How to parse json from a url
<p>I have a url contain all the json format.</p>

<p><a href="http://api.musixmatch.com/ws/1.1/track.lyrics.get?apikey=d34fb59a16877bd1c540aa472491825b&amp;track_id=12414632" rel="nofollow">http://api.musixmatch.com/ws/1.1/track.lyrics.get?apikey=d34fb59a16877bd1c540aa472491825b&amp;track_id=12414632</a></p>

<pre><code>function load() { 
    dashcode.setupParts(); 
    var link = 'http://api.musixmatch.com/ws/1.1/track.search?apikey=d34fb59a16877bd1c540aa472491825b&amp;q_track=back%20to%20december&amp;page_size=10'; 
   req.open = ("GET", link, false); 
   req.onreadystatechange = readXML(); 
   req.send(null); 
}

function readXML(){ 
    alert(req.responseText); 
}
</code></pre>

<p>this code keep saying null all the time.
Are there any way that i can retrieved those json text </p>
