我刚刚完成了这个工作。这就是我使用 HttpURLConnection 和 AsyncTask 实现它的原因（我只是打电话给 https://www.googleapis.com/books/v1/volumes?q=isbn ：+ yourISBN并解析JSON）：

  //从Barcode Scanner接收到的ISBN。发送到GoogleBooks以获取图书信息。 
 class GoogleApiRequest扩展AsyncTask< String，Object，JSONObject> {

 @Override 
保护无效onPreExecute（）{
 //检查网络连接。 
 if（isNetworkConnected（）== false）{
 //取消请求。 
 Log.i（getClass（）。getName（），未连接到互联网）; 
取消（true）; 
 return; 

 $ b @Override 
 protected JSONObject doInBackground（String ... isbns）{
 // Stop if cancel 
 if（isCancelled（）） {
返回null; 
} 

字符串apiUrlString =https://www.googleapis.com/books/v1/volumes?q=isbn：+ isbns [0]; 
尝试{
 HttpURLConnection连接= null; 
 //建立连接。 
尝试{
 URL url = new URL（apiUrlString）; 
 connection =（HttpURLConnection）url.openConnection（）; 
 connection.setRequestMethod（GET）; 
 connection.setReadTimeout（5000）; // 5秒
 connection.setConnectTimeout（5000）; // 5秒
} catch（MalformedURLException e）{
 //不可能：应用中使用的唯一两个URL取自字符串资源。 
 e.printStackTrace（）; 
} catch（ProtocolException e）{
 //不可能：GET是一个完全有效的请求方法。 
 e.printStackTrace（）; 
} 
 int responseCode = connection.getResponseCode（）; 
 if（responseCode！= 200）{
 Log.w（getClass（）。getName（），GoogleBooksAPI request request failed。Response Code：+ responseCode）; 
 connection.disconnect（）; 
返回null; 
} 

 //从响应中读取数据。 
 StringBuilder builder = new StringBuilder（）; 
 BufferedReader responseReader = new BufferedReader（new InputStreamReader（connection.getInputStream（）））; 
 String line = responseReader.readLine（）; 
 while（line！= null）{
 builder.append（line）; 
 line = responseReader.readLine（）; 
} 
 String responseString = builder.toString（）; 
 Log.d（getClass（）。getName（），Response String：+ responseString）; 
 JSONObject responseJson = new JSONObject（responseString）; 
 //关闭连接并返回响应代码。 
 connection.disconnect（）; 
 return responseJson; 
} catch（SocketTimeoutException e）{
 Log.w（getClass（）。getName（），Connection timed out。Returning null）; 
返回null; 
} catch（IOException e）{
 Log.d（getClass（）。getName（），连接到Google Books API时发生IOException）; 
 e.printStackTrace（）; 
返回null; 
} catch（JSONException e）{
 Log.d（getClass（）。getName（），连接到Google Books API时发生JSONException）; 
 e.printStackTrace（）; 
返回null; 

 $ b @Override 
 protected void onPostExecute（JSONObject responseJson）{
 if（isCancelled（））{
 // Request is cancelled due to无网络连接。 
 showNetworkDialog（）; 
} else if（responseJson == null）{
 showSimpleDialog（getResources（）。getString（R.string.dialog_null_response））; 
} 
其他{
 //一切顺利。用新的JSONObject做些什么。 



 $ b protected boolean isNetworkConnected（）{

 //必要时实例化mConnectivityManager 
 if（mConnectivityManager == null）{
 mConnectivityManager =（ConnectivityManager）getSystemService（Context.CONNECTIVITY_SERVICE）; 
} 
 //设备是否连接到互联网？ 
 NetworkInfo networkInfo = mConnectivityManager.getActiveNetworkInfo（）; 
 if（networkInfo！= null&& amp; networkInfo.isConnected（））{
 return true; 
} else {
 return false; 
} 
} 
 

我将对话方法的代码省略为他们不相关。希望这有助于。

Hi I'm new to Android and using web APIs. I'm currently writing an application that can scan a barcode from a book and then search Google Books for it.

So far I implemented Scandit into my application and I registered and got the API key from Google API console for Books API. From there I do not know how to continue and start coding it. So far from my understanding it requires me make a request data via uri but I'm stuck on how to actually code it. I'm wondering if anyone could point me to the right direction or provide a sample code that shows how to fetch data using URI.

I also downloaded the zipped Book API Jar libraries do I need to make use of this? I ask this because from a question on Google Places API on this website, one of the answer said that all you need is to use Google API as the build target and it doesn't require any Jar files but does this apply to Books API as well?

Also I'm using Eclipse, should I set my build target to be Google APIs 16? I'm guessing this is right since I plan to use Google Maps in future with this app.

Thanks this is first time I asked a question on here.

I just finished doing this myself. This is how I implemented it using an HttpURLConnection and an AsyncTask (I just call "https://www.googleapis.com/books/v1/volumes?q=isbn:"+yourISBN and parse the JSON):

// Received ISBN from Barcode Scanner. Send to GoogleBooks to obtain book information.
class GoogleApiRequest extends AsyncTask<String, Object, JSONObject>{

    @Override
    protected void onPreExecute() {
        // Check network connection.
        if(isNetworkConnected() == false){
            // Cancel request.
            Log.i(getClass().getName(), "Not connected to the internet");
            cancel(true);
            return;
        }
    }
    @Override
    protected JSONObject doInBackground(String... isbns) {
        // Stop if cancelled
        if(isCancelled()){
            return null;
        }

        String apiUrlString = "https://www.googleapis.com/books/v1/volumes?q=isbn:" + isbns[0];
        try{
            HttpURLConnection connection = null;
            // Build Connection.
            try{
                URL url = new URL(apiUrlString);
                connection = (HttpURLConnection) url.openConnection();
                connection.setRequestMethod("GET");
                connection.setReadTimeout(5000); // 5 seconds
                connection.setConnectTimeout(5000); // 5 seconds
            } catch (MalformedURLException e) {
                // Impossible: The only two URLs used in the app are taken from string resources.
                e.printStackTrace();
            } catch (ProtocolException e) {
                // Impossible: "GET" is a perfectly valid request method.
                e.printStackTrace();
            }
            int responseCode = connection.getResponseCode();
            if(responseCode != 200){
                Log.w(getClass().getName(), "GoogleBooksAPI request failed. Response Code: " + responseCode);
                connection.disconnect();
                return null;
            }

            // Read data from response.
            StringBuilder builder = new StringBuilder();
            BufferedReader responseReader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String line = responseReader.readLine();
            while (line != null){
                builder.append(line);
                line = responseReader.readLine();
            }
            String responseString = builder.toString();
            Log.d(getClass().getName(), "Response String: " + responseString);
            JSONObject responseJson = new JSONObject(responseString);
            // Close connection and return response code.
            connection.disconnect();
            return responseJson;
        } catch (SocketTimeoutException e) {
            Log.w(getClass().getName(), "Connection timed out. Returning null");
            return null;
        } catch(IOException e){
            Log.d(getClass().getName(), "IOException when connecting to Google Books API.");
            e.printStackTrace();
            return null;
        } catch (JSONException e) {
            Log.d(getClass().getName(), "JSONException when connecting to Google Books API.");
            e.printStackTrace();
            return null;
        }
    }
    @Override
    protected void onPostExecute(JSONObject responseJson) {
        if(isCancelled()){
            // Request was cancelled due to no network connection.
            showNetworkDialog();
        } else if(responseJson == null){
            showSimpleDialog(getResources().getString(R.string.dialog_null_response));
        }
        else{
            // All went well. Do something with your new JSONObject.
        }
    }
}

protected boolean isNetworkConnected(){

    // Instantiate mConnectivityManager if necessary
    if(mConnectivityManager == null){
        mConnectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
    }
    // Is device connected to the Internet?
    NetworkInfo networkInfo = mConnectivityManager.getActiveNetworkInfo();
    if(networkInfo != null && networkInfo.isConnected()){
        return true;
    } else {
        return false;
    }
}

I've omitted the code for my dialog methods as they are not relevant. Hope this helps.