网站开发试题济南疫情最新情况

需求

在服务端提前准备好Word模板文件，并在用户请求接口时服务端动态获取图片。数据等信息插入到模板当中，然后返回包含数据信息的Word文件流。

一、准备模板文件

在需要插入图片的地方使用：{{@参数名}}，文本信息使用：{{参数名}}，进行占位，占位格式将会被保留，经过处理后格式不变

将准备好的模板文件放在resources目录下

二、引入Poi-tl、Apache POI依赖

poi-tl（poi template language）是Word模板引擎，基于Apache POI，提供更友好的API，使用起来更加简单
版本对应关系参考Poi-tl官网

<!--    替换自己使用的版本    -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>4.1.*</version>
</dependency>
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>4.1.*</version>
</dependency>
<!--    Word模板引擎    -->
<dependency><groupId>com.deepoove</groupId><artifactId>poi-tl</artifactId><version>1.7.*</version>
</dependency>

三、创建实体类（用于保存向Word中写入的数据）

参数名必须同Word模板中的参数名称保持一致

import com.deepoove.poi.data.PictureRenderData;@Data
public class DownloadDate {//图片使用PictureRenderData类型private PictureRenderData image;private String name;private String a;private String b;private String c;private String d;private String e;private String f;private String g;private String h;private String i;
}

四、实现Service接口

public interface DownloadService {void download(HttpServletResponse response, DownloadDTO downloadDTO) throws IOException;
}

@Service
@Slf4j
public class DownloadServiceImpl implements DownloadService {@Resource//远程调用服务private FeignService feignService;@Overridepublic void download(HttpServletResponse response, DownloadDTO downloadDTO) throws IOException {BufferedImage、字节数组），Base64可以转字节数组后使用//通过调用其它接口获取待写入的数据信息WordData wordData = feignService.getData(downloadDTO);/** * 图片可以是多种格式------------------------* 图片路径：PictureRenderData(int width, int height, String path)* File：PictureRenderData(int width, int height, File picture)* InputStream：PictureRenderData(int width, int height, String format, InputStream input)* BufferedImage：PictureRenderData(int width, int height, String format, BufferedImage image)* 字节数组：PictureRenderData(int width, int height, String format, byte[] data)* Base64可以转字节数组后使用*///以Base64为例，先获取图片的Base64编码（wordData.getImg是原始图片Base64数据）String base64ImageData = wordData.getImg.substring(data.indexOf(",") + 1);//获取图片类型String format = getBase64Type(base64ImageData);// 将base64数据转为字节数组byte[] imageBytes = Base64.getDecoder().decode(base64ImageData);// 将字节数组包装成PictureRenderDataPictureRenderData pictureRenderData = new PictureRenderData(690,530,format,imageBytes);//待写入Word的数据DownloadDate downloadDate = new DownloadDate();//图片信息downloadDate.setImage(pictureRenderData);//其它信息downloadDate.setName(wordData.getName());//...XWPFTemplate template = null;BufferedOutputStream bufferedOutputStream = null;ServletOutputStream outputStream = null;try {/** * 该方法会导致在部分环境中资源找不到的情况，不推荐使用*///获得resource路径+模板路径//String path = Objects.requireNonNull(Thread.currentThread().getContextClassLoader().getResource("")).getPath() + "word/template.docx";// 读取Word模板//FileInputStream templateInputStream = new FileInputStream(path);// 模板绑定数据//template = XWPFTemplate.compile(templateInputStream).render(imageDownloadDate);// 从资源中加载Word模板try (InputStream templateInputStream = getClass().getClassLoader().getResourceAsStream("word/template.docx")) {if (templateInputStream != null) {// 模板绑定数据template = XWPFTemplate.compile(templateInputStream).render(imageDownloadDate);} else {// 处理模板资源未找到的情况log.error("Word模板资源未找到");response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);return;}}//文件名String encodedFileName = URLEncoder.encode(System.currentTimeMillis()+"", "utf-8");//设置响应信息response.setHeader("Content-Disposition", "attachment;filename=" + encodedFileName + ".docx");response.setContentType("application/vnd.openxmlformats-officedocument.wordprocessingml.document");response.setCharacterEncoding("utf-8");outputStream = response.getOutputStream();bufferedOutputStream = new BufferedOutputStream(outputStream);template.write(bufferedOutputStream);//清空流bufferedOutputStream.flush();outputStream.flush();} catch (Exception e) {log.info(e.getMessage());response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);} finally {//关闭资源PoitlIOUtils.closeQuietlyMulti(template, bufferedOutputStream, outputStream);}}//根据base64编码获取图片格式信息private String getBase64Type(String base64) {byte[] b = Base64.getDecoder().decode(base64);String type = ".png";if (0x424D == ((b[0] & 0xff) << 8 | (b[1] & 0xff))) {type = ".bmp";} else if (0x8950 == ((b[0] & 0xff) << 8 | (b[1] & 0xff))) {type = ".png";} else if (0xFFD8 == ((b[0] & 0xff) << 8 | (b[1] & 0xff))) {type = ".jpg";} else if (0x49492A00 == ((b[0] & 0xff) << 24 | (b[1] & 0xff) << 16 | (b[2] & 0xff) << 8 | (b[3] & 0xff))) {type = ".tif";}return type;}}

五、Controller层实现

@RestController
@RequestMapping("/test")
@Api(tags = "获取商品图片")
public class GetImageController {@ResourceDownloadService downloadService;@PostMapping("/download")@ApiOperation(value = "下载Word")void download(HttpServletResponse response,@RequestBody DownloadDTO downloadDTO) throws IOException {//鉴权或其它处理//....downloadService.download(response,downloadDTO);}}