springMVC将PDF转换成图片

素颜马尾好姑娘i 2022-03-17 06:26 163阅读 0赞

## springMVC将PDF转换成图片 ##

1.  maven代码

<dependency>
               <groupId>org.apache.pdfbox</groupId>
               <artifactId>pdfbox</artifactId>
               <version>2.0.13</version>
           </dependency>

1.  java代码

@RequestMapping(value = "/file-to-img", method = RequestMethod.GET)
    public ResponseEntity<byte[]> fileToImg(String pdfFile) throws IOException { 
       
       if (StringUtils.isBlank(pdfFile)) { 
       	return new ResponseEntity<>(HttpStatus.NOT_FOUND);
       }
       try (PDDocument pdDocument = PDDocument.load(new File(pdfFile)) { 
       	PDFRenderer pdfRenderer = new PDFRenderer(pdDocument);
       	for (int i = 0; i < pdDocument.getNumberOfPages(); i++) { 
       		BufferedImage image = pdfRenderer.renderImageWithDPI(i, 96f);
       		if (image != null) { 
       			images.add(image);
       		}
       	}
       }
       // 拼接图片
       int width = 0, height = 0;
       for (BufferedImage image : images) { 
       		width = image.getWidth() > width ? image.getWidth() : width;
       		height += image.getHeight();
       }
       BufferedImage pdfImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
       Graphics2D g2d = pdfImage.createGraphics();
       height = 0;
       for (BufferedImage image : images) { 
       		g2d.drawImage(image, (width - image.getWidth()) / 2, height, image.getWidth(), image.getHeight(), null);
       		height += image.getHeight();
       }
       g2d.dispose();
       HttpHeaders headers = new HttpHeaders();
       headers.setContentType(MediaType.IMAGE_JPEG);
       try (ByteArrayOutputStream os = new ByteArrayOutputStream()) { 
       		ImageIO.write(pdfImage, "jpg", os);
       		return new ResponseEntity<>(os.toByteArray(), headers, HttpStatus.OK);
       }
    }