一、引入依赖

		<!--读取excel文件,配置POI框架的依赖--><dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>3.17</version></dependency><dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>3.17</version></dependency>

二、数据对象ExcelDataVO

/*** Description: 读取Excel时，封装读取的每一行的数据*/
public class ExcelDataVO {/*** 姓名*/private String name;/*** 年龄*/private Integer age;/*** 居住地*/private String location;/*** 职业*/private String job;public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getLocation() {return location;}public void setLocation(String location) {this.location = location;}public String getJob() {return job;}public void setJob(String job) {this.job = job;}@Overridepublic String toString() {return "ExcelDataVO{" +"name='" + name + '\'' +", age=" + age +", location='" + location + '\'' +", job='" + job + '\'' +'}';}
}

三、读取Excel文件类ExcelReader

public class ExcelReader {private static Logger logger = Logger.getLogger(ExcelReader.class.getName()); // 日志打印类private static final String XLS = "xls";private static final String XLSX = "xlsx";/*** 读取Excel文件内容* @param fileName 要读取的Excel文件所在路径* @return 读取结果列表，读取失败时返回null*/public static List<ExcelDataVO> readExcel(String fileName) {Workbook workbook = null;FileInputStream inputStream = null;try {// 获取Excel后缀名String fileType = fileName.substring(fileName.lastIndexOf(".") + 1, fileName.length());// 获取Excel文件File excelFile = new File(fileName);if (!excelFile.exists()) {logger.warning("指定的Excel文件不存在！");return null;}// 获取Excel工作簿inputStream = new FileInputStream(excelFile);workbook = getWorkbook(inputStream, fileType);// 读取excel中的数据List<ExcelDataVO> resultDataList = parseExcel(workbook);return resultDataList;} catch (Exception e) {logger.warning("解析Excel失败，文件名：" + fileName + " 错误信息：" + e.getMessage());return null;} finally {try {if (null != workbook) {workbook.close();}if (null != inputStream) {inputStream.close();}} catch (Exception e) {logger.warning("关闭数据流出错！错误信息：" + e.getMessage());return null;}}}/*** 根据文件后缀名类型获取对应的工作簿对象* @param inputStream 读取文件的输入流* @param fileType 文件后缀名类型（xls或xlsx）* @return 包含文件数据的工作簿对象* @throws IOException*/public static Workbook getWorkbook(InputStream inputStream, String fileType) throws IOException {Workbook workbook = null;if(fileType.equalsIgnoreCase(XLS)){workbook = new XSSFWorkbook(inputStream);}else if(fileType.equalsIgnoreCase(XLSX)){workbook = new HSSFWorkbook(inputStream);}return workbook;}/*** 解析Excel数据* @param workbook Excel工作簿对象* @return 解析结果*/private static List<ExcelDataVO> parseExcel(Workbook workbook) {List<ExcelDataVO> resultDataList = new ArrayList<ExcelDataVO>();// 解析sheetfor (int sheetNum = 0; sheetNum < workbook.getNumberOfSheets(); sheetNum++) {Sheet sheet = workbook.getSheetAt(sheetNum);// 校验sheet是否合法if (sheet == null) {continue;}// 获取第一行数据int firstRowNum = sheet.getFirstRowNum();Row firstRow = sheet.getRow(firstRowNum);if (null == firstRow) {logger.warning("解析Excel失败，在第一行没有读取到任何数据！");}// 解析每一行的数据，构造数据对象int rowStart = firstRowNum + 1;int rowEnd = sheet.getPhysicalNumberOfRows();for (int rowNum = rowStart; rowNum < rowEnd; rowNum++) {Row row = sheet.getRow(rowNum);if (null == row) {continue;}ExcelDataVO resultData = convertRowToData(row);if (null == resultData) {logger.warning("第 " + row.getRowNum() + "行数据不合法，已忽略！");continue;}resultDataList.add(resultData);}}return resultDataList;}/*** 提取每一行中需要的数据，构造成为一个结果数据对象** 当该行中有单元格的数据为空或不合法时，忽略该行的数据** @param row 行数据* @return 解析后的行数据对象，行数据错误时返回null*/private static ExcelDataVO convertRowToData(Row row) {ExcelDataVO resultData = new ExcelDataVO();Cell cell;int cellNum = 0;// 获取姓名cell = row.getCell(cellNum++);String name = convertCellValueToString(cell);resultData.setName(name);// 获取年龄cell = row.getCell(cellNum++);String ageStr = convertCellValueToString(cell);if (null == ageStr || "".equals(ageStr)) {// 年龄为空resultData.setAge(null);} else {resultData.setAge(Integer.parseInt(ageStr));}// 获取居住地cell = row.getCell(cellNum++);String location = convertCellValueToString(cell);resultData.setLocation(location);// 获取职业cell = row.getCell(cellNum++);String job = convertCellValueToString(cell);resultData.setJob(job);return resultData;}/*** 将单元格内容转换为字符串* @param cell* @return*/private static String convertCellValueToString(Cell cell) {if(cell==null){return null;}String returnValue = null;switch (cell.getCellTypeEnum()) {case NUMERIC:   //数字Double doubleValue = cell.getNumericCellValue();// 格式化科学计数法，取一位整数DecimalFormat df = new DecimalFormat("0");returnValue = df.format(doubleValue);break;case STRING:    //字符串returnValue = cell.getStringCellValue();break;case BOOLEAN:   //布尔Boolean booleanValue = cell.getBooleanCellValue();returnValue = booleanValue.toString();break;case BLANK:     // 空值break;case FORMULA:   // 公式returnValue = cell.getCellFormula();break;case ERROR:     // 故障break;default:break;}return returnValue;}}

四、生成Excel并写入数据信息ExcelWriter

public class ExcelWriter {private static List<String> CELL_HEADS; //列头static{// 类装载时就载入指定好的列头信息，如有需要，可以考虑做成动态生成的列头CELL_HEADS = new ArrayList<String>();CELL_HEADS.add("姓名");CELL_HEADS.add("年龄");CELL_HEADS.add("居住城市");CELL_HEADS.add("职业");}/*** 生成Excel并写入数据信息* @param dataList 数据列表* @return 写入数据后的工作簿对象*/public static Workbook exportData(List<ExcelDataVO> dataList){// 生成xlsx的ExcelWorkbook workbook = new SXSSFWorkbook();// 如需生成xls的Excel，请使用下面的工作簿对象，注意后续输出时文件后缀名也需更改为xls//Workbook workbook = new HSSFWorkbook();// 生成Sheet表，写入第一行的列头Sheet sheet = buildDataSheet(workbook);//构建每行的数据内容int rowNum = 1;for (Iterator<ExcelDataVO> it = dataList.iterator(); it.hasNext(); ) {ExcelDataVO data = it.next();if (data == null) {continue;}//输出行数据Row row = sheet.createRow(rowNum++);convertDataToRow(data, row);}return workbook;}/*** 生成sheet表，并写入第一行数据（列头）* @param workbook 工作簿对象* @return 已经写入列头的Sheet*/private static Sheet buildDataSheet(Workbook workbook) {Sheet sheet = workbook.createSheet();// 设置列头宽度for (int i=0; i<CELL_HEADS.size(); i++) {sheet.setColumnWidth(i, 4000);}// 设置默认行高sheet.setDefaultRowHeight((short) 400);// 构建头单元格样式CellStyle cellStyle = buildHeadCellStyle(sheet.getWorkbook());// 写入第一行各列的数据Row head = sheet.createRow(0);for (int i = 0; i < CELL_HEADS.size(); i++) {Cell cell = head.createCell(i);cell.setCellValue(CELL_HEADS.get(i));cell.setCellStyle(cellStyle);}return sheet;}/*** 设置第一行列头的样式* @param workbook 工作簿对象* @return 单元格样式对象*/private static CellStyle buildHeadCellStyle(Workbook workbook) {CellStyle style = workbook.createCellStyle();//对齐方式设置style.setAlignment(HorizontalAlignment.CENTER);//边框颜色和宽度设置style.setBorderBottom(BorderStyle.THIN);style.setBottomBorderColor(IndexedColors.BLACK.getIndex()); // 下边框style.setBorderLeft(BorderStyle.THIN);style.setLeftBorderColor(IndexedColors.BLACK.getIndex()); // 左边框style.setBorderRight(BorderStyle.THIN);style.setRightBorderColor(IndexedColors.BLACK.getIndex()); // 右边框style.setBorderTop(BorderStyle.THIN);style.setTopBorderColor(IndexedColors.BLACK.getIndex()); // 上边框//设置背景颜色style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());style.setFillPattern(FillPatternType.SOLID_FOREGROUND);//粗体字设置Font font = workbook.createFont();font.setBold(true);style.setFont(font);return style;}/*** 将数据转换成行* @param data 源数据* @param row 行对象* @return*/private static void convertDataToRow(ExcelDataVO data, Row row){int cellNum = 0;Cell cell;// 姓名cell = row.createCell(cellNum++);cell.setCellValue(null == data.getName() ? "" : data.getName());// 年龄cell = row.createCell(cellNum++);if (null != data.getAge()) {cell.setCellValue(data.getAge());} else {cell.setCellValue("");}// 所在城市cell = row.createCell(cellNum++);cell.setCellValue(null == data.getLocation() ? "" : data.getLocation());// 职业cell = row.createCell(cellNum++);cell.setCellValue(null == data.getJob() ? "" : data.getJob());}
}

五、测试类

public class Main {private static Logger logger = Logger.getLogger(Main.class.getName());public static void main(String[] args) {testExcelWriter();
//        testExcelReader();}static void testExcelWriter(){// 创建需要写入的数据列表List<ExcelDataVO> dataVOList = new ArrayList<ExcelDataVO>(2);ExcelDataVO dataVO = new ExcelDataVO();dataVO.setName("小明");dataVO.setAge(18);dataVO.setLocation("广州");dataVO.setJob("大学生");ExcelDataVO dataVO2 = new ExcelDataVO();dataVO2.setName("小花");dataVO2.setAge(19);dataVO2.setLocation("深圳");dataVO2.setJob("大学生");dataVOList.add(dataVO);dataVOList.add(dataVO2);// 写入数据到工作簿对象内Workbook workbook = ExcelWriter.exportData(dataVOList);// 以文件的形式输出工作簿对象FileOutputStream fileOut = null;try {String exportFilePath = "D:\\下载\\aa.xls";File exportFile = new File(exportFilePath);if (!exportFile.exists()) {exportFile.createNewFile();}fileOut = new FileOutputStream(exportFilePath);workbook.write(fileOut);fileOut.flush();} catch (Exception e) {logger.warning("输出Excel时发生错误，错误原因：" + e.getMessage());} finally {try {if (null != fileOut) {fileOut.close();}if (null != workbook) {workbook.close();}} catch (IOException e) {logger.warning("关闭输出流时发生错误，错误原因：" + e.getMessage());}}}static void testExcelReader(){// 设定Excel文件所在路径String excelFileName = "D:\\下载\\aa.xls";// 读取Excel文件内容List<ExcelDataVO> readResult = ExcelReader.readExcel(excelFileName);System.out.println(readResult.toString());// todo 进行业务操作}
}