整理了下Hutool导入导出的简单使用。

导入maven或jar包（注意这里导入的poi只是为了优化样式）

<!-- https://mvnrepository.com/artifact/cn.hutool/hutool-all -->
<dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>5.3.0</version>
</dependency><!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>4.0.1</version>
</dependency>

代码部分：

import cn.hutool.core.io.FileUtil;
import cn.hutool.poi.excel.ExcelReader;
import cn.hutool.poi.excel.ExcelUtil;
import cn.hutool.poi.excel.ExcelWriter;
import org.apache.poi.ss.usermodel.*;import javax.servlet.ServletOutputStream;
import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;/*** hutool测试（导入导出）*/
public class HutoolTest {public static void main(String[] args) {//导出exportExcel();//导入importExcel();}/*** 导出*/private static void exportExcel(){//本地导出的路径String exportPath = "E:/测试图片/测试.xlsx";try{//处理表头对应数据List<String> titleList = new LinkedList<>();titleList.add("姓名");titleList.add("年龄");titleList.add("地点");// 创建一些数据List<List<String>> data = new ArrayList<>();data.add(Arrays.asList("张三", "25", "北京"));data.add(Arrays.asList("李四", "30", "上海"));// 通过工具类创建writerExcelWriter writer = new ExcelWriter();// 一次性写出内容，使用默认样式，强制输出标题writer.writeHeadRow((Iterable<?>) titleList);// 写入内容writer.write(data);//设置表头宽度setSizeColumnBt(writer.getSheet(),titleList.size());Workbook workbook = writer.getWorkbook();//服务器上返回时
//            response.setContentType("application/vnd.ms-excel;charset=ISO-8859-1");
//            filename = new String(filename.getBytes("GB2312"), "ISO8859-1");
//            response.setHeader("content-disposition", "attachment;filename=" + filename);
//            response.addHeader("Pargam", "no-cache");
//            response.addHeader("Cache-Control", "no-cache");
//            ServletOutputStream sout = response.getOutputStream();//本地导出时ByteArrayOutputStream sout = new ByteArrayOutputStream();workbook.write(sout);InputStream input = new ByteArrayInputStream(sout.toByteArray());// 测试导出到本地writeToLocal(exportPath,input);System.out.println("导出完成");// 关闭writer，释放内存writer.close();workbook.close();sout.flush();sout.close();} catch (Exception e) {e.printStackTrace();}}/*** 导入*/private static void importExcel(){//本地导入的路径String importPath = "E:/测试图片/测试.xlsx";// 指定 Excel 文件路径（正常是通过input流转）File excelFile = FileUtil.file(importPath);// 创建 ExcelReader 对象ExcelReader reader = ExcelUtil.getReader(excelFile);// 读取第一个sheet的数据List<List<Object>> data = reader.read();for (List<Object> data1 : data){System.out.println(data1.toString());}}/*** 自适应宽度(中文支持)（表头）** @param sheet sheet* @param cellSize  因为for循环从0开始，size值为 列数-1*/private static void setSizeColumnBt(Sheet sheet, int cellSize) {for (int columnNum = 0; columnNum <= cellSize; columnNum++) {int columnWidth = sheet.getColumnWidth(columnNum) / 256;Row currentRow = sheet.getRow(0);if (currentRow.getCell(columnNum) != null) {Cell currentCell = currentRow.getCell(columnNum);if (currentCell.getCellType() == CellType.STRING) {int length = currentCell.getStringCellValue().getBytes().length;if (columnWidth < length + 1) {columnWidth = length + 8;}}}sheet.setColumnWidth(columnNum, columnWidth * 256);}}/*** 将InputStream写入本地文件* @param destination 写入本地目录* @param input 输入流* @throws IOException IOException*/public static void writeToLocal(String destination, InputStream input)throws IOException {int index;byte[] bytes = new byte[1024];FileOutputStream downloadFile = new FileOutputStream(destination);while ((index = input.read(bytes)) != -1) {downloadFile.write(bytes, 0, index);downloadFile.flush();}input.close();downloadFile.close();}
}

导出结果截图：

导入结果打印：

[姓名, 年龄, 地点]
[张三, 25, 北京]
[李四, 30, 上海]