Java tutorial
/* * This file is part of Prepay Credit for Android * * Copyright 2014 Damien O'Reilly * * Prepay Credit for Android is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * Prepay Credit for Android is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Prepay Credit for Android. If not, see <http://www.gnu.org/licenses/>. * * Report bugs or new features at: https://github.com/DamienOReilly/PrepayCredit * Contact the author at: damienreilly@gmail.com */ package damo.three.ie.prepay; import android.app.AlarmManager; import android.app.IntentService; import android.app.PendingIntent; import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.preference.PreferenceManager; import android.util.Log; import damo.three.ie.prepayusage.BasicUsageItem; import damo.three.ie.prepayusage.UsageItem; import damo.three.ie.util.JSONUtils; import damo.three.ie.util.UsageUtils; import org.joda.time.DateTime; import org.json.JSONArray; import java.util.Calendar; import java.util.List; /** * Service responsible for the background fetch of user usages. Works silently. * * @author Damien O'Reilly */ public class UpdateService extends IntentService { public UpdateService() { super("PrepayUpdateService"); } @Override protected void onHandleIntent(Intent intent) { Context context = getApplicationContext(); try { Log.d(Constants.TAG, "Fetching usages from service."); UsageFetcher usageFetcher = new UsageFetcher(context, true); JSONArray usages = usageFetcher.getUsages(); SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(getApplicationContext()); SharedPreferences sharedUsagePref = context.getSharedPreferences("damo.three.ie.previous_usage", Context.MODE_PRIVATE); SharedPreferences.Editor editor = sharedUsagePref.edit(); editor.putLong("last_refreshed_milliseconds", new DateTime().getMillis()); editor.putString("usage_info", usages.toString()); editor.commit(); // Register alarms for newly refreshed usages in background boolean notificationsEnabled = sharedPref.getBoolean("notification", true); List<UsageItem> usageItems = JSONUtils.jsonToUsageItems(usages); List<BasicUsageItem> basicUsageItems = UsageUtils.getAllBasicItems(usageItems); UsageUtils.registerInternetExpireAlarm(context, basicUsageItems, notificationsEnabled, true); } catch (Exception e) { // Try again at 7pm, unless its past 7pm. Then forget and let tomorrow's alarm do the updating. // Still trying to decide if I need a more robust retry mechanism. Log.d(Constants.TAG, "Caught exception: " + e.getLocalizedMessage()); Calendar calendar = Calendar.getInstance(); if (calendar.get(Calendar.HOUR_OF_DAY) < Constants.HOUR_TO_RETRY) { Log.d(Constants.TAG, "Scheduling a re-try for 7pm"); calendar.set(Calendar.HOUR_OF_DAY, Constants.HOUR_TO_RETRY); calendar.set(Calendar.MINUTE, 0); calendar.set(Calendar.SECOND, 0); Intent receiver = new Intent(context, UpdateReceiver.class); AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); // Using different request code to 0 so it won't conflict with other alarm below. PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 3, receiver, PendingIntent.FLAG_UPDATE_CURRENT); // Keeping efficiency in mind: // http://developer.android.com/reference/android/app/AlarmManager.html#ELAPSED_REALTIME am.set(AlarmManager.RTC, calendar.getTimeInMillis(), pendingIntent); } } finally { Log.d(Constants.TAG, "Finish UpdateService"); UpdateReceiver.completeWakefulIntent(intent); } } }