org.apache.poi.ss.usermodel.Cell;
 import org.apache.poi.ss.usermodel.Row;
 import org.apache.poi.ss.usermodel.Sheet;
 import org.apache.poi.ss.usermodel.Workbook;
 import org.apache.poi.xssf.usermodel.XSSFWorkbook;
 import org.springframework.web.multipart.MultipartFile;
 /**
  * excel读写工具类 */
 public class GhPOIUtils {
     private static Logger logger  = Logger.getLogger(GhPOIUtils.class);
     private final static String xls = "xls";
     private final static String xlsx = "xlsx";  
 
     public static void checkFile(MultipartFile file) throws IOException{
         //判断文件是否存在
         if(null == file){
             logger.error("文件不存在！");
             throw new FileNotFoundException("文件不存在！");
         }
         //获得文件名
         String fileName = file.getOriginalFilename();
         //判断文件是否是excel文件
         if(!fileName.endsWith(xls) && !fileName.endsWith(xlsx)){
             logger.error(fileName + "不是excel文件");
             throw new IOException(fileName + "不是excel文件");
         }
     }
 
     public static Workbook getWorkBook(MultipartFile file) {
         //获得文件名
         String fileName = file.getOriginalFilename();
         //创建Workbook工作薄对象，表示整个excel
         Workbook workbook = null;
         try {
             //获取excel文件的io流
             InputStream is = file.getInputStream();
             //根据文件后缀名不同(xls和xlsx)获得不同的Workbook实现类对象
             if(fileName.endsWith(xls)){
                 //2003
                 workbook = new HSSFWorkbook(is);
             }else if(fileName.endsWith(xlsx)){
                 //2007
                 workbook = new XSSFWorkbook(is);
             }
         } catch (IOException e) {
             logger.info(e.getMessage());
         }
         return workbook;
     }
 
     public static String getCellValue(Cell cell){
         String cellValue = "";
         if(cell == null){
             return cellValue;
         }
         //把数字当成String来读，避免出现1读成1.0的情况
         if(cell.getCellType() == Cell.CELL_TYPE_NUMERIC){
             cell.setCellType(Cell.CELL_TYPE_STRING);
         }
         //判断数据的类型
         switch (cell.getCellType()){
             case Cell.CELL_TYPE_NUMERIC: //数字
                 cellValue = String.valueOf(cell.getNumericCellValue());
                 break;
             case Cell.CELL_TYPE_STRING: //字符串
                 cellValue = String.valueOf(cell.getStringCellValue());
                 break;
             case Cell.CELL_TYPE_BOOLEAN: //Boolean
                 cellValue = String.valueOf(cell.getBooleanCellValue());
                 break;
             case Cell.CELL_TYPE_FORMULA: //公式
                 cellValue = String.valueOf(cell.getCellFormula());
                 break;
             case Cell.CELL_TYPE_BLANK: //空值
                 cellValue = "";
                 break;
             case Cell.CELL_TYPE_ERROR: //故障
                 cellValue = "非法字符";
                 break;
             default:
                 cellValue = "未知类型";
                 break;
         }
         return cellValue;
     }
 
     /**
      * 读入excel文件，解析后返回
      * @param file
      */
     public static List<String[]> readExcel(MultipartFile file) throws IOException{
         //检查文件
         checkFile(file);
         //获得Workbook工作薄对象
         Workbook workbook = getWorkBook(file);
         //创建返回对象，把每行中的值作为一个数组，所有行作为一个集合返回
         List<String[]> list = new ArrayList<String[]>();
         if(workbook != null){
             for(int sheetNum = 0;sheetNum < workbook.getNumberOfSheets();sheetNum++){
                 //获得当前sheet工作表
                 Sheet sheet = workbook.getSheetAt(sheetNum);
                 if(sheet == null){
                     continue;
                 }
                 //获得当前sheet的开始行
                 int firstRowNum  = sheet.getFirstRowNum();
                 //获得当前sheet的结束行
                 int lastRowNum = sheet.getLastRowNum();
                 //循环所有行
                 for(int rowNum = firstRowNum;rowNum <= lastRowNum;rowNum++){
                     //获得当前行
                     Row row = sheet.getRow(rowNum);
                     if(row == null){
                         continue;
                     }
                     //获得当前行的开始列
                     int firstCellNum = row.getFirstCellNum();
                     //获得当前行的列数
                     int lastCellNum = row.getPhysicalNumberOfCells();
                     String[] cells = new String[row.getPhysicalNumberOfCells()];
                     //循环当前行
                     for(int cellNum = firstCellNum; cellNum < lastCellNum;cellNum++){
                         Cell cell = row.getCell(cellNum);
                         cells[cellNum] = getCellValue(cell);
                     }
                     list.add(cells);
                 }
             }
             workbook.close();
         }
         return list;
     }
 }