Android 图片转二进制流及二进制转字符串

public static byte[] readStream(String imagepath) throws Exception {
    FileInputStream fs = new FileInputStream(imagepath);
    ByteArrayOutputStream outStream = new ByteArrayOutputStream();
    byte[] buffer = new byte[1024];
    int len = 0;
    while (-1 != (len = fs.read(buffer))) {
        outStream.write(buffer, 0, len);
    }
    outStream.close();
    fs.close();
    return outStream.toByteArray();
}

// 二进制转字符串
public static String byte2hex(byte[] b)
{
    StringBuffer sb = new StringBuffer();
    String tmp = "";
    for (int i = 0; i < b.length; i++) {
        tmp = Integer.toHexString(b[i] & 0XFF);
        if (tmp.length() == 1){
            sb.append("0" + tmp);
        }else{
            sb.append(tmp);
        }

    }
    return sb.toString();
}