其实很简单

1.首先引进pom

<dependency>
    <groupId>net.coobird</groupId>
    <artifactId>thumbnailator</artifactId>
    <version>0.4.7</version>            
 </dependency>

2.接下来就是压缩并上传图片的代码了

public String upload(MultipartFile file,HttpServletRequest request) {
        String filename = file.getOriginalFilename();
        String checkImg = ImageUtil.checkImg(filename);
        if (StringUtil.isEmpty(checkImg)){
            throw  new ServiceException(ReturnCode.FILE_INVALID_TYPE);
        }
        File f = new File(uploadPath);
        if (!f.exists()){
            f.mkdir();
        }
        String random = UUID.randomUUID().toString()
        try {
            Thumbnails.of(file.getInputStream()).scale(0.8f).outputFormat("jpg").outputQuality(0.5).toFile(uploadPath + random);
            log.info("上传图片成功,图片路径==>{}",uploadPath);
        } catch (IOException e) {
            log.info("上传图片失败!");
            e.printStackTrace();
        }
        return "/upload/"+random+".jpg";
    }

uploadPath我是配置在.yml文件中的(自己配置图片上传的目标文件夹)

upload:
  path: /data/java/upload/

获取配置的图片上传路径

 @Value("${upload.path}")
  private String uploadPath;

scale 这个参数是图片的缩放比例(根据自己的要求进行设置)

outputFormat 这个参数是吧上传的图片转换为jpg格式(我是这样图片所占
的内存就会小一些,根据自己的需求进行设置)

outputQuality 这个参数是图片的质量大小进行压缩

代码里的 ImageUtil工具类的代码如下(对上传的文件的类型进行限制,自己可以扩展)

public class ImageUtil {
    public static String  checkImg(String uploadContentType){
        String expandedName = "";
        if (uploadContentType.endsWith(".jpg") || uploadContentType.endsWith(".JPG")) {
            // IE6上传jpg图片的headimageContentType是image/pjpeg，而IE9以及火狐上传的jpg图片是image/jpeg
            expandedName = "jpg";
        } else if (uploadContentType.endsWith(".png") || uploadContentType.endsWith(".PNG")) {
            // IE6上传的png图片的headimageContentType是"image/x-png"
            expandedName = "png";
        }
        return expandedName;
    }
}