把流轉換成String

private String streamTostring(InputStream stream){
    ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
    int len;
    byte[] bytes = new byte[1024];
    try {
        while ((len = stream.read(bytes))!=-1){
        byteArrayOutputStream.write(bytes,0,len);
            }
    } catch (IOException e) {
        e.printStackTrace();
    }
    return  byteArrayOutputStream.toString();

}