How to use XMLDecoder in JAVA to deserialize an XML

I am trying to use XMLDecoder to deserialize an XML string but it is throwing a java.lang.ArrayIndexOutOfBoundsException.

It seems that the decoder is throwing the exception because if the stream contains no objects (or no more objects) it throws the ArrayIndexOutOfBoundsException but when I print the string it has the correct XML.

The response that it is trying to deserialize is :

<response>
 <isMaster>true</isMaster>
 <success>true</success>
 <sessionsinfo>
 <sessioninfo>
 <sessionID>2018101517193766902543106540502401</sessionID>
 <contactID>9134049637760000241</contactID>
<startTime>2018-10-15T17:19:37.662-05:00</startTime>
 <stopTime>2018-10-15T17:20:32.011-05:00</stopTime>
 <primaryinum>405001000000207</primaryinum>
 <contenttypeofprimaryinum>Audio</contenttypeofprimaryinum>
 <recordedmedia>
<Audio/>
</recordedmedia>
</sessioninfo>
</sessionsinfo>
</response>




public static SessionInfoDevice GetQuerySessionByDevice(String ip, String extension)
    {
        String surl = ip + "/servlet/eQC6?&responseType=XML&interface=ISessionManagement&method=querysessioninfobydevice&device.device=" + extension;
        URL url;
        try {
            url = new URL(surl);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");


conn.setRequestProperty("Accept", "application/json");

    if(conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
        //XMLDecoder dec = new XMLDecoder(conn.getInputStream());
        //Object ob = dec.readObject();
        BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
        StringBuilder sb = new StringBuilder();  
        String line=null;
        int i=0;
        while((line = br.readLine()) != null) {
            if (i == 0 || i==6 || i==7) {
            }else {
                System.out.println(i);
                sb.append(line + '\n'); 
            }
            i++;

        }
        br.close();
        System.out.println("" + sb.toString());
        //XMLDecoder decoder = new XMLDecoder(org.apache.commons.io.IOUtils.toInputStream(sb.toString()));
        XMLDecoder decoder = new XMLDecoder(new BufferedInputStream(new ByteArrayInputStream (sb.toString().getBytes())));
        //SessionInfoDevice sid = (SessionInfoDevice) decoder.readObject();
        Object o = decoder.readObject();
        decoder.close();
        return null;
    }else {
        System.out.println(conn.getResponseCode());
    }
} catch (MalformedURLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();

} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} catch (Exception e) {
    e.printStackTrace();
}

return null;
//return null;

}