//通过地址获取bitmap
    public Bitmap getBitmap(String path) {
        Bitmap bitmap = null;
        try {
            //封装url
            URL url = new URL(path);
            //获得httpurl连接对象
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            //设置连接超时
            connection.setConnectTimeout(5*1000);
            //设置请求方法
            connection.setRequestMethod("GET");
            //判断请求状态码是否连接成功
            if (connection.getResponseCode() == 200) {
                InputStream is = connection.getInputStream();
                //bitmapfactory可以有多种生存bitmap的方法
                bitmap = BitmapFactory.decodeStream(is);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return bitmap;
    }
    //获得字节数组
    public void getBytesByIs(InputStream is) throws IOException {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        int len ;
        byte[] data = new byte[1024];
        while((len = is.read(data))!=-1){
            bos.write(data, 0, len);
        }
        byte[] bytes = bos.toByteArray();
    }