libreoffice在Windows和Linux环境的安装和结合Springboot使用教程

前言：

在公司做开发时，遇到一个需求，要求上传的文件有图片，也有word和pdf。预览信息时，既要求能水印展示出来，又要求能大图水印预览。思索许久，我决定采取全部打水印然后转成图片Base64，但是后面突然发现word不能直接转为图片，强制转换会有内容丢失，于是我打算先把word转为pdf，然后再把pdf转为图片Base64，思路堪称完美。

思路有了，那该选什么工具好呢？网上的教程参差不齐，有的工具也能用，但是转出来的效果不尽人意，在寻找许久后我选择了document4j，这工具在转换方面堪称完美，但美中不足的是只能在Windows上使用，最后我选择了libreoffice。

libreoffice既兼容Windows，同时又兼容Linux，转换出来的效果也不错，于是我的工具问题也就迎刃而解了。

环境：

IntelliJ IDEA 2024.1.4

Linux服务器

Windows笔记本

Oracle数据库（Mysql数据也行，我这里测试用的Mysql）

LibreOffice 24.2.4 下载地址：下载 LibreOffice | LibreOffice 简体中文官方网站 - 自由免费的办公套件

1.安装教程：

我们需要下载两个LibreOffice 24.2.4，一个是Windows的，一个是Linux的。另外下载的话选择国内镜像下载，比较快：

Window下载完成后安装在D盘即可（选择），安装没有特别需要注意的，安装完自己记得路径就行。对于Linux安装，安装如下：

1.1解压压缩包

上传到linux指定目录下或者用wget直接下载到linux指定目录下后（我上传到的是/opt目录下），使用下面命令解压：

cd /opt
tar -xvf LibreOffice_24.2.4_Linux_x86-64_rpm.tar.gz

1.2安装libreoffice

执行下面命令开始安装，等待安装完成即可：

sudo yum install ./LibreOffice_24.2.4_Linux_x86-64_rpm/RPMS/*.rpm

1.3启动libreoffice

Windows的话cmd执行下面命令启动，其中D:Program FilesLibreOffice就是安装的路径：

D:Program FilesLibreOfficeprogramsoffice.exe --headless --invisible --nologo --nodefault --nofirststartwizard --accept="socket,host=127.0.0.1,port=8100;urp;"

Linux的话执行下面命令启动，同样的/opt/libreoffice24.2就是安装的路径：

/opt/libreoffice24.2/program/soffice --headless --invisible --nologo --nodefault --nofirststartwizard --accept="socket,host=127.0.0.1,port=8100;urp;"

Linux的话还可以使用docker部署，这样的话就可以不用安装并启动得那么麻烦，使用的镜像是libreoffice/online，但是要把这个安装的libreoffice映射出来，我这里就不详细介绍了，感兴趣的可以自己去试一试。

到此，Windows的安装启动就结束了，但是Linux还没有结束，因为Linux缺少中文字体的缘故，导致转出来的中文会是如下的效果：

为此，我们要给Linux装上中文字体：

1.4Linux安装中文字体

首先安装fontconfig：

yum -y install fontconfig

进入/usr/share目录下，执行ls会发现这两个目录，则说明安装成功：

cd /usr/share
ls

接着，打开这个fonts文件夹，新建一个叫chinese文件夹：

cd fonts
mkdir chinese

然后将Windows系统的字体文件全部拷进去（这里直接复制是不允许的，需要复制C:Windows下的Fonts目录到桌面，然后再从桌面双击进入Fonts文件夹，Ctrl+A全选，上传到服务器的这个chinese目录下）：

接着给这个目录赋予权限，执行命令：

chmod -R 755 /usr/share/fonts/chinese

安装ttmkfdir，编辑配置文件，执行命令：

yum -y install ttmkfdir
ttmkfdir -e /usr/share/X11/fonts/encodings/encodings.dir
vi /etc/fonts/fonts.conf

在Font directory list配置项下，把这个中文字体目录加进去，添加如下代码：

<dir>/usr/share/fonts/chinese</dir>

保存退出后，执行下面命令刷新一下缓存

fc-cache

到此，中文字体安装完成。转出的效果也变成了如下图，中文字体也能正常显示了：

2.Springboot集成libreoffice

环境安装好了，解下来，我们就开始写代码了。

2.1引入pom依赖

首先创建完Springboot项目后，安装必要的依赖，其中重点就是jodconverter-spring-boot-starter和jodconverter-local，其他的看需要引入：

        <!--office转换工具--><dependency><groupId>org.jodconverter</groupId><artifactId>jodconverter-spring-boot-starter</artifactId><version>4.4.7</version></dependency><dependency><groupId>org.jodconverter</groupId><artifactId>jodconverter-local</artifactId><version>4.4.7</version></dependency><!--pdfbox--><dependency><groupId>org.apache.pdfbox</groupId><artifactId>pdfbox</artifactId><version>2.0.24</version></dependency><!--hutool--><dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>5.8.25</version></dependency><!--Apache Commons--><dependency><groupId>org.apache.commons</groupId><artifactId>commons-collections4</artifactId><version>4.4</version></dependency><dependency><groupId>commons-io</groupId><artifactId>commons-io</artifactId><version>2.16.1</version></dependency><dependency><groupId>org.apache.commons</groupId><artifactId>commons-lang3</artifactId><version>3.12.0</version></dependency><!--Apache Poi--><dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>5.2.5</version></dependency><!--itextpdf--><dependency><groupId>com.itextpdf</groupId><artifactId>itextpdf</artifactId><version>5.5.13.4</version></dependency>

2.2修改yaml配置文件

修改application.yaml，添加如下配置：

spring:profiles:active: local# 共享配置
jodconverter:local:enabled: trueportNumbers: 8100maxTasksPerProcess: 100taskQueueTimeout: 60file:path:windows: 'D:/temp/file'linux: '/file'---
spring:config:activate:on-profile: local
jodconverter:local:officeHome: 'D:Program FilesLibreOffice'
---
spring:config:activate:on-profile: server
jodconverter:local:officeHome: '/opt/libreoffice24.2'

其中我用spring: profiles: active: 来区分是Windows启动的项目还是Linux，若是Windows则改为local，若是Linux的话改成server即可；

file:path:是文件上传后保存的目录。若是Linux环境确保启动该项目的用户对该目录有足够的读写权限，否则上传文件会报错500。

2.3control层代码

FileControl.java完整代码如下：

package com.example.testdemo.test.control;import com.example.testdemo.test.model.DownloadFile;
import com.example.testdemo.test.service.FileService;
import com.example.testdemo.test.utils.Result;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;/*** 项目名称: testDemo* 作者: zhaojs* 创建日期: 2024年07月04日* 文件说明: 文件控制层*/
@RestController
public class FileControl {/*** 文件服务*/@Resourceprivate FileService fileService;/*** 文件上传* @param files* @return*/@PostMapping("/file/upload")public Result uploadFile(@RequestParam("files") MultipartFile[] files) {return fileService.uploadFile(files);}/*** 获取文件列表* @param ids* @return*/@GetMapping("/file/getFile/{ids}")public Result getFile(@PathVariable("ids") String ids) {return Result.success(fileService.getFile(ids));}/*** 附件转为图片的base64编码* 支持附件类型：doc、docx、pdf、png、jpeg* @param downloadFile*/@PostMapping("/file/switchAttachment/imageBase64")public Result switchAttachmentImageBase64(@RequestBody DownloadFile downloadFile) {return fileService.switchAttachmentImageBase64(downloadFile);}
}

2.4service层代码

FileService.java完整代码如下：

package com.example.testdemo.test.service;import com.example.testdemo.test.model.Attachment;
import com.example.testdemo.test.model.DownloadFile;
import com.example.testdemo.test.utils.Result;
import org.springframework.web.multipart.MultipartFile;import javax.servlet.http.HttpServletResponse;
import java.util.List;/*** 项目名称: testDemo* 创建日期: 2024年07月04日* @author zhaojs* 文件说明: 见类描述*/
public interface FileService {/*** 上传文件* @param files* @return*/Result uploadFile(MultipartFile[] files);/*** 获取文件列表* @param ids* @return*/List<Attachment> getFile(String ids);/*** 附件转为图片的base64编码* @param downloadFile* @return*/Result switchAttachmentImageBase64(DownloadFile downloadFile);
}

FileServiceImpl.java完整代码如下：

package com.example.testdemo.test.service.Impl;import com.example.testdemo.test.dao.AttachmentDao;
import com.example.testdemo.test.model.Attachment;
import com.example.testdemo.test.model.DownloadFile;
import com.example.testdemo.test.service.FileService;
import com.example.testdemo.test.utils.Result;
import com.example.testdemo.test.utils.WordWaterMarker;
import com.itextpdf.text.Element;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfGState;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfStamper;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.commons.collections4.MapUtils;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.ImageType;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.apache.poi.xwpf.usermodel.XWPFDocument;
import org.jodconverter.core.DocumentConverter;
import org.jodconverter.core.document.DefaultDocumentFormatRegistry;
import org.jodconverter.core.document.DocumentFormat;
import org.jodconverter.core.office.OfficeException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.io.FileSystemResource;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;import javax.annotation.Resource;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Base64;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentSkipListSet;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;@Service
public class FileServiceImpl implements FileService {/*** Windows文件路径*/@Value("${file.path.windows}")private String filePathWindows;/*** Linux文件路径*/@Value("${file.path.linux}")private String filePathLinux;/*** 文档转换器*/@Resourceprivate DocumentConverter documentConverter;/*** 附件表Dao*/@Resourceprivate AttachmentDao attachmentDao;/*** 日期时间格式*/private static final DateTimeFormatter DATE_TIME_FORMATTER = DateTimeFormatter.ofPattern("yyyyMMddHHmmssSSS");/*** 并发处理任务的数量*/private static final int MAX_CONCURRENT_TASKS = 5;/*** 日志*/private static final Logger logger = LoggerFactory.getLogger(FileServiceImpl.class);/*** 上传文件** @param files* @return*/@Overridepublic Result uploadFile(MultipartFile[] files) {try {// 遍历文件数组并处理每个文件for (MultipartFile file : files) {if (! file.isEmpty()) {// 处理文件名String originalFilename = file.getOriginalFilename();String extension = FilenameUtils.getExtension(originalFilename);String uniqueFilename = UUID.randomUUID().toString() + (extension != null && ! extension.isEmpty() ? "." + extension : "");// 获取当前日期并格式化为年月目录格式LocalDate now = LocalDate.now();DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy/MM");String yearMonthDir = now.format(formatter);// 指定保存的根目录，对于Windows可以是D盘的某个路径，对于Linux通常是/home/user或特定的目录String rootDir = System.getProperty("os.name").toLowerCase().startsWith("win") ? filePathWindows : filePathLinux;// 构建保存文件的完整路径，使用Paths.get()自动处理路径分隔符Path directoryPath = Paths.get(rootDir, yearMonthDir);// 确保目录存在Files.createDirectories(directoryPath);// 文件保存路径Path filePath = directoryPath.resolve(uniqueFilename);// 将文件输入流中的数据复制到目标路径，如果目标文件已存在，则覆盖原有文件Files.copy(file.getInputStream(), filePath, StandardCopyOption.REPLACE_EXISTING);// 插入附件表Attachment attachment = new Attachment();attachment.setAttachmentId(UUID.randomUUID().toString());attachment.setFileId(uniqueFilename);attachment.setFileName(originalFilename);attachment.setFileType(file.getContentType());attachment.setFileSize(Double.valueOf(file.getSize()));attachment.setFilePath(filePath.toString());attachment.setCreateTime(LocalDateTime.now());attachmentDao.insert(attachment);} else {return Result.fail("文件为空");}}return Result.success("文件上传成功");} catch (IOException e) {return Result.fail("文件上传失败");}}/*** 获取文件列表** @param ids* @return*/@Overridepublic List<Attachment> getFile(String ids) {if (StringUtils.isNotBlank(ids)) {String[] attachmentIds = ids.split(",");List<Attachment> attachmentList = attachmentDao.selectBatchIds(Arrays.asList(attachmentIds));return attachmentList;}return null;}/*** 附件转为图片的base64编码** @param downloadFile* @return*/@Overridepublic Result switchAttachmentImageBase64(DownloadFile downloadFile) {List<Map<String, String>> fileList = new ArrayList<>();List<Attachment> attachmentList = getFile(downloadFile.getAttachmentIds());attachmentList.forEach(attachment -> {Map<String, String> map = new HashMap<>();map.put("fileName", attachment.getFileName());map.put("filePath", attachment.getFilePath());fileList.add(map);});//附件归类List<String> imageFilePathList = new ArrayList<>();List<String> pdfFilePathList = new ArrayList<>();List<String> wordFilePathList = new ArrayList<>();fileList.forEach(map -> {// 附件名称String fileName = MapUtils.getString(map, "fileName");// 判断附件类型String filePath = MapUtils.getString(map, "filePath");if (fileName.endsWith(".jpg") || fileName.endsWith(".jpeg") || fileName.endsWith(".png")) {imageFilePathList.add(filePath);} else if (fileName.endsWith(".pdf")) {pdfFilePathList.add(filePath);} else if (fileName.endsWith(".doc") || fileName.endsWith(".docx")) {wordFilePathList.add(filePath);}});List<String> imageBase64List = new ArrayList<>();//先把word转为图片base64编码if (CollectionUtils.isNotEmpty(wordFilePathList)) {List<String> imageBase64 = wordFileToImageBase64(wordFilePathList, downloadFile.getWatermarkText());if (imageBase64 != null && ! imageBase64.isEmpty()) {imageBase64List.addAll(imageBase64);}}//再把pdf转为图片base64编码if (CollectionUtils.isNotEmpty(pdfFilePathList)) {List<String> imageBase64 = pdfFileToImageBase64(pdfFilePathList, downloadFile.getWatermarkText());if (imageBase64 != null && ! imageBase64.isEmpty()) {imageBase64List.addAll(imageBase64);}}//最后把图片直接转为base64编码if (CollectionUtils.isNotEmpty(imageFilePathList)) {List<String> imageBase64 = imageFileToBase64(imageFilePathList, downloadFile.getWatermarkText());if (imageBase64 != null && ! imageBase64.isEmpty()) {imageBase64List.addAll(imageBase64);}}return Result.success(imageBase64List);}/*** word转为图片base64编码** @param wordFilePathList* @param watermarkText* @return*/public List<String> wordFileToImageBase64(List<String> wordFilePathList, String watermarkText) {List<String> imageBase64List = new ArrayList<>();ExecutorService executor = Executors.newFixedThreadPool(MAX_CONCURRENT_TASKS);try {List<Future<List<String>>> futures = new ArrayList<>();// 首先，将Word文件转换为PDF字节流，并为每个字节流创建一个转换任务for (String filePath : wordFilePathList) {// 将Word转换为PDF字节流ByteArrayOutputStream pdfByteStream = wordToPdf(filePath);// 将PDF字节流转换为图片Base64Callable<List<String>> task = () -> pdfByteToImageBase64Single(pdfByteStream.toByteArray(), watermarkText);futures.add(executor.submit(task));}// 收集所有任务的结果for (Future<List<String>> future : futures) {try {// 合并每个任务返回的Base64编码图像字符串列表imageBase64List.addAll(future.get());} catch (InterruptedException | ExecutionException e) {Thread.currentThread().interrupt();logger.error("处理PDF字节流时发生错误", e);}}} finally {executor.shutdown();try {if (! executor.awaitTermination(60, TimeUnit.SECONDS)) {executor.shutdownNow();}} catch (InterruptedException e) {executor.shutdownNow();Thread.currentThread().interrupt();logger.error("关闭线程池时发生中断", e);}}return imageBase64List;}/*** word转pdf** @param wordFilePath* @return* @throws Exception*/public ByteArrayOutputStream wordToPdf(String wordFilePath) {ByteArrayOutputStream pdfOutputStream = new ByteArrayOutputStream();try (InputStream docxInputStream = new FileInputStream(wordFilePath)) {DocumentFormat type = "docx".equals(getFileType(new File(wordFilePath))) ? DefaultDocumentFormatRegistry.DOCX : DefaultDocumentFormatRegistry.DOC;documentConverter.convert(docxInputStream).as(type).to(pdfOutputStream).as(DefaultDocumentFormatRegistry.PDF).execute();} catch (IOException | OfficeException e) {logger.error("转换Word文件为PDF时发生错误", e);throw new RuntimeException(e);}return pdfOutputStream;}/*** pdfBytes转图片Base64（单个字节流处理）** @param pdfBytes* @param watermarkText* @return*/private List<String> pdfByteToImageBase64Single(byte[] pdfBytes, String watermarkText) {List<String> imageBase64List = new ArrayList<>();try (PDDocument document = PDDocument.load(pdfBytes)) {PDFRenderer pdfRenderer = new PDFRenderer(document);for (int pageIndex = 0; pageIndex < document.getNumberOfPages(); pageIndex++) {BufferedImage image = pdfRenderer.renderImageWithDPI(pageIndex, 300, ImageType.RGB);ByteArrayOutputStream baos = new ByteArrayOutputStream();ImageIO.write(image, "png", baos);baos.flush();byte[] imageBytes = baos.toByteArray();baos.close();if (StringUtils.isNotBlank(watermarkText)) {try (InputStream watermarkedInputStream = addImageWaterMark(new ByteArrayInputStream(imageBytes), watermarkText)) {byte[] watermarkedBytes = watermarkedInputStream.readAllBytes();watermarkedInputStream.close();String format = "png";String fullEncodedImage = "data:image/" + format + ";base64," + Base64.getEncoder().encodeToString(watermarkedBytes);imageBase64List.add(fullEncodedImage);} catch (IOException e) {logger.error("添加水印时发生错误", e);}} else {String format = "png";String fullEncodedImage = "data:image/" + format + ";base64," + Base64.getEncoder().encodeToString(imageBytes);imageBase64List.add(fullEncodedImage);}}} catch (IOException e) {logger.error("处理PDF字节流时发生错误", e);}return imageBase64List;}/*** pdf转图片Base64** @param pdfFilePathList* @param watermarkText* @return*/public List<String> pdfFileToImageBase64(List<String> pdfFilePathList, String watermarkText) {List<String> imageBase64List = new ArrayList<>();ExecutorService executor = Executors.newFixedThreadPool(MAX_CONCURRENT_TASKS);try {// 提交任务到线程池List<Future<List<String>>> futures = new ArrayList<>();for (String filePath : pdfFilePathList) {Callable<List<String>> task = () -> convertSinglePdfToImageBase64(filePath, watermarkText);futures.add(executor.submit(task));}// 收集所有任务的结果for (Future<List<String>> future : futures) {try {// 获取并合并每个任务的结果imageBase64List.addAll(future.get());} catch (InterruptedException | ExecutionException e) {Thread.currentThread().interrupt();logger.error("处理PDF文件时发生错误", e);}}} finally {executor.shutdown();try {if (! executor.awaitTermination(60, TimeUnit.SECONDS)) {executor.shutdownNow();}} catch (InterruptedException e) {executor.shutdownNow();Thread.currentThread().interrupt();logger.error("关闭线程池时发生中断", e);}}return imageBase64List;}/*** 单个PDF转图片Base64** @param filePath* @param watermarkText* @return*/private List<String> convertSinglePdfToImageBase64(String filePath, String watermarkText) {List<String> singleFileImageBase64List = new ArrayList<>();try (PDDocument document = PDDocument.load(new FileSystemResource(filePath).getFile())) {PDFRenderer pdfRenderer = new PDFRenderer(document);for (int pageIndex = 0; pageIndex < document.getNumberOfPages(); pageIndex++) {BufferedImage image = pdfRenderer.renderImageWithDPI(pageIndex, 300, ImageType.RGB);ByteArrayOutputStream baos = new ByteArrayOutputStream();ImageIO.write(image, "png", baos);baos.flush();byte[] imageBytes = baos.toByteArray();baos.close();if (StringUtils.isNotBlank(watermarkText)) {try (InputStream watermarkedInputStream = addImageWaterMark(new ByteArrayInputStream(imageBytes), watermarkText)) {byte[] watermarkedBytes = watermarkedInputStream.readAllBytes();String format = "png";String fullEncodedImage = "data:image/" + format + ";base64," + Base64.getEncoder().encodeToString(watermarkedBytes);singleFileImageBase64List.add(fullEncodedImage);} catch (IOException e) {logger.error("添加水印时发生错误", e);}} else {String format = "png";String fullEncodedImage = "data:image/" + format + ";base64," + Base64.getEncoder().encodeToString(imageBytes);singleFileImageBase64List.add(fullEncodedImage);}}} catch (IOException e) {logger.error("加载PDF文档时发生错误", e);}return singleFileImageBase64List;}/*** 图片转为base64编码** @param imageFilePathList* @param watermarkText* @return*/public List<String> imageFileToBase64(List<String> imageFilePathList, String watermarkText) {List<String> imageBase64List = new ArrayList<>();ExecutorService executor = Executors.newFixedThreadPool(MAX_CONCURRENT_TASKS);try {// 提交任务到线程池List<Future<String>> futures = imageFilePathList.stream().map(path -> executor.submit(() -> convertSingleImageToBase64(path, watermarkText))).collect(Collectors.toList());// 收集所有任务的结果for (Future<String> future : futures) {try {// 添加每个任务返回的Base64编码字符串imageBase64List.add(future.get());} catch (InterruptedException | ExecutionException e) {Thread.currentThread().interrupt();logger.error("处理图像文件时发生错误", e);}}} finally {executor.shutdown();try {if (! executor.awaitTermination(60, TimeUnit.SECONDS)) {executor.shutdownNow();}} catch (InterruptedException e) {executor.shutdownNow();Thread.currentThread().interrupt();logger.error("关闭线程池时发生中断", e);}}return imageBase64List;}/*** 单个图像文件转换为Base64字符串** @param imagePath     图像文件路径* @param watermarkText* @return Base64编码的字符串*/private String convertSingleImageToBase64(String imagePath, String watermarkText) {try {File file = new File(imagePath);InputStream originalInputStream = new FileInputStream(file);if (StringUtils.isNotBlank(watermarkText)) {try (InputStream watermarkedInputStream = addImageWaterMark(originalInputStream, watermarkText)) {byte[] bytes = watermarkedInputStream.readAllBytes();String format = getFileExtension(file.getName()).toLowerCase();String fullEncodedImage = "data:image/" + format + ";base64," + Base64.getEncoder().encodeToString(bytes);return fullEncodedImage;}} else {String format = getFileExtension(file.getName()).toLowerCase();String fullEncodedImage = "data:image/" + format + ";base64," + Base64.getEncoder().encodeToString(originalInputStream.readAllBytes());return fullEncodedImage;}} catch (Exception e) {logger.error("转换图像文件为Base64时出错: " + imagePath, e);return null;}}/*** 获取文件扩展名** @param fileName* @return*/private static String getFileExtension(String fileName) {int lastIndexOfDot = fileName.lastIndexOf('.');if (lastIndexOfDot == - 1) {// 没有找到扩展名的情况return "";}return fileName.substring(lastIndexOfDot + 1);}/*** 判断word是doc还是docx** @param file* @return*/public String getFileType(File file) {String fileName = file.getName();int dotIndex = fileName.lastIndexOf('.');if (dotIndex > 0 && dotIndex < fileName.length() - 1) {String extension = fileName.substring(dotIndex + 1).toLowerCase();if ("docx".equals(extension)) {return "docx";} else if ("doc".equals(extension)) {return "doc";}}return null;}/*** 给照片添加水印** @param inputStream* @param waterMarkText* @return*/public InputStream addImageWaterMark(InputStream inputStream, String waterMarkText) throws IOException {if (waterMarkText == null || waterMarkText == "") {return inputStream;}BufferedImage image;try {image = ImageIO.read(inputStream);} catch (IOException e) {throw e;}int width = image.getWidth();int height = image.getHeight();BufferedImage watermarkedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);Graphics2D g2d = watermarkedImage.createGraphics();// 绘制原始图像到新图像g2d.drawImage(image, 0, 0, width, height, null);// 设置抗锯齿g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);g2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);// 设置水印的字体和颜色（包括透明度）Font font = new Font("STSong-Light", Font.BOLD, 30); // 可以调整字体大小g2d.setFont(font);g2d.setColor(new Color(0, 0, 0, 255)); // 红色，透明度为 25%g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, 0.2f));// 创建旋转变换AffineTransform originalTransform = g2d.getTransform();AffineTransform rotateTransform = new AffineTransform();rotateTransform.rotate(Math.toRadians(- 30), 0, 0);g2d.setTransform(rotateTransform);// 获取字体度量信息FontMetrics fontMetrics = g2d.getFontMetrics();int watermarkWidth = fontMetrics.stringWidth(waterMarkText);int watermarkHeight = fontMetrics.getHeight();// 将图像用水印铺满for (int x = - width; x < width * 2; x += watermarkWidth + 100) {for (int y = - height; y < height * 2; y += watermarkHeight + 100) {g2d.drawString(waterMarkText, x, y);}}// 恢复原始变换g2d.setTransform(originalTransform);g2d.dispose();// 将带有水印的图像写入ByteArrayOutputStreamByteArrayOutputStream os = new ByteArrayOutputStream();try (ImageOutputStream ios = ImageIO.createImageOutputStream(os)) {if (! ImageIO.write(watermarkedImage, "jpg", ios)) {throw new IOException("Failed to write watermarked image to output stream");}} catch (IOException e) {throw e;} finally {try {os.close();} catch (IOException e) {throw e;}}// 返回处理后的图像流return new ByteArrayInputStream(os.toByteArray());}/*** 给PDF添加水印** @param inputStream* @param waterMarkText* @return*/public InputStream addPdfWaterMark(InputStream inputStream, String waterMarkText) {if (waterMarkText == null || waterMarkText == "") {return inputStream;}OutputStream outputStream = null;PdfReader pdfReader = null;PdfStamper pdfStamper = null;try {// 水印的高和宽int waterMarkHeight = 30;int watermarkWeight = 60;// 水印间隔距离int waterMarkInterval = 100;outputStream = new ByteArrayOutputStream();// 读取PDF文件流pdfReader = new PdfReader(inputStream);// 创建PDF文件的模板，可以对模板的内容修改，重新生成新PDF文件pdfStamper = new PdfStamper(pdfReader, outputStream);// 设置水印字体BaseFont baseFont = BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.EMBEDDED);// 设置PDF内容的Graphic State 图形状态PdfGState pdfGraPhicState = new PdfGState();// 填充透明度pdfGraPhicState.setFillOpacity(0.2f);// 轮廓不透明度pdfGraPhicState.setStrokeOpacity(0.4f);// PDF页数int pdfPageNum = pdfReader.getNumberOfPages() + 1;// PDF文件内容字节PdfContentByte pdfContent;// PDF页面矩形区域com.itextpdf.text.Rectangle pageRectangle;for (int i = 1; i < pdfPageNum; i++) {// 获取当前页面矩形区域pageRectangle = pdfReader.getPageSizeWithRotation(i);// 获取当前页内容，getOverContent表示之后会在页面内容的上方加水印pdfContent = pdfStamper.getOverContent(i);// 获取当前页内容，getOverContent表示之后会在页面内容的下方加水印// pdfContent = pdfStamper.getUnderContent(i);pdfContent.saveState();// 设置水印透明度pdfContent.setGState(pdfGraPhicState);// 开启写入文本pdfContent.beginText();// 设置字体pdfContent.setFontAndSize(baseFont, 15);// 在高度和宽度维度每隔waterMarkInterval距离添加一个水印for (int height = waterMarkHeight; height < pageRectangle.getHeight(); height = height + waterMarkInterval) {for (int width = watermarkWeight; width < pageRectangle.getWidth() + watermarkWeight;width = width + waterMarkInterval) {// 添加水印文字并旋转30度角pdfContent.showTextAligned(Element.ALIGN_LEFT, waterMarkText, width - watermarkWeight,height - waterMarkHeight, 30);}}// 停止写入文本pdfContent.endText();}pdfStamper.close();pdfReader.close();} catch (Exception e) {e.printStackTrace();} finally {try {if (pdfReader != null) {pdfReader.close();}if (inputStream != null) {inputStream.close();}if (outputStream != null) {outputStream.flush();outputStream.close();}} catch (IOException e) {throw new RuntimeException(e);}}return new ByteArrayInputStream(((ByteArrayOutputStream) outputStream).toByteArray());}/*** 给word添加水印** @param inputStream* @param waterMarkText* @return*/public InputStream addWordWaterMark(InputStream inputStream, String waterMarkText) {if (waterMarkText == null || waterMarkText == "") {return inputStream;}try {XWPFDocument doc = new XWPFDocument(inputStream);WordWaterMarker.makeFullWaterMarkByWordArt(doc, waterMarkText, "#d8d8d8", "0.5pt", "-30");ByteArrayOutputStream os = new ByteArrayOutputStream();doc.write(os);return new ByteArrayInputStream(os.toByteArray());} catch (IOException e) {e.printStackTrace();}return null;}
}

2.5model层代码

DownloadFile.java完整代码如下：

package com.example.testdemo.test.model;import lombok.Data;
import java.util.List;/*** 项目名称: testDemo* 作者: zhaojs* 创建日期: 2024年07月04日* 文件说明: 见类描述*/
@Data
public class DownloadFile {/*** 附件id，多个用','隔开*/private String attachmentIds;/*** 文件压缩包名*/private String fileZipName;/*** 水印文字*/private String watermarkText;
}

Attachment.java完整代码如下：

package com.example.testdemo.test.model;import java.time.LocalDateTime;
import java.util.Date;
import java.io.Serializable;import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;/*** 附件表实体类* @author zhaojs* @date 2024-07-04*/
@Data
@TableName("ATTACHMENT")
public class Attachment implements Serializable {/*** 序列化变量*/private static final long serialVersionUID = 697303854047803428L;/*** 主键id*/@TableIdprivate String attachmentId;/*** 文件id*/private String fileId;/*** 文件名*/private String fileName;/*** 文件类型*/private String fileType;/*** 文件大小*/private Double fileSize;/*** 文件路径*/private String filePath;/*** 创建人id*/private String createUserId;/*** 创建人姓名*/private Integer createUserName;/*** 创建时间*/private LocalDateTime createTime;/*** 更新人id*/private String updateUserId;/*** 更新人姓名*/private String updateUserName;/*** 更新时间*/private LocalDateTime updateTime;/*** 文件过期时间*/private LocalDateTime expireTime;
}

2.6dao层代码

AttachmentDao.java完整代码如下，对应的mapper文件自己映射就好，这里就不给出了：

package com.example.testdemo.test.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.testdemo.test.model.Attachment;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;/*** 附件表Dao接口* @author zhaojs* @date 2024-07-04*/
public interface AttachmentDao extends BaseMapper<Attachment> {
}

2.6说明

（1）代码内的数据库表自己创建，参考Attachment.java即可。

（2）到此，就可以使用了，Linux和Windows都可以，启动项目前记得把libreoffice也启起来，也就是1.3启动libreoffice。

（3）若是转换过程发现报错Cause: java.sql.SQLException: Incorrect string value: ‘?μ?èˉ?..’ for column ‘FILE_NAME’ at row 1
; uncategorized SQLException; SQL state [HY000]; error code [1366]; Incorrect string value: ‘?μ?èˉ?..’ for column ‘FILE_NAME’ at row 1; nested exception is java.sql.SQLException: Incorrect string value: ‘?μ?èˉ?..’ for column ‘FILE_NAME’ at row 1] with root cause
则是字符集编码引起的，执行下面命令修改mysql字符集即可：

ALTER TABLE 表名 CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;ALTER DATABASE 数据库名 CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;