java 使用OpenOffice文件实现预览

1.安装OpenOffice软件

安装教程：https://jingyan.baidu.com/article/c275f6ba12c07ce33d756732.html

2.安装完成后，创建项目，pom重要的jar包

 <!-- https://mvnrepository.com/artifact/org.jodconverter/jodconverter-core -->
 <dependency>
     <groupId>org.jodconverter</groupId>
     <artifactId>jodconverter-core</artifactId>
     <version>4.0.0-RELEASE</version>
 </dependency>

3.核心代码

项目启动：

 package com.example.demo;

 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;

 @SpringBootApplication
 public class DemoApplication {

     public static void main(String[] args) {
         SpringApplication.run(DemoApplication.class, args);
     }
 }

控制层代码：

 package com.example.demo;

 import com.example.util.FileUtil;
 import com.example.util.Office2PDF;

 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestMapping;

 import javax.servlet.http.HttpServletResponse;
 import java.io.FileInputStream;
 import java.io.InputStream;
 import java.io.OutputStream;

 @ComponentScan
 @Controller
 @RequestMapping("/test")
 public class ReadAndDownLoad {
     //base路径
     @Value("${BASE_PATH}")
     private  String BASE_PATH ;

     /**
      *
      * @return choose页面
      */
     @RequestMapping("/choose")
     public String chooseFile(){
         return "ShowChoose";
     }

     /**
      *
      * @param res 响应对象
      * @param fileName 请求预览文件名
      * @throws Exception
      */
     @RequestMapping("/read/{fileName}")
     public void readFile(HttpServletResponse res , @PathVariable String fileName) throws Exception{
         InputStream in = null;
         OutputStream out = null;
         String filePath =  fileHandler(fileName);
         //判断是pdf还是word还是excel
         //若是pdf直接读 否则转pdf 再读  //
        try{
            if(filePath != null){
                in = new FileInputStream(filePath);
            }
            res.setContentType("application/pdf");
            out = res.getOutputStream();
            byte[] b = new byte[1024];
            int len = 0;
            while((len = in.read(b)) != -1){
                out.write(b);
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            if(in != null){
                in.close();
            }
            if(out != null){
                out.close();
            }
        }
     }

     /**
      * 文件处理
      * @param fileName
      * @return
      */
     public String fileHandler(String fileName){
         String fileSuffix = FileUtil.getFileSuffix(fileName);
         System.out.println(fileSuffix);
         if("pdf".equals(fileSuffix))
         {
             return BASE_PATH + fileName;
         }
         else
         {
             return Office2PDF.openOfficeToPDF(BASE_PATH + fileName).getAbsolutePath();
         }

     }
 }

文件转换核心代码：

 package com.example.util;
 import org.jodconverter.OfficeDocumentConverter;
 import org.jodconverter.office.DefaultOfficeManagerBuilder;
 import org.jodconverter.office.OfficeException;
 import org.jodconverter.office.OfficeManager;

 import java.io.File;
 import java.util.regex.Pattern;

 public  class Office2PDF {
     //文件转换pdf成功后保存的地址
     private static   String SAVE_PATH = "E:/pdfFile/";
     private Office2PDF(){}

     /**
      * 将office格式的文件转为pdf
      * @param sourceFilePath 源文件路径
      * @return
      */
     public static   File openOfficeToPDF(String sourceFilePath){
         return office2pdf(sourceFilePath);
     }

     /**
      * 将office文档转换为pdf文档
      * @param sourceFilePath 原文件路径
      * @return
      */
     public static   File office2pdf(String sourceFilePath){
         OfficeManager officeManager = null;
         try{
             if(StringUtil.isEmpty(sourceFilePath))
             {
                 //打印日志...
                 return null;
             }
             File sourceFile = new File(sourceFilePath);
             if(!sourceFile.exists())
             {
                 //打印日志...
                 return null;
             }

             String after_convert_file_path = getAfterConverFilePath(sourceFilePath);
             //启动openOffice
             officeManager = getOfficeManager();
             OfficeDocumentConverter converter = new OfficeDocumentConverter(officeManager);
             return convertFile(sourceFile,after_convert_file_path,sourceFilePath,converter);
         }catch (Exception e){
             e.printStackTrace();
             System.out.println("转换异常");
         }finally {
            if(officeManager != null){
                try {
                    officeManager.stop();
                } catch (OfficeException e) {
                    e.printStackTrace();
                }
            }
         }
         return null;
     }

     /**
      * 转换文件
      * @param sourceFile 原文件
      * @param after_convert_file_path 转换后存放位置
      * @param sourceFilePath 原文件路径
      * @param converter 转换器
      * @return
      */
     public static File convertFile(File sourceFile,
                            String after_convert_file_path,String sourceFilePath,OfficeDocumentConverter converter) throws OfficeException {
         File outputFile = new File(after_convert_file_path);
         if(!outputFile.getParentFile().exists()){
             //如果上级目录不存在也就是E:/pdfFile这个文件夹不存在则创建一个
             outputFile.getParentFile().mkdirs();
         }
             converter.convert(sourceFile,outputFile);
         return outputFile;
     }

     public static OfficeManager getOfficeManager(){
         DefaultOfficeManagerBuilder builder = new DefaultOfficeManagerBuilder();
         builder.setOfficeHome(getOfficeHome());
         OfficeManager officeManager = builder.build();
         try {
             officeManager.start();
         } catch (OfficeException e) {
             //打印日志
             System.out.println("start openOffice Fail!");
             e.printStackTrace();
         }
         return officeManager;
     }

     /**
      * 获取转换后文件存放的路径
      * @param sourceFilePath 源文件
      * @return
      */
     public static   String getAfterConverFilePath(String sourceFilePath){
         //截取源文件文件名
         String sourceFileName = sourceFilePath.substring(sourceFilePath.lastIndexOf("/") + 1);
         return SAVE_PATH + sourceFileName.replaceAll("\\."+FileUtil.getFileSuffix(sourceFileName),".pdf");
     }

     /**
      * 获取openOffice的安装目录
      * @return
      */
     public static String getOfficeHome(){
         String osName = System.getProperty("os.name");
         if(Pattern.matches("Windows.*",osName))
         {
             return "C:/Program Files (x86)/OpenOffice 4";
         }
         else if(Pattern.matches("Linux.*",osName))
         {
             return "/usr/temp";
         }
         else if (Pattern.matches("Mac.*",osName))
         {
             return "/Application/openOfficeSoft";
         }
         return null;
     }
 }

工具类：

 package com.example.util;

 public final  class FileUtil {
     private FileUtil(){}

     /**
      * 获取后缀
      * @param fileName 文件名
      * @return 后缀名
      */
     public static String getFileSuffix(String fileName){
         if(StringUtil.isEmpty(fileName) || fileName.lastIndexOf(".")<0 ){
             return "error";
         }
         return fileName.substring(fileName.lastIndexOf(".")+1);
     }
 }

 package com.example.util;

 public final class StringUtil {
     private StringUtil(){}

     public static boolean isEmpty(String target){
         return "".equals(target) || null ==target;
     }
 }

页面代码：

 <!DOCTYPE html>
 <html lang="en">
 <head>
     <meta charset="UTF-8">
     <title>文件预览</title>
 </head>
 <body>
     <p>文件预览：</p><button id="show1">点击预览</button>
     <script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
     <script>
         $("#show1").click(function(){
             window.open("http://localhost:8080/test/read/"+"qqq.ppt");
         });

     </script>
 </body>
 </html>

配置文件：

 #返回的前缀   目录对应src/main/webapp下
 spring.mvc.view.prefix=/
 #返回的后缀
 spring.mvc.view.suffix=.html
 #预览文件的地址
 BASE_PATH=C:/Users/Administrator/Desktop/

pom文件：

 <?xml version="1.0" encoding="UTF-8"?>
 <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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>

     <groupId>com.example</groupId>
     <artifactId>demo</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <packaging>jar</packaging>

     <name>demo</name>
     <description>Demo project for Spring Boot</description>

     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
         <version>2.0.4.RELEASE</version>
         <relativePath/> <!-- lookup parent from repository -->
     </parent>

     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>
     </properties>

     <dependencies>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>

         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>

         <!-- https://mvnrepository.com/artifact/org.jodconverter/jodconverter-core -->
         <dependency>
             <groupId>org.jodconverter</groupId>
             <artifactId>jodconverter-core</artifactId>
             <version>4.0.0-RELEASE</version>
         </dependency>

     </dependencies>

     <build>
         <plugins>
             <plugin>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-maven-plugin</artifactId>
             </plugin>
         </plugins>
     </build>

 </project>

项目结构如下：