Java tutorial
/* * Copyright 2012 Google Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.technion.studybuddy.GCM; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Random; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.message.BasicNameValuePair; import android.accounts.AuthenticatorException; import android.accounts.OperationCanceledException; import android.app.Activity; import android.content.Context; import android.net.http.AndroidHttpClient; import android.os.Build; import android.provider.Settings.Secure; import android.util.Log; import com.google.android.gcm.GCMRegistrar; import com.technion.studybuddy.exceptions.AccessException; import com.technion.studybuddy.utils.Constants; /** * Helper class used to communicate with the demo server. */ public final class ServerUtilities { // private static String name; private static Activity activity; private static final int BACKOFF_MILLI_SECONDS = 2000; private static final int MAX_ATTEMPTS = 5; private static final Random random = new Random(); /** * @param prefs * @return */ public static boolean isRegistered(Context context) { return context.getSharedPreferences(Constants.PrefsContext, 0).getBoolean(Constants.IS_REGISTERED, false); } private static String capitalize(String s) { if (s == null || s.length() == 0) return ""; char first = s.charAt(0); if (Character.isUpperCase(first)) return s; else return Character.toUpperCase(first) + s.substring(1); } public static String getDeviceName() { String manufacturer = Build.MANUFACTURER; String model = Build.MODEL; if (model.startsWith(manufacturer)) return capitalize(model); else return capitalize(manufacturer) + " " + model; } /** * Issue a POST request to the server. * * @param endpoint * POST address. * @param params * request parameters. * * @throws IOException * propagated from POST. */ public static void post(String endpoint, String regID) throws IOException { AndroidHttpClient client = AndroidHttpClient.newInstance("GetAuthCookieClient", ServerUtilities.activity); try { GoogleHttpContext httpContext = ServerUtilities.getContext(ServerUtilities.activity, Constants.SERVER_URL); HttpPost httpPost = new HttpPost(endpoint); List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(); nameValuePairs.add(new BasicNameValuePair("regid", regID)); nameValuePairs.add(new BasicNameValuePair("model", getDeviceName())); nameValuePairs.add(new BasicNameValuePair("deviceID", Secure.getString(ServerUtilities.activity.getContentResolver(), Secure.ANDROID_ID))); httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs)); HttpResponse res = client.execute(httpPost, httpContext); res.toString(); } catch (NotRegisteredException e) { // cannot be registered with play registration e.printStackTrace(); } finally { client.close(); } } /** * Register this account/device pair within the server. * * @return whether the registration succeeded or not. */ public static boolean register(final Context context, final String regId) { CommonUtilities.getAccountName(context); Log.i(CommonUtilities.TAG, "registering device (regId = " + regId + ")"); String serverUrl = Constants.SERVER_URL + "/register"; Map<String, String> params = new HashMap<String, String>(); params.put("regId", regId); long backoff = ServerUtilities.BACKOFF_MILLI_SECONDS + ServerUtilities.random.nextInt(1000); // Once GCM returns a registration id, we need to register it in the // demo server. As the server might be down, we will retry it a couple // times. for (int i = 1; i <= ServerUtilities.MAX_ATTEMPTS; i++) { Log.d(CommonUtilities.TAG, "Attempt #" + i + " to register"); try { post("http://" + serverUrl, regId); GCMRegistrar.setRegisteredOnServer(context, true); // TODO update server with regid return true; } catch (IOException e) { // Here we are simplifying and retrying on any error; in a real // application, it should retry only on unrecoverable errors // (like HTTP error code 503). Log.e(CommonUtilities.TAG, "Failed to register on attempt " + i, e); if (i == ServerUtilities.MAX_ATTEMPTS) break; try { Log.d(CommonUtilities.TAG, "Sleeping for " + backoff + " ms before retry"); Thread.sleep(backoff); } catch (InterruptedException e1) { // Activity finished before we complete - exit. Log.d(CommonUtilities.TAG, "Thread interrupted: abort remaining retries!"); Thread.currentThread().interrupt(); return false; } // increase backoff exponentially backoff *= 2; } } String message = "could not register check connection"; CommonUtilities.displayMessage(context, message); return false; } public static void registerToServer(Activity activity) { String regid; setActivity(activity); // if ("".equals(accountName)) // { // // Toast.makeText(activity, "please choose account to sign with", // // Toast.LENGTH_LONG).show(); // // Intent intent = new Intent(activity, StbSettingsActivity.class); // // activity.startActivity(intent); // String email = // return; // // } regid = CommonUtilities.register(activity); if (regid == null) GCMRegistrar.register(activity, CommonUtilities.SENDER_ID); } /** * @param activity * the activity to set */ public static synchronized void setActivity(Activity activity) { ServerUtilities.activity = activity; } /** * Unregister this account/device pair within the server. */ public static void unregister(final Context context, final String regId) { Log.i(CommonUtilities.TAG, "unregistering device (regId = " + regId + ")"); new Thread(new Runnable() { @Override public void run() { try { final String serverUrl = Constants.SERVER_URL + "/unregister"; post("http://" + serverUrl, regId); GCMRegistrar.setRegisteredOnServer(context, false); String message = "unregistering"; CommonUtilities.displayMessage(context, message); } catch (IOException e) { // At this point the device is unregistered from GCM, but // still // registered in the server. // We could try to unregister again, but it is not // necessary: // if the server tries to send a message to the device, it // will get // a "NotRegistered" error message and should unregister the // device. String message = e.getMessage(); CommonUtilities.displayMessage(context, message); } } }).start(); } public static GoogleHttpContext getContext(Context activity, String baseUrl) throws NotRegisteredException { if (!isRegistered(activity)) throw new NotRegisteredException(); try { return Constants.debug ? new GoogleHttpContextDev(activity, baseUrl) : new GoogleHttpContextProduction(activity, baseUrl); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (OperationCanceledException e) { e.printStackTrace(); } catch (AuthenticatorException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (AccessException e) { e.printStackTrace(); } return null; } }