java图片上传

1、java将图片转成base64返回前端,前端解析展示

/***
     * 上传证明材料
     * @param files
     * @param request
     * @return
     */
    @RequestMapping(value = "/bitchUploadFile", method = {RequestMethod.POST, RequestMethod.GET})
    @ResponseBody
    public ResponseResult bitchUploadFile(@RequestParam(value = "files", required = false) MultipartFile[] files, HttpServletRequest request) {
        log.info("进入上传证件方法。。。");
        ResponseResult res = new ResponseResult();
        byte[] data = null;
        List<String> urls = new ArrayList<>();
        if (null != files && files.length > 0) {
            for (MultipartFile file : files) {
                try {
                    // 判断图片大小是否大于1M
                    if (file == null || file.isEmpty() || file.getSize() > UPLOAD_FILE_SIZE) {
                        return ResponseResult.FAIL("上传文件为空或者超过规定的大小");
                    }
                    String[] suffixNamesNotDel = {"jpg", "jpeg", "png", "JPG", "JPEG", "PNG"};
                    String[] suffixNames = {".jpg", ".jpeg", ".png", ".JPG", ".JPEG", ".PNG"};
                    List<String> suffixNamesNotDelList = Arrays.asList(suffixNamesNotDel);
                    List<String> suffixNamesList = Arrays.asList(suffixNames);
                    // 获取图片的文件名
                    String fileName = file.getOriginalFilename();
                    int dotIndex = fileName.lastIndexOf(".");
                    if (dotIndex < 0) {
                        dotIndex = fileName.length();
                    }
                    //通过判断后缀判断
                    String suffixName = fileName.substring(dotIndex);
                    //根据文件头名判断文件实际类型
                    boolean su = suffixNamesList.contains(suffixName);
                    // 获取图片的扩展名
                    String extensionName = fileName.substring(fileName.lastIndexOf(".") + 1);
                    if (su) {
                        String uploadUrl = "";
                        //上传文件返回服务器存储路径（公用方法）
                        String db = "demo";
                        uploadUrl = saveFile(extensionName, db, file);
                        //使用base64编码返回前端
                        InputStream in = new FileInputStream(uploadUrl);
                        data = new byte[in.available()];
                        in.read(data);
                        in.close();
                        //对字节数组进行base64编码
                        BASE64Encoder encoder = new BASE64Encoder();
                        String strBase64 ="data:image/jpeg;base64,"+ encoder.encode(data);
                        urls.add(strBase64);
                        res = ResponseResult.SUCCESS(urls);
                    } else {
                        return ResponseResult.FAIL("请上传格式为jpg和png的图片文件");
                    }
                } catch (Exception e) {
                    log.error("上传图片失败" + e);
                    return ResponseResult.FAIL("上传图片失败");
                }
            }
        }
        return res;
    }


    /**
     * @param extensionName 原文件扩展名
     * @param db            Business differentiation区分不同业务，避免上传文件名相同
     * @param filedata      上传的文件数据
     * @Description 文件上传到配置文件 common.properties中的image.storage.root.path路径上
     */
    public String saveFile(String extensionName, String db, MultipartFile filedata) {
        // 新的图片文件名 = 获取时间戳+"."图片扩展名
        String newFileName = db + String.valueOf(System.currentTimeMillis()) + "." + extensionName;
        String saveFilePath = "";
        String preImgUrl = "";
        FileOutputStream out = null;
        try {
            // 根据配置文件获取服务器图片存放路径
            //这里封装了读取配置文件的方法 配置文件中有图片的存放地址和获取地址
            // 根据配置文件获取图片上传路径
            saveFilePath = "D:/aWangzhaung/tools";
            preImgUrl = "D:/aWangzhaung/tools";
            /* 构建文件目录 */
            File fileDir = new File(saveFilePath);
            if (!fileDir.exists()) {
                fileDir.mkdirs();
            }
            out = new FileOutputStream(saveFilePath + File.separator
                    + newFileName);
            // 写入文件
            out.write(filedata.getBytes());
            out.flush();
        } catch (Exception e) {
            log.error("上传图片失败" + e);
            return "";
        } finally {
            if (out != null) {
                try {
                    out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return preImgUrl + "/" + newFileName;
}

2、Java 前端将图片转成base64上传

     /***
     * 上传证明材料
     * @param tempMap
     * @return
     */
    @RequestMapping(value = "/bitchUploadFile", method = RequestMethod.POST)
    @ResponseBody
    public ResponseResult bitchUploadFile(@RequestBody Map<String, Object> tempMap, HttpServletRequest request) {
        ResponseResult res = new ResponseResult();
        try {
            String imageUrl = "";
            String preImgUrl = "";
            String file = (String) tempMap.get("file");
            log.info("file===========" + file);
            try {
                if (StringUtils.isEmpty(file)) {
                    return ResponseResult.FAIL("参数异常");
                }
                String[] jsonParames = file.split(":");
                String consultId = getRandomFileName();22                 if (jsonParames[1] != null && !"".equals(jsonParames[1])) {
                    String savePath = basePath(consultId);
                    String imageBase = jsonParames[1];
                    try {
                        // 文件名称
                        String baseFileName = UUID.randomUUID().toString().replace("-", "").toUpperCase() + ".png";
                        imageBase = imageBase.split(";base64,")[1];
                        FileOutputStream out;

                        out = new FileOutputStream(savePath + baseFileName);
                        BASE64Decoder decoder = new BASE64Decoder();
                        byte[] imageByte = decoder.decodeBuffer(imageBase);
                        // 调整异常数据
                        for (int i = 0; i < imageByte.length; ++i) {
                            if (imageByte[i] < 0) {
                                imageByte[i] += 256;
                            }
                        }
                        out.write(imageByte);
                        out.close();
                        //图片存储路径
                        preImgUrl = "/static/images/image";
                        imageUrl = preImgUrl + "/" + consultId + "/" + baseFileName;
                        //返回图片存储url给前端
                        res = ResponseResult.SUCCESS(imageUrl);
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                } else {
                    res = ResponseResult.FAIL("图片格式异常");
                }
            } catch (Exception e) {
                e.printStackTrace();
                res = ResponseResult.FAIL("接口调用异常");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

        return res;
    }
    
    private String basePath(String consultId) {
        // 图片存放路径
        String saveFilePath = "/nfs/static/images/image";
        String savePath = saveFilePath + "/" + consultId + "/";
        File basePath = new File(savePath);
        // 目录不存在就创建目录
        if (!basePath.exists()) {
            basePath.mkdirs();
        }
        return savePath;
    }

    /**
     * 获取随机数 19位 包含当前时间
     *
     * @return
     */
    public String getRandomFileName() {

        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyyMMddHHmmss");
        Date date = new Date();
        String str = simpleDateFormat.format(date);
        Random random = new Random();
        // 获取5位随机数
        int ranNum = (int) (random.nextDouble() * (99999 - 10000 + 1)) + 10000;

        return str + ranNum;
    }