Getting Product information like name, price etc using barcode number

I am developing an app which uses barcode to get the product information of items after scanning the barcode.

I don't want the user to install ZXing barcode app separately so I embedded the ZXing code into my project. So I was able to obtain the barcode ID number.

I want to get the product information like name, manufacturer, price etc using the bar code number using google search api for shopping.

Here is the code I have used

public class JSONExampleActivity extends Activity {

    TextView httpStuff; 
    DefaultHttpClient client; 
    JSONObject json;  

    final static String URL = "https://www.googleapis.com/shopping/search"; 
    String upc = "/v1/public/products?country=US&q=691464717759&restrictBy=gtin=691464717759";

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);          

        httpStuff = (TextView) findViewById(R.id.tvHttp); 
        client = new DefaultHttpClient(); 
        new Read().execute("items");                
    }

    public JSONObject products(String upc)  throws ClientProtocolException, IOException, JSONException {     
        StringBuilder url = new StringBuilder(URL); 
        url.append(upc);
        HttpGet get = new HttpGet(url.toString());     
        HttpResponse r = client.execute(get);   
        int status = r.getStatusLine().getStatusCode(); 

        if (status == 200) {
            HttpEntity e = r.getEntity();         
            String data = EntityUtils.toString(e);         
            JSONObject timeline = new JSONObject(data); 

            return timeline;    
        } 
        else {         
            Toast.makeText(JSONExampleActivity.this, "error", Toast.LENGTH_SHORT);