java 导出excel 创建多级表头 Easyexcel web下载

maven依赖

  
    <dependency> <groupId>com.alibaba 
     groupId> <artifactId>easyexcel 
      artifactId> <version>2.1.1 
       version> <scope>test 
        scope>  
         dependency> <dependency> <groupId>com.alibaba 
          groupId> <artifactId>easyexcel 
           artifactId> <version>2.1.1 
            version> <scope>compile 
             scope>  
              dependency> 

使用对象创建

 import com.alibaba.excel.annotation.ExcelIgnore; import com.alibaba.excel.annotation.ExcelProperty; import lombok.Data; import java.util.Date; //导出数据成excel 多级头导出 配合测试类 @Data public class DemoData { 
    @ExcelProperty({ 
   "序号"}) private Integer orderNumber; @ExcelProperty({ 
   "一级","二三四级"}) private String ceshi; @ExcelProperty({ 
   "一级","二级头", "三级头","四级"}) private String string; @ExcelProperty({ 
   "一级","二级头", "三级头","四级"}) private Date date; @ExcelProperty({ 
   "一级","二级头", "三级头","四级"}) private Double doubleData; / * 忽略这个字段 */ @ExcelIgnore private String ignore; } 

测试类

//多级输出excel @Test public void mergeWrite() { 
    //创建数据 List<DemoData> list = new ArrayList<DemoData>(); for (int i = 0; i < 10; i++) { 
    DemoData data = new DemoData(); data.setOrderNumber(i); data.setCeshi("测试"); data.setString("测试" + i); data.setDate(new Date()); data.setDoubleData(0.820); list.add(data); } //文件名 String fileName = System.currentTimeMillis()+".xlsx"; // 每隔2行会合并 把eachColumn 设置成 3 也就是我们数据的长度，所以就第一列会合并。当然其他合并策略也可以自己写 LoopMergeStrategy loopMergeStrategy = new LoopMergeStrategy(2, 1); // 这里 需要指定写用哪个class去写，然后写到第一个sheet，名字为模板 然后文件流会自动关闭 EasyExcel.write(fileName, DemoData.class).registerWriteHandler(loopMergeStrategy).sheet("合并单元格") .doWrite(list); } 

new LoopMergeStrategy(2, 1); 2代表合并2行，1是索引 ，从第二个字段开始合并 序号字段不合并。

web导出下载文件

import com.alibaba.excel.EasyExcel; import com.alibaba.excel.write.merge.LoopMergeStrategy; import com.alibaba.excel.write.metadata.style.WriteCellStyle; import com.alibaba.excel.write.style.HorizontalCellStyleStrategy; import com.molomessage.message.excel.entity.DemoData; import org.apache.poi.ss.usermodel.HorizontalAlignment; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.util.ArrayList; import java.util.Date; import java.util.List; @RestController @RequestMapping("/export") public class ExportExcelController { 
    //使用easyExcel导出 @GetMapping("/test") public void easyExcelExport(HttpServletResponse response){ 
    try { 
    //创建数据 List<DemoData> list = new ArrayList<DemoData>(); for (int i = 0; i < 10; i++) { 
    DemoData data = new DemoData(); data.setOrderNumber(i); data.setCeshi("测试"); data.setString("测试" + i); data.setDate(new Date()); data.setDoubleData(0.820); list.add(data); } WriteCellStyle headWriteCellStyle = new WriteCellStyle(); //设置头居中 headWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.CENTER); //内容策略 WriteCellStyle contentWriteCellStyle = new WriteCellStyle(); //设置 水平居中 contentWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.LEFT); HorizontalCellStyleStrategy horizontalCellStyleStrategy = new HorizontalCellStyleStrategy(headWriteCellStyle, contentWriteCellStyle); response.setContentType("application/vnd.ms-excel;charset=utf-8"); //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easyexcel没有关系 String fileName = System.currentTimeMillis()+".xlsx"; // 每隔2行会合并 把eachColumn 设置成 3 也就是我们数据的长度，所以就第一列会合并。当然其他合并策略也可以自己写 LoopMergeStrategy loopMergeStrategy = new LoopMergeStrategy(2, 1); response.setHeader("Content-disposition", "attachment;filename=" + fileName + ".xls"); // 这里需要设置不关闭流 EasyExcel.write(response.getOutputStream(), DemoData.class).autoCloseStream(Boolean.FALSE).registerWriteHandler(horizontalCellStyleStrategy).sheet("用户信息表").doWrite(list); } catch (IOException e) { 
    e.printStackTrace(); } } }