EasyExcel_通过模板导出(多sheet、列表、图片)

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前言

产品今天提了个需求，大概是这样的，来，请看大屏幕。。。额。。。搞错了，重来！来，请看需求
设计到多sheet、列表、图片的模板导出，先看成品

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一、EasyExcel是什么？

EasyExcel是一个基于Java的、快速、简洁、解决大文件内存溢出的Excel处理工具。
他能让你在不用考虑性能、内存的等因素的情况下，快速完成Excel的读、写等功能。
详细介绍见官网：EasyExcel官网

二、模板样式调整

三、使用步骤

1.引入jar包

	<dependency>
		<groupId>com.alibaba</groupId>
		<artifactId>easyexcel</artifactId>
		<version>3.1.1</version>
	</dependency>

2.方法示例

2.1 Controller：

import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.net.URLEncoder;
/**
 1. <p>
 2. 可靠性测试委托单 前端控制器
 3. </p>
 4.  5. @author zs
 6. @since 2024-06-21
 */
@RestController
@Api(tags = "可靠性测试委托单")
@Validated
@Slf4j
@RequestMapping("/reliabitestEntrust")
public class ReliabitestEntrustController {
   
	@Resource
    private IReliabitestEntrustService entrustService;


	@ApiOperation(value = "可靠性测试委托单-下载报告")
    @GetMapping("/downEntrustReport")
    public void downEntrustReport(HttpServletResponse response, @RequestParam("id") @NotNull(message = "id不能为空") Long id) {
   
        try {
   
            ByteArrayOutputStream oos = new ByteArrayOutputStream();
            String fileName = entrustService.downEntrustReport(oos, id);
            response.setHeader("Content-Disposition", "attachment;filename*=" + URLEncoder.encode(fileName, "UTF-8"));
            oos.writeTo(response.getOutputStream());
            oos.flush();
            oos.close();
        } catch (Exception e) {
   
            log.error("可靠性测试委托单-下载报告出错了：{}", e);
            response.reset();
            response.setContentType("application/json");
            response.setCharacterEncoding("utf-8");
            try {
   
                ResponseBean resp = ResponseBean.buildFail(CodeEnums.FAIL.getCode(), e.getMessage());
                response.getWriter().println(JSONObject.toJSONString(resp));
            } catch (Exception e1) {
   
                log.error("可靠性测试委托单-下载报告,出错了：{}", e1);
            }
        }
    }
}

2.2 Service：

/**
 * <p>
 * 可靠性测试委托单 服务类
 * </p>
 *
 * @author zs
 * @since 2024-06-21
 */
public interface IReliabitestEntrustService extends IService<ReliabitestEntrust> {
    
    /**
     * 功能: 下载委托单报告
     * 调用时机: 点击下载报告按钮
     * 注意事项: 参数必传
     *
     * @return
     * @author zs
     * @date 2024/6/27
     */
    String downEntrustReport(OutputStream outputStream, Long id) throws Exception;


}

2.3 ServiceImpl:

 /**
     * 功能: 下载委托单报告
     * 调用时机: 点击下载报告按钮
     * 注意事项: 参数必传
     *
     * @return
     * @author zs
     * @date 2024/6/27
     */
    @Override
    public String downEntrustReport(OutputStream outputStream, Long id) throws Exception {
   
        // Step 1: 获取委托单主表、详情、问题点与改善、委托单配置
        CompletableFuture<ReliabitestEntrust> entrustFuture = CompletableFuture.supplyAsync(() -> this.getById(id));
        CompletableFuture<List<ReliabitestEntrustDetail>> detailFuture = CompletableFuture.supplyAsync(() -> entrustDetailService.queryByEntrustId(id));
        CompletableFuture<List<ReliabitestEntrustQuestion>> questionFuture = CompletableFuture.supplyAsync(() -> entrustQuestionService.queryByEntrustId(id));
        // 获取config配置
        ResponseBean<List<GetConfigListByTypeResp>> response = basicsClient.getConfigsByType(47);
        CheckException.checkThrowException(() -> !response.isSuccess() || CollectionUtil.isEmpty(response.getData()), "委托单配置为空,请检查配置!!!");
        List<GetConfigListByTypeResp> configList = response.getData();

        // 试验项目 code+名称
        Map<String, String> codeAndNameMap = configList.stream().collect(Collectors.toMap(e -> e.getCode(), a -> a.getName(), (k1, k2) -> k1));

        // 子集
        List<GetConfigListByTypeResp> childrenList = configList.stream().map(GetConfigListByTypeResp::getChildrenList)
                .flatMap(List::stream).collect(Collectors.toList());
        Map<String, String> childMap = childrenList.stream().collect(Collectors.toMap(e -> e.getCode(), a -> a.getName(), (k1, k2) -> k1));

        // Step 2: 组装模板数据
        ReliabitestEntrust entrust = entrustFuture.get();

        // 主信息
        DownEntrustReportDTO dto = new DownEntrustReportDTO();
        if (ObjectUtil.isNotNull(entrust))