List<SigninImg> signinImgList=new ArrayList<>();
        for (int i=0;i<10;i++){
            SigninImg img=new SigninImg();
            img.setId((long)i);
            img.setShowOrder(i);
            signinImgList.add(img);
        }
        signinImgList.forEach(action->{System.out.println(JSON.toJSONString(action));});
        //方法一:重写compare方法
        Collections.sort(signinImgList, new Comparator<SigninImg>() {
            @Override
            public int compare(SigninImg o1, SigninImg o2) {
                if(o1.getShowOrder() >o2.getShowOrder()){
                    return -1;
                }
                return 1;
            }
        });
        System.out.println("*****************");
        //方法二:使用stream sorted方法    
        signinImgList=signinImgList.stream().sorted((s2,s1 )->s1.getShowOrder().compareTo(s2.getShowOrder())).collect(Collectors.toList());
        //方法三:使用jdk8的sort方法
        signinImgList.sort((s2,s1)->s1.getShowOrder().compareTo(s2.getShowOrder()));
        signinImgList.forEach(action->{System.out.println(JSON.toJSONString(action));});