1 /* 2 * Copyright (C) 2014 Google Inc. All Rights Reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.example.android.wearable.speedtracker; 18 19 import com.example.android.wearable.speedtracker.common.LocationEntry; 20 import com.example.android.wearable.speedtracker.common.Utils; 21 import com.example.android.wearable.speedtracker.db.LocationDbHelper; 22 23 import java.util.ArrayList; 24 import java.util.Calendar; 25 import java.util.HashMap; 26 import java.util.List; 27 import java.util.Map; 28 29 /** 30 * A class that wraps database access and provides a cache for various GPS data. 31 */ 32 public class LocationDataManager { 33 34 private final Map<String, List<LocationEntry>> mPointsMap = 35 new HashMap<String, List<LocationEntry>>(); 36 37 private LocationDbHelper mDbHelper; 38 39 public LocationDataManager(LocationDbHelper dbHelper) { 40 mDbHelper = dbHelper; 41 } 42 43 /** 44 * Returns a list of {@link com.example.android.wearable.speedtracker.common.LocationEntry} 45 * objects for the day that the {@link java.util.Calendar} object points at. Internally it uses 46 * a cache to speed up subsequent calls. If there is no cached value, it gets the result from 47 * the database. 48 */ 49 public final List<LocationEntry> getPoints(Calendar calendar) { 50 String day = Utils.getHashedDay(calendar); 51 synchronized (mPointsMap) { 52 if (mPointsMap.get(day) == null) { 53 // there is no cache for this day, so lets get it from DB 54 List<LocationEntry> points = mDbHelper.read(calendar); 55 mPointsMap.put(day, points); 56 } 57 } 58 return mPointsMap.get(day); 59 } 60 61 /** 62 * Clears the data for the day that the {@link java.util.Calendar} object falls on. This method 63 * removes the entries from the database and updates the cache accordingly. 64 */ 65 public final int clearPoints(Calendar calendar) { 66 synchronized (mPointsMap) { 67 String day = Utils.getHashedDay(calendar); 68 mPointsMap.remove(day); 69 return mDbHelper.delete(day); 70 } 71 } 72 73 /** 74 * Adds a {@link com.example.android.wearable.speedtracker.common.LocationEntry} point to the 75 * database and cache if it is a new point. 76 */ 77 public final void addPoint(LocationEntry entry) { 78 synchronized (mPointsMap) { 79 List<LocationEntry> points = getPoints(entry.calendar); 80 if (points == null || points.isEmpty()) { 81 mDbHelper.insert(entry); 82 if (points == null) { 83 points = new ArrayList<LocationEntry>(); 84 } 85 points.add(entry); 86 mPointsMap.put(entry.day, points); 87 } else { 88 if (!points.contains(entry)) { 89 mDbHelper.insert(entry); 90 points.add(entry); 91 } 92 } 93 } 94 } 95 } 96
