EasyExcel 通过模板填充数据

EasyExcel 通过模板填充数据两种方式：1、直接通过模板填充。2、通过IO流填充。

模板示例
注意：单个字段填充只写字段名即可，数据集填充需要在字段前加 .

代码示例：

package com.service.single.example.excel;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.EasyExcelFactory;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.support.ExcelTypeEnum;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.alibaba.excel.write.metadata.fill.FillConfig;
import com.service.single.entity.SystemUser;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
 * @Author: 一休
 * @Date: 2025/2/10
 */
public class ExcelTemplate {
 public static void main(String[] args) throws IOException {
 // 准备数据
 List<SystemUser> users = new ArrayList<>();
 SystemUser user1 = new SystemUser();
 user1.setUsername("张三");
 user1.setNickname("zhangsan");
 user1.setPhone("11111");
 users.add(user1);
 SystemUser user2 = new SystemUser();
 user2.setUsername("张三");
 user2.setNickname("zhangsan");
 user2.setPhone("11111");
 users.add(user2);
 // 单个字段填充，使用map格式
 Map<String, Object> otherData = new HashMap<>();
 otherData.put("title", "系统用户表");
 // 模板文件路径
 String templateFileName = "src/main/resources/template.xlsx";
 DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");
 String formattedDateTime = LocalDateTime.now().format(formatter);
 // 输出文件路径
 String outputFileName = "src/main/resources/filled_template_" + formattedDateTime + ".xlsx";
 // 输出文件路径
 String outputFileName1 = "src/main/resources/filled_template1_" + formattedDateTime + ".xlsx";
 // 1、直接通过文件模板填充
 try (ExcelWriter excelWriter = EasyExcel.write(outputFileName).withTemplate(templateFileName).build();) {
 // 创建写入工作表
 WriteSheet writeSheet = EasyExcel.writerSheet().build();
 // 每次使用 list 参数时创建新行。
 FillConfig fillConfig = FillConfig.builder().forceNewRow(true).build();
 // 针对某个字段填充
 excelWriter.fill(otherData, fillConfig, writeSheet);
 // 填充集合
 excelWriter.fill(users, fillConfig, writeSheet);
 }
 // 2、通过IO流填充
 try (
 // 使用 try-with-resources 管理输入流
 InputStream inputStream = Files.newInputStream(Paths.get(templateFileName));
 InputStream templateInputStream = new BufferedInputStream(inputStream);
 ByteArrayOutputStream outputStream = new ByteArrayOutputStream()
 ) {
 try (
 // 创建 ExcelWriter 对象
 ExcelWriter excelWriter = EasyExcelFactory.write(outputStream).excelType(ExcelTypeEnum.XLSX).withTemplate(templateInputStream).build()
 ) {
 WriteSheet writeSheet = EasyExcelFactory.writerSheet().sheetNo(0).build();
 WriteSheet writeSheet1 = EasyExcelFactory.writerSheet().sheetNo(1).build();
 FillConfig fillConfig = FillConfig.builder().forceNewRow(Boolean.TRUE).build();
 // 针对某个字段填充
 excelWriter.fill(otherData, fillConfig, writeSheet);
 // 填充集合
 excelWriter.fill(users, fillConfig, writeSheet);
 // 指定sheet填充数据
 excelWriter.fill(users, fillConfig, writeSheet1);
 }
 try (
 FileOutputStream fileOutputStream = new FileOutputStream(outputFileName1)
 ) {
 outputStream.writeTo(fileOutputStream);
 // 刷新 FileOutputStream 缓冲区，确保数据全部写入文件
 fileOutputStream.flush();
 System.out.println("文件生成成功: " + outputFileName1);
 }
 }
 }
}