// The connection data
private static final String query = "SELECT Name, Id from Account";
private static final String clientId = "Your salesforce consumer Key";
private static final String clientSecret = "Secret Key";
// THis is meaningless in our context
private static final String redirectUri = "Redirect URI";
//private static final String environment = "https://harishgakhar40-dev-ed.my.salesforce.com";
private static final String environment = "https://login.salesforce.com";
private static String tokenUrl = null;
private static final String username = "salesforce Username";
private static final String password = "salesforce password + security token";
private static String accessToken = null;
private static String instanceUrl = null;
private ArrayAdapter<String> listAdapter;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Create list adapter
    listAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, new ArrayList<String>());
    ((ListView) findViewById(R.id.contacts_list)).setAdapter(listAdapter);
    if (android.os.Build.VERSION.SDK_INT > 9) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }
    // Creating HTTP client
    HttpClient httpClient = new DefaultHttpClient();

    tokenUrl = environment + "/services/oauth2/token?grant_type=password&client_id=" + clientId + "&client_secret=" + clientSecret + "&username=" + username + "&password=" + password;
    HttpPost httpPost = new HttpPost(tokenUrl);

    // Building post parameters
    // key and value pair
    List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(2);

    nameValuePair.add(new BasicNameValuePair("Content-Type", "application/json"));
    try {
        httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));
    } catch (UnsupportedEncodingException e){
        // writing error to Log
        e.printStackTrace();
    }
    JSONTokener tokener;
    String accessToken,instanceURL;
    JSONArray finalResult;
    // Making HTTP Request
    try {

        HttpResponse response = httpClient.execute(httpPost);
        int code = response.getStatusLine().getStatusCode();

        BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
        String json = reader.readLine();
        JSONObject jObj = new JSONObject(json);
        accessToken = jObj.getString("access_token");
        instanceURL = jObj.getString("instance_url");
       getAccountData(accessToken, instanceURL);

    } catch (Exception e) {

        e.getMessage();

    }
}


public  void getAccountData(String access_token, String instance_url) {

    DefaultHttpClient client = new DefaultHttpClient();
    String url = instance_url + "/services/data/v20.0/query/?q=";
    String soqlQuery = "Select Id, Name, BillingStreet, BillingCity, BillingState From Account ";

    try
    {
        url += URLEncoder.encode(soqlQuery, "UTF-8");
    }
    catch(UnsupportedEncodingException e){}

    HttpGet getRequest = new HttpGet(url);
    getRequest.addHeader("Authorization", "OAuth " + access_token);

    try {
        HttpResponse response = client.execute(getRequest);

        String result = EntityUtils.toString(response.getEntity());

        JSONObject object = (JSONObject) new JSONTokener(result).nextValue();
        JSONArray records = object.getJSONArray("records");

        listAdapter.clear();
        for (int i=0;i<records.length();i++) {


            JSONObject record = (JSONObject) records.get(i);
            String accountName = record.getString("Name");
            Log.v("accountName---- ","accountName ---- "+accountName);
            listAdapter.add(accountName);

        }

    } catch (Exception e) {
        e.printStackTrace();
    }
}