JAVA 使用Thumbnails压缩MultipartFile，并转换为Base64

public String fileTobase64(MultipartFile file) throws Exception {
		String return_base64="";
		File tmpFile = new File("/" + UUID.randomUUID()+ file.getOriginalFilename().substring(file.getOriginalFilename().lastIndexOf(".")));
		file.transferTo(tmpFile);
		if (!file.isEmpty()) {
			if (file.getSize() > 51200) {
			  //大于50K进行压缩
				Thumbnails.of(tmpFile).scale(0.1f).toFile(tmpFile);
			}
			byte[] data = new byte[1024];
			FileInputStream fis = new FileInputStream(tmpFile);
			ByteArrayOutputStream bos = new ByteArrayOutputStream(1024);
			int n;
			while ((n = fis.read(data)) != -1) {
				bos.write(data, 0, n);
			}
			fis.close();
			data = bos.toByteArray();
			bos.close();
			tmpFile.delete();
			return_base64="data:" + file.getContentType() + ";base64," + base64.getEncoder().encodeToString(data);
		}
		return return_base64;
	}

Thumbnails.jar-下载地址：https://repo1.maven.org/maven2/net/coobird/thumbnailator/