MainActivity.java

package com.hmkcode.android;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Iterator;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.app.Activity;

public class MainActivity extends Activity {

	EditText etResponse;
	TextView tvIsConnected;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		
		// get reference to the views
		etResponse = (EditText) findViewById(R.id.etResponse);
		tvIsConnected = (TextView) findViewById(R.id.tvIsConnected);
		
		// check if you are connected or not
		if(isConnected()){
			tvIsConnected.setBackgroundColor(0xFF00CC00);
			tvIsConnected.setText("You are conncted");
        }
		else{
			tvIsConnected.setText("You are NOT conncted");
		}
			
		
		// call AsynTask to perform network operation on separate thread
		new HttpAsyncTask().execute("http://hmkcode.appspot.com/rest/controller/get.json");
	}

	public static String GET(String url){
		InputStream inputStream = null;
		String result = "";
		try {
			
			// create HttpClient
			HttpClient httpclient = new DefaultHttpClient();
			
			// make GET request to the given URL
			HttpResponse httpResponse = httpclient.execute(new HttpGet(url));
			
			// receive response as inputStream
			inputStream = httpResponse.getEntity().getContent();
			
			// convert inputstream to string
			if(inputStream != null)
				result = convertInputStreamToString(inputStream);
			else
				result = "Did not work!";
		
		} catch (Exception e) {
			Log.d("InputStream", e.getLocalizedMessage());
		}
		
		return result;
	}
	
    private static String convertInputStreamToString(InputStream inputStream) throws IOException{
        BufferedReader bufferedReader = new BufferedReader( new InputStreamReader(inputStream));
        String line = "";
        String result = "";
        while((line = bufferedReader.readLine()) != null)
            result += line;
        
        inputStream.close();
        return result;
        
    }
	
    public boolean isConnected(){
    	ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE);
    	    NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
    	    if (networkInfo != null && networkInfo.isConnected()) 
    	    	return true;
    	    else
    	    	return false;	
    }
    private class HttpAsyncTask extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... urls) {
              
            return GET(urls[0]);
        }
        // onPostExecute displays the results of the AsyncTask.
        @Override
        protected void onPostExecute(String result) {
        	Toast.makeText(getBaseContext(), "Received!", Toast.LENGTH_LONG).show();
        	try {
				JSONObject json = new JSONObject(result);
				
				String str = "";
				
				JSONArray articles = json.getJSONArray("articleList");
				str += "articles length = "+json.getJSONArray("articleList").length();
				str += "\n--------\n";
				str += "names: "+articles.getJSONObject(0).names();
				str += "\n--------\n";
				str += "url: "+articles.getJSONObject(0).getString("url");
				
				etResponse.setText(str);
	        	//etResponse.setText(json.toString(1));

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