android php获取sql row id问题

I am trying to insert empty row in table then get its ID. It is working but it is giving me extra empty lines in output, any idea why? code below:

php:

$query = "INSERT INTO player () VALUES ()";
$mysqli->query($query);

echo  $mysqli->insert_id;

android:

HttpGet getRequest = new HttpGet(url);
HttpResponse response = httpclient.execute(getRequest);
String str = EntityUtils.toString(response.getEntity());
System.out.println("row id: " + str + "end");

result in logs:

05-02 00:24:29.163: I/System.out(28787): row id:  14 

05-02 00:24:29.163: I/System.out(28787): 

05-02 00:24:29.163: I/System.out(28787): 

05-02 00:24:29.163: I/System.out(28787): 

05-02 00:24:29.163: I/System.out(28787): 

05-02 00:24:29.163: I/System.out(28787): end