java将base64编码字符串还原为字节数组

 /**
     * 图片上传
     * @param imgBase
     * @return
     */
    @PostMapping("/upload")
    public CommonResult upload(String imgBase){
        byte[] b1 = null;
        BASE64Decoder decoder = new BASE64Decoder();
        try{
            if (imgBase.indexOf("data:image/jpeg;base64,") != -1) {
                b1 = decoder.decodeBuffer(imgBase.replaceAll("data:image/jpeg;base64,", ""));
            } else {
                if (imgBase.indexOf("data:image/png;base64,") != -1) {
                    b1 = decoder.decodeBuffer(imgBase.replaceAll("data:image/png;base64,", ""));
                } else {
                    b1 = decoder.decodeBuffer(imgBase.replaceAll("data:image/jpg;base64,", ""));
                }
            }
            for (int i = 0; i < b1.length; ++i) {
                if (b1[i] < 0) {// 调整异常数据
                    b1[i] += 256;
                }
            }
        }catch(Exception e){
            e.printStackTrace();
        }
        //添加图片url；
        String name = UUID.randomUUID().toString().replace("_", "");
        try {
            String upload = new QiniuUploadUtil().upload(name, b1);
            System.out.println("uploaduploadupload"+upload);
            if(imgUrl==null){
                imgUrl=new ArrayList<>();
            }
            imgUrl.add(upload);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return CommonResult.success("1");
    }
}