/**
     *将输入流转化成字符串
     * inputStream 指定的输入流
     */
    public static String getStringFromInputStream(InputStream inputStream) {
        String resultData = null;      //需要返回的结果
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        byte[] data = new byte[1024];
        int len = 0;
        try {
            while((len = inputStream.read(data)) != -1) {
                byteArrayOutputStream.write(data, 0, len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        resultData = new String(byteArrayOutputStream.toByteArray());    
        return resultData;
    }