SpringBoot + LibreOffice + Hutool 实现附件预览简单示例

太过爱你忘了你带给我的痛 2023-10-03 17:41 23阅读 0赞

##### 1. 简介 #####

在日常开发中，经常会遇到需要预览附件的需求，如果附件类型为图片、文本、PDF或者网页文件，则直接可以在浏览器预览；如果附件类型为Word、Excel、PPT等文件，则需要通过工具转换为PDF后在浏览器预览。  
本博客使用LibreOffice和Hutool实现文件预览简单示例。  
LibreOffice官网：[https://zh-cn.libreoffice.org/][https_zh-cn.libreoffice.org]

##### 2. 安装Libreoffice #####

*  Windows安装
    
     *  下载介质：[https://zh-cn.libreoffice.org/download/libreoffice/][https_zh-cn.libreoffice.org_download_libreoffice]![41286bcfc8c4e1d24a8df9330dd005c8.png][]![04b330c73ef8ec19f8ec371b597f2115.png][]
     *  安装时依次点击下一步即可(注意记录安装目录，在项目配置文件中需要配置)
 *  Linux安装
    
     *  yum安装
    
        yum -y install libreoffice
        # 安装后的目录为：/usr/lib64/libreoffice
    
     *  乱码问题
    
        # 上传Windows的C:\Windows\Fonts目录中的字体到Linux的/usr/share/fonts/windows目录
        # 执行授权
        chmod 644 /usr/share/fonts/windows/* && fc-cache -fv
 *  官网安装手册[https://zh-cn.libreoffice.org/get-help/install-howto/][https_zh-cn.libreoffice.org_get-help_install-howto]

##### 3. 示例代码 #####

*  创建工程![309967c0f648ad23f2d2e8561efb6532.png][]
 *  修改pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
    	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    	<modelVersion>4.0.0</modelVersion>
    	<groupId>com.c3stones</groupId>
    	<artifactId>spring-boot-libreoffice-demo</artifactId>
    	<version>0.0.1-SNAPSHOT</version>
    	<name>spring-boot-libreoffice-demo</name>
    	<description>Spring Boot Libreoffice Demo</description>
    
    	<parent>
    		<groupId>org.springframework.boot</groupId>
    		<artifactId>spring-boot-starter-parent</artifactId>
    		<version>2.3.4.RELEASE</version>
    		<relativePath />
    	</parent>
    
    	<dependencies>
    		<dependency>
    			<groupId>org.jodconverter</groupId>
    			<artifactId>jodconverter-spring-boot-starter</artifactId>
    			<version>4.4.2</version>
    		</dependency>
    		<dependency>
    			<groupId>org.jodconverter</groupId>
    			<artifactId>jodconverter-local</artifactId>
    			<version>4.4.2</version>
    		</dependency>
    		<dependency>
    			<groupId>org.jodconverter</groupId>
    			<artifactId>jodconverter-core</artifactId>
    			<version>4.4.2</version>
    		</dependency>
    		<dependency>
    			<groupId>org.libreoffice</groupId>
    			<artifactId>ridl</artifactId>
    			<version>7.2.0</version>
    		</dependency>
    		<dependency>
    			<groupId>cn.hutool</groupId>
    			<artifactId>hutool-all</artifactId>
    			<version>5.7.13</version>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-thymeleaf</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-web</artifactId>
    		</dependency>
    	</dependencies>
    
    	<build>
    		<plugins>
    			<plugin>
    				<groupId>org.springframework.boot</groupId>
    				<artifactId>spring-boot-maven-plugin</artifactId>
    			</plugin>
    		</plugins>
    	</build>
    
    </project>

*  创建配置文件application.yml

server:
      port: 8080
    
    spring:
      thymeleaf:
        prefix: classpath:/view/
        suffix: .html
        encoding: UTF-8
        servlet:
          content-type: text/html
        cache: false
      servlet:
        multipart:
          max-file-size: 50MB
          max-request-size: 50MB
    
    # 附件预览
    jodconverter:
      local:
        enabled: true
    #   # 设置LibreOffice目录
        officeHome: D:\LibreOffice
    #   # CentOS 下安装 LibreOffice：
    #   # 1、安装：yum -y install libreoffice
    #   # 2、配置：officeHome: /usr/lib64/libreoffice
    #   # Linux 中文字体乱码解决：
    #   # 1、上传 C:\Windows\Fonts 下的字体到 /usr/share/fonts/windows 目录
    #   # 2、执行命令： chmod 644 /usr/share/fonts/windows/* && fc-cache -fv
    #   # 监听端口,开启多个LibreOffice进程，每个端口对应一个进程
    #   portNumbers: 8100,8101,8102
        portNumbers: 2002
    #   # LibreOffice进程重启前的最大进程数
        maxTasksPerProcess: 10
    #   # 任务在转换队列中的最大生存时间，默认30s
        taskQueueTimeout: 30

*  创建Controller

import java.io.IOException;
    import java.io.InputStream;
    import java.io.OutputStream;
    
    import javax.servlet.http.HttpServletResponse;
    
    import org.apache.tomcat.util.http.fileupload.IOUtils;
    import org.jodconverter.core.DocumentConverter;
    import org.jodconverter.core.office.OfficeException;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.multipart.MultipartFile;
    
    import cn.hutool.core.io.IORuntimeException;
    import cn.hutool.core.io.IoUtil;
    import cn.hutool.core.util.StrUtil;
    
    /**
     * 附件预览Controller
     * 
     * @author CL
     *
     */
    @Controller
    @RequestMapping(value = "/file")
    public class FilePreviewController {
    
    	private static final Logger log = LoggerFactory.getLogger(FilePreviewController.class);
    
    	@Autowired
    	private DocumentConverter documentConverter;
    
    	/**
    	 * 跳转到附件预览和下载页面
    	 * 
    	 * @return
    	 */
    	@RequestMapping(value = "")
    	public String index() {
    		return "fileIndex";
    	}
    
    	/**
    	 * 附件预览
    	 * 
    	 * @param file     附件
    	 * @param response
    	 */
    	@RequestMapping(value = "/preview")
    	@ResponseBody
    	public void preview(MultipartFile file, HttpServletResponse response) {
    		if (file == null) {
    			return;
    		}
    		InputStream inputStream = null;
    		OutputStream outputStream = null;
    		try {
    			inputStream = file.getInputStream();
    			outputStream = response.getOutputStream();
    			String fileName = file.getOriginalFilename();
    			if (StrUtil.endWithAnyIgnoreCase(fileName, ".doc", ".docx", ".xls", ".xlsx", ".csv", ".ppt", ".pptx")) {
    				// 转为PDF
    				documentConverter.convert(inputStream).to(outputStream)
    						.as(documentConverter.getFormatRegistry().getFormatByExtension("pdf")).execute();
    			} else if (StrUtil.endWithAnyIgnoreCase(fileName, ".pdf", ".txt", ".xml", ".md", ".json", ".html", ".htm",
    					".gif", ".jpg", ".jpeg", ".png", ".ico", ".bmp")) {
    				IoUtil.copy(inputStream, outputStream);
    			} else {
    				outputStream.write("暂不支持预览此类型附件".getBytes());
    			}
    		} catch (IORuntimeException e) {
    			log.error("附件预览IO运行异常：{}", e.getMessage());
    		} catch (IOException e) {
    			log.error("附件预览IO异常：{}", e.getMessage());
    		} catch (OfficeException e) {
    			log.error("附件预览Office异常：{}", e.getMessage());
    		} finally {
    			IOUtils.closeQuietly(inputStream);
    		}
    		IoUtil.writeUtf8(outputStream, true);
    	}
    
    }

*  创建附件预览示例页面  
    在resources下新建目录view，在view目录下新建页面：`fileIndex.html`。

<html>
    <head>
    	<title>附件预览和下载</title>
    </head>
    <body>
    	<h5>支持附件类型为：.doc, .docx, .xls, .xlsx, .csv, .ppt, .pptx, .pdf, .txt, .xml, .md, .json, .gif, .jpg, .jpeg, .png, .ico, .bmp</h5>
    	<form id="fileForm" action="" method="post" enctype="multipart/form-data">
    		<i style="color: red">*</i> 上传附件：<input id="file" name="file" type="file" /><br/>
    	</form>
    	<button onclick="preview()">预览</button>
    </body>
    </html>
    <script>
    // 预览方法
    function preview() {
    	// 检查是否为空和大小限制
    	var file = document.getElementById('file').files[0];
    	if (!file) {
    		alert("附件不能为空");
    		return;
    	}
    	var fileSize = file.size;
    	if (fileSize > 50 * 1024 * 1024) {
    		alert("最大支持附件大小为 50MB");
    		return;
    	}
    	
    	// 提交表单
    	var fileForm = document.getElementById('fileForm');
    	fileForm.action = "[[@{/}]]file/preview";  
    	fileForm.submit();
    }
    </script>

*  创建启动类

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    /**
     * 启动类
     * 
     * @author CL
     *
     */
    @SpringBootApplication
    public class Application {
    
    	public static void main(String[] args) {
    		SpringApplication.run(Application.class, args);
    	}
    
    }

##### 4. 测试 #####

*  启动项目
 *  浏览器访问：[http://127.0.0.1:8080/file][http_127.0.0.1_8080_file]![10c6fea70efe3a5b93a0dce1b1485a9d.png][]
 *  测试预览图片![30f31458d05d73abeb90b7a4b3daa098.png][]
 *  测试预览文本![2586e6a2862ec88dc94e9c59eb49a45b.png][]
 *  测试预览Word文件![84cf7ff21c690462c9b4869c115f72ff.png][]
 *  测试预览PPT文件![a952fe1aac12a026af14f315f32b90bd.png][]
 *  测试预览PDF![d5e0b4a74163adb2a7a7f8c0be7fc3d4.png][]

##### 5. 项目地址 #####

[spring-boot-libreoffice-demo][]

[https_zh-cn.libreoffice.org]: https://zh-cn.libreoffice.org/
[https_zh-cn.libreoffice.org_download_libreoffice]: https://zh-cn.libreoffice.org/download/libreoffice/
[41286bcfc8c4e1d24a8df9330dd005c8.png]: https://img-blog.csdnimg.cn/img_convert/41286bcfc8c4e1d24a8df9330dd005c8.png
[04b330c73ef8ec19f8ec371b597f2115.png]: https://img-blog.csdnimg.cn/img_convert/04b330c73ef8ec19f8ec371b597f2115.png
[https_zh-cn.libreoffice.org_get-help_install-howto]: https://zh-cn.libreoffice.org/get-help/install-howto/
[309967c0f648ad23f2d2e8561efb6532.png]: https://img-blog.csdnimg.cn/img_convert/309967c0f648ad23f2d2e8561efb6532.png
[http_127.0.0.1_8080_file]: http://127.0.0.1:8080/file
[10c6fea70efe3a5b93a0dce1b1485a9d.png]: https://img-blog.csdnimg.cn/img_convert/10c6fea70efe3a5b93a0dce1b1485a9d.png
[30f31458d05d73abeb90b7a4b3daa098.png]: https://img-blog.csdnimg.cn/img_convert/30f31458d05d73abeb90b7a4b3daa098.png
[2586e6a2862ec88dc94e9c59eb49a45b.png]: https://img-blog.csdnimg.cn/img_convert/2586e6a2862ec88dc94e9c59eb49a45b.png
[84cf7ff21c690462c9b4869c115f72ff.png]: https://img-blog.csdnimg.cn/img_convert/84cf7ff21c690462c9b4869c115f72ff.png
[a952fe1aac12a026af14f315f32b90bd.png]: https://img-blog.csdnimg.cn/img_convert/a952fe1aac12a026af14f315f32b90bd.png
[d5e0b4a74163adb2a7a7f8c0be7fc3d4.png]: https://img-blog.csdnimg.cn/img_convert/d5e0b4a74163adb2a7a7f8c0be7fc3d4.png
[spring-boot-libreoffice-demo]: https://github.com/C3Stones/blog