easypoi可以很方便的导出excel，但是涉及到图片的导出，还是有点麻烦的，尤其是获取网络图片然后导出excel
思路是：获取网络图片为二进制字节数组，然后导出excel

引入pom

<!-- easypoi -->
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-base</artifactId>
    <version>3.0.3</version>
</dependency>
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-web</artifactId>
    <version>3.0.3</version>
</dependency>
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-annotation</artifactId>
    <version>3.0.3</version>
</dependency>

导出实体：

package com.cec.park.module.dto;

import cn.afterturn.easypoi.excel.annotation.Excel;

/**
 * @author zhy
 * @title: TestDto
 * @projectName car_park
 * @description: TODO
 * @date 2019/10/2218:52
 */
public class TestDto {

    @Excel(name = "名称",width = 40)
    private String name;
    @Excel(name = "公司LOGO", type = 2 ,width = 40 , height = 20,imageType = 2)
    private byte[] companyLogo;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public byte[] getCompanyLogo() {
        return companyLogo;
    }

    public void setCompanyLogo(byte[] companyLogo) {
        this.companyLogo = companyLogo;
    }
}

@Excel(name = "公司LOGO", type = 2 ,width = 40 , height = 20,imageType = 2)
private byte[] companyLogo;

type = 2 代表的是导出图片，imageType = 2 代表的是将二进制数组转换成图片。companyLogo是二进制数组

如果是本地图片写法是
@Excel(name = "公司LOGO", type = 2 ,width = 40 , height = 20,imageType = 1)
private String companyLogo;
companyLogo是本地图片路径

获取网络图片为二进制数组的工具类

package com.cec.park.module.utils;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * @author zhy
 * @title: HttpClientUtil
 * @projectName car_park
 * @description: http连接工具类
 * @date 2019/10/2219:23
 */
public class HttpClientUtil {


    /**
     * @param [strUrl]
     * @return byte[]
     * @throws
     * @description: 获取网络图片转成字节流
     * @author zhy
     * @date 2019/10/23 8:59
     */
    public static byte[] getImageFromNetByUrl(String strUrl) {
        if (!isURL(strUrl)){
            return null;
        }
        try {
            URL url = new URL(strUrl);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            conn.setConnectTimeout(2 * 1000);
            InputStream inStream = conn.getInputStream();// 通过输入流获取图片数据
            byte[] btImg = readInputStream(inStream);// 得到图片的二进制数据
            return btImg;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 从输入流中获取字节流数据
     *
     * @param inStream 输入流
     * @return
     * @throws Exception
     */
    public static byte[] readInputStream(InputStream inStream) throws Exception {
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[10240];
        int len = 0;
        while ((len = inStream.read(buffer)) != -1) {
            outStream.write(buffer, 0, len);
        }
        inStream.close();
        return outStream.toByteArray();
    }

    public static boolean isURL(String str) {
        str = str.toLowerCase();
        String regex = "^((https|http|ftp|rtsp|mms)?://)"
                + "?(([0-9a-z_!~*'().&=+$%-]+: )?[0-9a-z_!~*'().&=+$%-]+@)?"
                + "(([0-9]{1,3}\\.){3}[0-9]{1,3}"
                + "|"
                + "([0-9a-z_!~*'()-]+\\.)*"
                + "([0-9a-z][0-9a-z-]{0,61})?[0-9a-z]\\."
                + "[a-z]{2,6})"
                + "(:[0-9]{1,5})?"
                + "((/?)|"
                + "(/[0-9a-z_!~*'().;?:@&=+$,%#-]+)+/?)$";
        return str.matches(regex);
    }


}

导出方法

    @GetMapping("/exportTestExcel")
    public void exportTestExcel(HttpServletResponse response){
        List<TestDto> dtos = new ArrayList<>();
        TestDto testDto = new TestDto();
        testDto.setName("第一张");
        byte[] imageFromNetByUrl = HttpClientUtil.getImageFromNetByUrl("https://pics0.baidu.com/feed/79f0f736afc37931275e6caaa786164042a911c2.jpeg?token=5dfe37d5ec1518a0348aa50037f91067&s=3F654980420128EE65994110030050CA");
        testDto.setCompanyLogo(imageFromNetByUrl);
        dtos.add(testDto);
        String fileName = "测试.xls";
        Workbook workbook = ExcelExportUtil.exportExcel(new ExportParams("测试导出图片", "测试导出图片"), TestDto.class, dtos);
        ServletOutputStream outputStream = null;
        try {
            outputStream = response.getOutputStream();
            response.setCharacterEncoding("UTF-8");
            response.setHeader("content-Type", "application/vnd.ms-excel");
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
            workbook.write(outputStream);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }finally {
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }