【优化版】Java文件上传数据库(并保存本地)、word转pdf并进行页面预览

迈不过友情╰ 2022-05-10 08:16 206阅读 0赞

上一篇文件上传，是将路径等文件信息存进log\_file临时表，内容二进制存入数据库Test表，这种逻辑是在上传文件到数据库的同时，将word转成pdf，内容以二进制存test表。页面预览调用的是test表的内容。  
上一篇链接：[链接地址。][Link 1]  
下面进一步优化：  
**具体逻辑**：删除原数据表Test，路径等文件信息依旧存log\_file表。文件预览时，判断文件类型，如果为word类型，进行转换pdf展示；反之直接展示文件。  
word类型条件满足后，进一步判断文件是否已经转换过(判断依据是根据路径下文件名查找相同文件名的pdf文件是否存在)，如果同名的pdf文件存在，表示已经转换过，直接展示；如果不存在，word转换pdf，再展示。

代码如下：

public void world(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws IOException {
            List<LogFile> files = terminalServiceImpl.world();
            //用作实例展示，在这取得是数据库第二条信息：以word文件展示。
            String path = files.get(1).getFilePath();
            String filename=files.get(1).getFileName();
    
            //1.根据文件后缀获取文件类型
            File wordName=new File(filename);
            String fileName=wordName.getName();
            String fileTyle=fileName.substring(fileName.lastIndexOf("."),fileName.length());
            logger.info("------文件后缀名------"+fileTyle);
    
            //如果文件类型为word,需要先转换成pdf
            if(fileTyle.equals(".doc")||fileTyle.equals(".docx")){
                    //1.判断文件是否已经转换pdf,文件是否存在：文件前缀+.pdf(word是否已经转换过pdf)，如果存在直接展示pdf
                    File fileOne = new File(path);
                    String caselsh = filename.substring(0,filename.lastIndexOf("."));
                    logger.info("------pdf文件名字------"+caselsh+"pdf.pdf");
    //                File fileIf = new File(fileOne+"\\" + caselsh+".pdf");
                    String filePath=(fileOne+"\\" + caselsh+"pdf.pdf");
                    File fileIf=new File(filePath);
                    if(!fileIf.exists()){
                        String pdfFilePath = OpenOfficeUtil.wordToPDF(path,filename);
                        System.err.println(pdfFilePath);
                        FileInputStream fileInputStream = new FileInputStream(pdfFilePath);
                        byte[] content = new byte[fileInputStream.available()];
                        fileInputStream.read(content);
                        fileInputStream.close();
                        ServletOutputStream servletOutputStream = httpServletResponse.getOutputStream();
                        if (servletOutputStream != null && content != null){
                            httpServletResponse.setContentType("application/pdf");
                            httpServletResponse.setContentLength(content.length);
                            httpServletResponse.setHeader("Expires","0");
                            httpServletResponse.setHeader("Cache-Control","must-revalidate,post-check=0,pre-check=0");
                            httpServletResponse.setHeader("Pragma","public");
                            servletOutputStream.write(content);
                            servletOutputStream.flush();
                            servletOutputStream.close();
                        }
                    }else{
                        File file3 = new File(filePath);
                        //获取pdf文件路径,内容做展示
                        byte[] resultE = new byte[(int) file3.length()];
                        FileInputStream fis = new FileInputStream(file3);
                        fis.read(resultE); //read file into bytes[]
                        fis.close();
                        ServletOutputStream servletOutputStream = httpServletResponse.getOutputStream();
                        if (servletOutputStream != null && resultE != null){
                            httpServletResponse.setContentType("application/pdf");
                            httpServletResponse.setContentLength(resultE.length);
                            httpServletResponse.setHeader("Expires","0");
                            httpServletResponse.setHeader("Cache-Control","must-revalidate,post-check=0,pre-check=0");
                            httpServletResponse.setHeader("Pragma","public");
                            servletOutputStream.write(resultE);
                            servletOutputStream.flush();
                            servletOutputStream.close();
                        }
                }
            }else{
                File file = new File(path);
                File file2 = new File(file+"\\" + filename);
                //获取pdf文件路径,内容做展示
                byte[] result = new byte[(int) file2.length()];
                FileInputStream fis = new FileInputStream(file2);
                fis.read(result); //read file into bytes[]
                fis.close();
                ServletOutputStream servletOutputStream = httpServletResponse.getOutputStream();
                if (servletOutputStream != null && result != null){
                    httpServletResponse.setContentType("application/pdf");
                    httpServletResponse.setContentLength(result.length);
                    httpServletResponse.setHeader("Expires","0");
                    httpServletResponse.setHeader("Cache-Control","must-revalidate,post-check=0,pre-check=0");
                    httpServletResponse.setHeader("Pragma","public");
                    servletOutputStream.write(result);
                    servletOutputStream.flush();
                    servletOutputStream.close();
                }
            }
       }

[Link 1]: https://blog.csdn.net/qq_39629277/article/details/82842835