easyExcel合并单元格导出
一、导入maven依赖
（很多旧项目自定义了一套Excel导出工具，poi版本可能不兼容，一般poi新旧版本不兼容分界线在3.17，选择3.17版本不会发生代码不兼容情况）
com.alibaba
easyexcel
2.2.6
org.apache.poi
poi
org.apache.poi
poi-ooxml
org.apache.poi
poi-ooxml-schemas
org.apache.poi
poi
3.17
org.apache.poi
poi-ooxml
3.17
org.apache.poi
poi-ooxml
3.17
sources
org.apache.commons
commons-collections4
4.1
二、重写easyExcel-自定义写入处理器
import com.alibaba.excel.metadata.Head;
import com.alibaba.excel.write.merge.AbstractMergeStrategy;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.util.CellRangeAddress;
import java.util.ArrayList;
import java.util.List;
/**
* 自定义合并策略 该类继承了AbstractMergeStrategy抽象合并策略，需要重写merge()方法
* @author reshui
* @date 2023/9/4
**/
public class CustomMergeStrategy extends AbstractMergeStrategy {
/**
* 分组，每几行合并一次
*/
private List exportFieldGroupCountList;
/**
* 目标合并列index
*/
private Integer targetColumnIndex;
/**
* 需要开始合并单元格的首行index
*/
private Integer rowIndex;
/**
* @param exportDataList exportDataList为待合并目标列的值
* @param targetColumnIndex 需要合并的列
* @return {@code }
* @author reshui
* @date 2023/09/05
*/
public CustomMergeStrategy(List exportDataList, Integer targetColumnIndex) {
this.exportFieldGroupCountList = getGroupCountList(exportDataList);
this.targetColumnIndex = targetColumnIndex;
}
@Override
protected void merge(Sheet sheet, Cell cell, Head head, Integer relativeRowIndex) {
if (null == rowIndex) {
rowIndex = cell.getRowIndex();
}
// 仅从首行以及目标列的单元格开始合并，忽略其他
if (cell.getRowIndex() == rowIndex && cell.getColumnIndex() == targetColumnIndex) {
mergeGroupColumn(sheet);
}
}
private void mergeGroupColumn(Sheet sheet) {
int rowCount = rowIndex;
for (Integer count : exportFieldGroupCountList) {
if (count == 1) {
rowCount += count;
continue;
}
// 合并单元格
CellRangeAddress cellRangeAddress = new CellRangeAddress(rowCount, rowCount + count - 1, targetColumnIndex, targetColumnIndex);
sheet.addMergedRegionUnsafe(cellRangeAddress);
rowCount += count;
}
}
/**
* 该方法将目标列根据值是否相同连续可合并，存储可合并的行数
* @param exportDataList
* @return {@code List }
* @author reshui
* @date 2023/09/05
*/
private List getGroupCountList(List exportDataList) {
if (CollectionUtils.isEmpty(exportDataList)) {
return new ArrayList<>();
}
List groupCountList = new ArrayList<>();
int count = 1;
for (int i = 1; i < exportDataList.size(); i++) {
if (exportDataList.get(i).equals(exportDataList.get(i - 1))) {
count++;
} else {
groupCountList.add(count);
count = 1;
}
}
// 处理完最后一条后
groupCountList.add(count);
return groupCountList;
}
} 三、导出工具类封装
import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.date.DateUtil;
import cn.hutool.core.io.FileUtil;
import cn.hutool.core.util.StrUtil;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.write.builder.ExcelWriterSheetBuilder;
import com.alibaba.excel.write.handler.WriteHandler;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.*;
/**
* 下载excel文件工具
*
* @author reshui
* @date 2023/09/05
*/
public class DownloadExcelUtil {
private static final Logger log = LoggerFactory.getLogger(DownloadExcelUtil.class);
private final static String separatorChar = "-";
public static void downloadFile(HttpServletResponse response, Class clazz, String data) throws IOException {
String timeStamp = DateUtil.format(DateUtil.date(), "yyyyMMddHHmmss");
String fileName = timeStamp + "-log";
downloadFile(response, clazz, data, fileName, "数据", null);
}
/**
* @param response 响应请求
* @param clazz 导出数据类型
* @param data 数据源
* @param customFileName 文件名
* @param sheetName 页名
* @param writeHandlerList 自定义写入处理器
* @return {@code T }
* @author reshui
* @date 2023/09/05
*/
public static T downloadFile(HttpServletResponse response, Class clazz
, String data
, String customFileName
, String sheetName
, List writeHandlerList) throws IOException {
// 这里注意 有同学反应使用swagger 会导致各种问题，请直接用浏览器或者用postman
try {
response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
response.setCharacterEncoding("utf-8");
// 这里URLEncoder.encode可以防止中文乱码 当然和easy-excel没有关系
String fileName = URLEncoder.encode(customFileName, "UTF-8").replaceAll("\\+", "%20");
response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
// 这里需要设置不关闭流
ExcelWriterSheetBuilder writerSheetBuilder = EasyExcel.write(response.getOutputStream(), clazz).autoCloseStream(Boolean.FALSE).sheet(sheetName);
if (CollUtil.isNotEmpty(writeHandlerList)) {
for (WriteHandler writeHandler : writeHandlerList) {
writerSheetBuilder.registerWriteHandler(writeHandler);
}
}
writerSheetBuilder.doWrite(JSONObject.parseArray(data, clazz));
} catch (Exception e) {
// 重置response
response.reset();
response.setContentType("application/json");
response.setCharacterEncoding("utf-8");
Map map = new HashMap<>(2);
map.put("status", "failure");
map.put("message", "下载文件失败" + e.getMessage());
response.getWriter().println(JSON.toJSONString(map));
}
return null;
}
/**
* 出把excel
*
* @param timeStamp 时间戳
* @param excelFileName excel文件名字
* @param headClassType 头类类型
* @param resultExcelList 结果excel表
* @param filePath 文件路径
* @author reshui
* @date 2023/02/15
*/
public static void outputExcelToLocal(String timeStamp, String excelFileName, Class headClassType, List resultExcelList, String filePath) {
//文件时间戳
timeStamp = Objects.nonNull(timeStamp) ? timeStamp : StrUtil.EMPTY;
String partFileName = filePath + File.separator + excelFileName + separatorChar + timeStamp + "-log.xlsx";
FileUtil.touch(partFileName);
EasyExcel.write(partFileName, headClassType).sheet("源数据").doWrite(resultExcelList);
}
/**
* 简单把excel
*
* @param excelFileName excel文件名字
* @param headClassType 头类类型
* @param resultExcelList 结果excel表
* @param filePath 文件路径
* @author reshui
* @date 2023/02/15
*/
public static void easyOutputExcelToLocal(String excelFileName, Class headClassType, List resultExcelList, String filePath) {
String timeStamp = DateUtil.format(DateUtil.date(), "yyyyMMddHHmmss");
outputExcelToLocal(timeStamp, excelFileName, headClassType, resultExcelList, filePath);
}
public static void main(String[] args) {
String timeStamp = DateUtil.format(DateUtil.date(), "yyyyMMddHHmmss");
String titleTmpDirPath = FileUtil.getTmpDirPath() + File.separator + "test" + File.separator + timeStamp + File.separator;
try {
System.out.println("日志存储地址-[" + titleTmpDirPath + "]");
log.info("日志存储[" + titleTmpDirPath + "]");
String partFileName = titleTmpDirPath + timeStamp + "-log.xlsx";
FileUtil.touch(partFileName);
EasyExcel.write(partFileName, String.class).sheet("源数据").doWrite(null);
} catch (Exception e) {
log.error("日志存储[" + titleTmpDirPath + "]" + "-error:", e);
}
}
}
四、运行
@RestController
@RequestMapping("/check")
public class TestController {
@RequestMapping(value = "/run1",method = {RequestMethod.GET})
public void run1(HttpServletResponse response) throws IOException {
List demoDataList = data1();
List customMergeStrategies = Arrays.asList(
new CustomMergeStrategy(demoDataList.stream().map(DemoData::getName).collect(Collectors.toList()), 1));
DownloadExcelUtil.downloadFile(response,DemoData.class, JSONObject.toJSONString(demoDataList),"测试","页1"
, customMergeStrategies);
}
public static List data1(){
List demoDataList = new ArrayList<>();
DemoData demoData0 = new DemoData();
demoData0.setId("0");
demoData0.setName("hello0");
demoDataList.add(demoData0);
DemoData demoData1 = new DemoData();
demoData1.setId("1");
demoData1.setName("hello1");
demoDataList.add(demoData1);
DemoData demoData11 = new DemoData();
demoData11.setId("1");
demoData11.setName("hello1");
demoDataList.add(demoData11);
DemoData demoData2 = new DemoData();
demoData2.setId("2");
demoData2.setName("hello2");
demoDataList.add(demoData2);
return demoDataList;
}
}