思路:base64 -> multipartFile – > pdf
base64 -> multipartFile
/ * 将 图片base64 - > MultipartFile * @param base64 * @return */ public static MultipartFile base64MultipartFile(String base64) {
try {
String[] baseStr = base64.split(","); BASE64Decoder base64Decoder = new BASE64Decoder(); byte[] b; b = base64Decoder.decodeBuffer(baseStr[1]); for (int i = 0; i < b.length; ++i) {
if (b[i] < 0) {
b[i] += 256; } } return new BASE64DecodedMultipartFile(b, baseStr[0]); } catch (Exception e) {
e.printStackTrace(); return null; } } multipartFile – > pdf
/ * 将图片转换为PDF文件 * * @param file SpringMVC获取的图片文件 * @return PDF文件 * @throws IOException IO异常 * @throws DocumentException PDF文档异常 */ private static File generatePdfFile(MultipartFile file) throws IOException, DocumentException {
String fileName = file.getOriginalFilename(); String pdfFileName; if (fileName != null) {
pdfFileName = fileName.substring(0, fileName.lastIndexOf(".")) + ".pdf"; } else {
return null; } Document doc = new Document(PageSize.A4, 100, 100, 20, 30); PdfWriter.getInstance(doc, new FileOutputStream(pdfFileName)); doc.open(); doc.newPage(); Image image = Image.getInstance(file.getBytes()); float height = image.getHeight(); float width = image.getWidth(); int percent = getPercent(height, width); image.setAlignment(Image.MIDDLE); image.scalePercent(percent); doc.add(image); doc.close(); return new File(pdfFileName); } / * 等比压缩，获取压缩百分比 * @param height 图片的高度 * @param weight 图片的宽度 * @return 压缩百分比 */ private static int getPercent(float height, float weight) {
float percent; if (height > weight) {
percent = PageSize.A4.getHeight() / height * 100; } else {
percent = PageSize.A4.getWidth() / weight * 100; } // -5 多缩放一点 不影响内容 percent -= 5; return Math.round(percent); } 如果还需要转成multipartFile方便调用api上传的话
pdf file – > multipartFile
FileInputStream input = new FileInputStream(file); MultipartFile multipartFilePDF = new MockMultipartFile("file", file.getName(), "text/plain", IOUtils.toByteArray(input)); pom 依赖 itextpdf
<dependency> <groupId>com.itextpdf</groupId> <artifactId>itextpdf</artifactId> <version>5.5.10</version> </dependency> 版权声明：本文内容由互联网用户自发贡献，该文观点仅代表作者本人。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容， 请联系我们举报，一经查实，本站将立刻删除。
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