base64 转MultipartFile的子类 CommonsMultipartFile

base64 转MultipartFile的子类 CommonsMultipartFile

 /**
     * 获得正确的 图片base64 字符串
     * @param imgStr
     * @return
     */
    public static String getRealImgeStr(String imgStr){
        String[] str = imgStr.split(",");
        return str[1];
    }

    /**
     * base64转File
     * @param base64
     * @return
     */
    public static File base64ToFile(String base64) {
        if(base64==null||"".equals(base64)) {
            return null;
        }
        //getRealImgeStr 方法 截取bese64字符串 逗号后半部分有用的字符串
        byte[] buff= Base64.decode(getRealImgeStr(base64));
        File file=null;
        FileOutputStream fout=null;
        try {
            file = File.createTempFile("tmp", ".jpg");
            fout=new FileOutputStream(file);
            fout.write(buff);
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(fout!=null) {
                try {
                    fout.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return file;
    }

    /**
     * base64转CommonsMultipartFile
     * @param base64filestr
     * @return
     */
    public static CommonsMultipartFile base64toMultipartFile(String base64filestr){

        final File file = CommonUtil.base64ToFile(base64filestr);
        if(file.exists()){
            System.out.print("存在");
            System.out.print("长度"+file.length());
        }
        DiskFileItem item = (DiskFileItem) new DiskFileItemFactory().createItem(file.getName(), "image/jpeg", false, file.getName());
        InputStream input = null;
        try {
            input = new FileInputStream(file);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        OutputStream os = null;
        try {
            os = item.getOutputStream();
            int ret = input.read();
            while ( ret != -1 )
            {
                os.write(ret);
                ret = input.read();
            }
            os.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return new CommonsMultipartFile(item);
    }