java實現后台上傳壓縮圖片

控制器的方法
public ResultMap fileUpload(@RequestParam("file") MultipartFile file) {
 String pictureName = DateUtil.getAllTime();
 //獲取壓縮后的圖片名稱，隨機生成
 String smallerPictureName = UUID.randomUUID().toString();
 try {
 //未壓縮前的上傳路徑
 String fileSavePath = getFileUploadPath() + "/image/" + pictureName + ".jpg";
 File tempFile = new File(fileSavePath);
 file.transferTo(tempFile);
 //壓縮后的路徑
 String smallFileSavePath = getFileUploadPath()+"/image/"+smallerPictureName+".jpg";
 //獲取文件大小 KB
 long size = file.getSize()/1024;
 //判斷文件大小對圖片質量進行壓縮,尺寸不變，范圍0.01~1.0,值越低壓縮效率越高。圖片低於600K不進行壓縮
 if(size>=7380){
 Thumbnails.of(fileSavePath).scale(1f).outputQuality(0.01f).toFile(smallFileSavePath);
 tempFile.delete();
 return getResultMap(SUCCESS_CODE,smallerPictureName);
 }else if(size>=4096&&size<7380){
 Thumbnails.of(fileSavePath).scale(1f).outputQuality(0.2f).toFile(smallFileSavePath);
 tempFile.delete();
 return getResultMap(SUCCESS_CODE,smallerPictureName);
 }else if(size>=1024&&size<4096){
 Thumbnails.of(fileSavePath).scale(1f).outputQuality(0.3f).toFile(smallFileSavePath);
 tempFile.delete();
 return getResultMap(SUCCESS_CODE,smallerPictureName);
 }else if(size>=600&&size<1024){
 Thumbnails.of(fileSavePath).scale(1f).outputQuality(1f).toFile(smallFileSavePath);
 tempFile.delete();
 return getResultMap(SUCCESS_CODE,smallerPictureName);
 }else{
 return getResultMap(SUCCESS_CODE,pictureName);
 }
 } catch (Exception e) {
 return getResultMap(ERROR_CODE,"圖片上傳失敗，請稍后重試，或聯系管理員");
 }
}

HTML頁面

layui.use(['form','layer','upload'], function(){
 var $ = layui.$, form = layui.form, upload = layui.upload, layer = layui.layer;

 // 上傳縮略圖
 upload.render({
 elem: '.thumbBox',
 data: {typePicture: $('#typePicture').val(), sortPicture: $('#sortPicture').val()},
 url: '/kaptcha/fileUpload',

 before: function(obj){
 //預讀本地文件，如果是多文件，則會遍歷。(不支持ie8/9)
 layer.load();
 obj.preview(function(index, file, result){
 $('.thumbImg').attr('src', result);
 });
 },
 done: function(res){
 // alert("圖片上傳成功嗎，保存后生效");
 layer.closeAll('loading');
 $("#pictureId").val(res.data);
 $('.thumbBox').css("background","#fff");
 if(res.code != 0){
 alert(res.data);
 }
 }
 });



HTML頁面是我目前所用的，可能會有許多不足，多多見諒！
我只是一個小白