工具类：
package com.test.word; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.OutputStream; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.ss.usermodel.Cell; import org.apache.poi.ss.usermodel.CellStyle; import org.apache.poi.ss.usermodel.CreationHelper; import org.apache.poi.ss.usermodel.Font; 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.XSSFCell; import org.apache.poi.xssf.usermodel.XSSFCellStyle; import org.apache.poi.xssf.usermodel.XSSFDataFormat; import org.apache.poi.xssf.usermodel.XSSFRichTextString; import org.apache.poi.xssf.usermodel.XSSFRow; import org.apache.poi.xssf.usermodel.XSSFSheet; import org.apache.poi.xssf.usermodel.XSSFWorkbook; /** * excle工具类 * * @author xieh 2019/11/24 使用的jar包是：poi-4.1.0.jar 和 poi-ooxml-4.1.0.jar * */ public class Excel { /** * 此方法兼容.xls 和 .xlsx格式，建议使用 * @param path excle文件路径 * @param sheetIndex excle文件的Sheet页的下标，从0开始 * @return excle表中的内容 * @throws Exception */ @SuppressWarnings("resource") public static List<Map<String, String>> excelXRead(String path,int sheetIndex) throws Exception { //用流的方式先读取到你想要的excel的文件 //FileInputStream fis=new FileInputStream(new File(System.getProperty("user.dir")+"/src/excel.xls")); File excel = new File(path); String[] split = excel.getName().split("\."); //.是特殊字符，需要转义 Workbook wb = null; FileInputStream fis = null; //根据文件后缀（xls/xlsx）进行判断 if ( "xls".equals(split[1])){ fis = new FileInputStream(excel); //文件流对象 wb = new HSSFWorkbook(fis); }else if ("xlsx".equals(split[1])){ wb = new XSSFWorkbook(excel); }else { System.out.println("文件类型错误!"); return new ArrayList<>(); } //开始解析 Sheet sheet = wb.getSheetAt(sheetIndex); //读取sheet 0 // 获取第一行 int firstrow = sheet.getFirstRowNum() + 1; //第一行是字段名，把第一行去掉 // 获取最后一行 int lastrow = sheet.getLastRowNum(); // 存取最后结果 List<Map<String, String>> result = new ArrayList<Map<String, String>>(); // 获取第一行(含有字段名) Row rowFirst = sheet.getRow(sheet.getFirstRowNum()); // 循环行数依次获取列数 for (int i = firstrow; i < lastrow + 1; i++) { // 获取哪一行i Row row = sheet.getRow(i); // 存放每行的键值对结果 Map<String, String> tempMap = new HashMap<String, String>(); if (row != null) { // 获取这一行的第一列 int firstcell = row.getFirstCellNum(); // 获取这一行的最后一列 int lastcell = row.getLastCellNum(); // 创建一个集合，用处将每一行的每一列数据都存入集合中 //List<String> list = new ArrayList<String>(); for (int j = firstcell; j < lastcell; j++) { // 获取第j列 Cell cell = row.getCell(j); if (cell != null && !("").equals(cell.toString())) { //System.out.print(cell + " "); //list.add(cell.toString()); tempMap.put(rowFirst.getCell(j).toString(), cell.toString().trim()); } } // 存放每行的结果 result.add(tempMap); }// row if end }// for end if(null != fis){ fis.close(); } System.out.println(result.toString()); return result; } /** * 创建和写入excle内容 * @param exportList 实体类list * @param file 生成的文件路径 * @throws Exception */ public static void writeXls(List<Test> exportList, File file) throws Exception { String[] options = { "ID", "内容", "名字" }; XSSFWorkbook book = new XSSFWorkbook(); CreationHelper createHelper = book.getCreationHelper(); XSSFCellStyle style = book.createCellStyle(); XSSFCellStyle dateStyle = book.createCellStyle(); XSSFDataFormat format = book.createDataFormat(); style.setWrapText(true); dateStyle.setWrapText(true); XSSFSheet sheet = book.createSheet("sheet"); sheet.setColumnWidth(3, 13000); sheet.setDefaultColumnWidth(20); XSSFRow firstRow = sheet.createRow(0); XSSFCell[] firstCells = new XSSFCell[3]; CellStyle styleBlue = book.createCellStyle(); // 样式对象 // 设置单元格的背景颜色为淡蓝色 styleBlue.setWrapText(true);// 指定当单元格内容显示不下时自动换行 Font font = book.createFont(); //font.setBoldweight(Font.BOLDWEIGHT_BOLD); font.setFontName("宋体"); font.setFontHeight((short) 280); style.setFont(font); dateStyle.setFont(font); dateStyle.setDataFormat(format.getFormat("yyyy-mm-dd")); styleBlue.setFont(font); for (int j = 0; j < options.length; j++) { firstCells[j] = firstRow.createCell(j); firstCells[j].setCellStyle(styleBlue); firstCells[j].setCellValue(new XSSFRichTextString(options[j])); } getExport(sheet, style, createHelper, exportList, dateStyle); if (file.exists()) { file.delete(); } file.createNewFile(); OutputStream os = new FileOutputStream(file); book.write(os); os.close(); } /** * excle实体数据写入 * @param sheet * @param style * @param createHelper * @param exportList * @param dateStyle */ private static void getExport(XSSFSheet sheet, XSSFCellStyle style, CreationHelper createHelper, List<Test> exportList, XSSFCellStyle dateStyle) { // 遍历实例类的list集合 for (int i = 0; i < exportList.size(); i++) { // 创建行 XSSFRow row = sheet.createRow(i + 1); // 实体类 Test export = exportList.get(i); // 第一列 XSSFCell hotelId = row.createCell(0); hotelId.setCellStyle(style); // 第二列 XSSFCell hotelName = row.createCell(1); hotelName.setCellStyle(dateStyle); // 第三列 XSSFCell chargeCount = row.createCell(2); chargeCount.setCellStyle(style); // 设置值 hotelId.setCellValue(export.getId()); hotelName.setCellValue("测试"); chargeCount.setCellValue(export.getName()); // ta.append("写入excel开始,行数是" + (i + 1) + " "); }// for end } /** * 测试 * * @param args */ public static void main(String[] args) { try { //List<Map<String, String>> excelXRead = Excel.excelXRead("E:/2.xlsx", 0); List<Map<String, String>> excelXRead = Excel.excelXRead("E:/4.xls", 0); System.out.println(excelXRead.toString()); /* List<Test> show = new ArrayList<Test>(); Test test1 = new Test(); test1.setId(1); test1.setName("xieh"); Test test2 = new Test(); test2.setId(2); test2.setName("xieh"); show.add(test1); show.add(test2); Excel.writeXls(show, new File("D:/bbb.xls")); Excel.writeXls(show, new File("D:/aaa.xlsx")); */ } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } }
运行结果：
excle数据：
参考文章：