【JAVA下载excel工具类】

SpringBoot 整合java下载excel

前几天逛吧的时候发现了一个很好的下载功能，代码非常的少，推荐使用。 下面我们就来看看吧

导入maven仓库

<dependency>
            <groupId>com.github.liaochong</groupId>
            <artifactId>myexcel</artifactId>
            <version>3.3.0.GA</version>
        </dependency>

创建excel下载工具类

package com.hjy.mall.common.util;


import com.github.liaochong.myexcel.core.DefaultStreamExcelBuilder;
import com.github.liaochong.myexcel.utils.AttachmentExportUtil;
import com.hjy.mall.common.api.ResultCode;
import com.hjy.mall.common.exception.ApiException;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executors;

public class StreamExport {
          
   

    /**导出表格最大容量*/
    public static final Integer EXCEL_MAX_CAPACITY = 60_000;

    public static void flowPattern(HttpServletResponse response, Class clazz, List list, String fileName) {
          
   
        //long start = System.currentTimeMillis();
        try (DefaultStreamExcelBuilder streamExcelBuilder = DefaultStreamExcelBuilder
                .of(clazz)
                .threadPool(Executors.newFixedThreadPool(10))
                .capacity(EXCEL_MAX_CAPACITY)
                .start()) {
          
   
            // 多线程异步获取数据并追加至excel，join等待线程执行完成
            List<CompletableFuture> futures = new ArrayList<>();

                CompletableFuture future = CompletableFuture.runAsync(() -> {
          
   
                    List dataList = list;
                    // 数据追加
                    streamExcelBuilder.append(dataList);
                });

                futures.add(future);
            futures.forEach(CompletableFuture::join);
            // 最终构建
            Path zip = streamExcelBuilder.buildAsZip(fileName);
            AttachmentExportUtil.export(zip,fileName+".zip",response);
        } catch (IOException e) {
          
   
            // e.printStackTrace();
           throw new ApiException(ResultCode.FAILED);
        }

    }
}

编写接口示范

@RequestMapping(value = "/excel", method = RequestMethod.GET)
    @PreAuthorize("hasAnyAuthority(/finance/financeExcel)")
    public void financeExcel(){
          
   
    //用户列表
     List<UserDto> userList= UserService.getUserInfo();
     //调用工具类
     StreamExport.flowPattern(((ServletRequestAttributes) RequestContextHolder.getRequestAttributes())
                .getResponse(), UserDto.class,userList , "用户列表"+ DateFormatter.HHmmssSSS());
    }

到这里就结束了，简单，方便。