Apache POI报表Utils

Apache POI报表工具类

package com.itheima.utils; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.List; 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; public class POIUtils { private final static String xls = "xls"; private final static String xlsx = "xlsx"; private final static String DATE_FORMAT = "yyyy/MM/dd"; /** * 读入excel文件，解析后返回 * @param file * @throws IOException */ 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(); //循环除了第一行的所有行 for(int rowNum = firstRowNum+1;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; } //校验文件是否合法 public static void checkFile(MultipartFile file) throws IOException{ //判断文件是否存在 if(null == file){ 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)){ 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) { e.printStackTrace(); } return workbook; } public static String getCellValue(Cell cell){ String cellValue = ""; if(cell == null){ return cellValue; } //如果当前单元格内容为日期类型，需要特殊处理 String dataFormatString = cell.getCellStyle().getDataFormatString(); if(dataFormatString.equals("m/d/yy")){ cellValue = new SimpleDateFormat(DATE_FORMAT).format(cell.getDateCellValue()); 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; } }