1 /* 2 * Copyright (C) 2014 The Android Open Source Project 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 android.app.job; 18 19 import android.app.Service; 20 import android.content.Intent; 21 import android.os.IBinder; 22 23 /** 24 * <p>Entry point for the callback from the {@link android.app.job.JobScheduler}.</p> 25 * <p>This is the base class that handles asynchronous requests that were previously scheduled. You 26 * are responsible for overriding {@link JobService#onStartJob(JobParameters)}, which is where 27 * you will implement your job logic.</p> 28 * <p>This service executes each incoming job on a {@link android.os.Handler} running on your 29 * application's main thread. This means that you <b>must</b> offload your execution logic to 30 * another thread/handler/{@link android.os.AsyncTask} of your choosing. Not doing so will result 31 * in blocking any future callbacks from the JobManager - specifically 32 * {@link #onStopJob(android.app.job.JobParameters)}, which is meant to inform you that the 33 * scheduling requirements are no longer being met.</p> 34 */ 35 public abstract class JobService extends Service { 36 private static final String TAG = "JobService"; 37 38 /** 39 * Job services must be protected with this permission: 40 * 41 * <pre class="prettyprint"> 42 * <service android:name="MyJobService" 43 * android:permission="android.permission.BIND_JOB_SERVICE" > 44 * ... 45 * </service> 46 * </pre> 47 * 48 * <p>If a job service is declared in the manifest but not protected with this 49 * permission, that service will be ignored by the system. 50 */ 51 public static final String PERMISSION_BIND = 52 "android.permission.BIND_JOB_SERVICE"; 53 54 private JobServiceEngine mEngine; 55 56 /** @hide */ 57 public final IBinder onBind(Intent intent) { 58 if (mEngine == null) { 59 mEngine = new JobServiceEngine(this) { 60 @Override 61 public boolean onStartJob(JobParameters params) { 62 return JobService.this.onStartJob(params); 63 } 64 65 @Override 66 public boolean onStopJob(JobParameters params) { 67 return JobService.this.onStopJob(params); 68 } 69 }; 70 } 71 return mEngine.getBinder(); 72 } 73 74 /** 75 * Call this to inform the JobScheduler that the job has finished its work. When the 76 * system receives this message, it releases the wakelock being held for the job. 77 * <p> 78 * You can request that the job be scheduled again by passing {@code true} as 79 * the <code>wantsReschedule</code> parameter. This will apply back-off policy 80 * for the job; this policy can be adjusted through the 81 * {@link android.app.job.JobInfo.Builder#setBackoffCriteria(long, int)} method 82 * when the job is originally scheduled. The job's initial 83 * requirements are preserved when jobs are rescheduled, regardless of backed-off 84 * policy. 85 * <p class="note"> 86 * A job running while the device is dozing will not be rescheduled with the normal back-off 87 * policy. Instead, the job will be re-added to the queue and executed again during 88 * a future idle maintenance window. 89 * </p> 90 * 91 * @param params The parameters identifying this job, as supplied to 92 * the job in the {@link #onStartJob(JobParameters)} callback. 93 * @param wantsReschedule {@code true} if this job should be rescheduled according 94 * to the back-off criteria specified when it was first scheduled; {@code false} 95 * otherwise. 96 */ 97 public final void jobFinished(JobParameters params, boolean wantsReschedule) { 98 mEngine.jobFinished(params, wantsReschedule); 99 } 100 101 /** 102 * Called to indicate that the job has begun executing. Override this method with the 103 * logic for your job. Like all other component lifecycle callbacks, this method executes 104 * on your application's main thread. 105 * <p> 106 * Return {@code true} from this method if your job needs to continue running. If you 107 * do this, the job remains active until you call 108 * {@link #jobFinished(JobParameters, boolean)} to tell the system that it has completed 109 * its work, or until the job's required constraints are no longer satisfied. For 110 * example, if the job was scheduled using 111 * {@link JobInfo.Builder#setRequiresCharging(boolean) setRequiresCharging(true)}, 112 * it will be immediately halted by the system if the user unplugs the device from power, 113 * the job's {@link #onStopJob(JobParameters)} callback will be invoked, and the app 114 * will be expected to shut down all ongoing work connected with that job. 115 * <p> 116 * The system holds a wakelock on behalf of your app as long as your job is executing. 117 * This wakelock is acquired before this method is invoked, and is not released until either 118 * you call {@link #jobFinished(JobParameters, boolean)}, or after the system invokes 119 * {@link #onStopJob(JobParameters)} to notify your job that it is being shut down 120 * prematurely. 121 * <p> 122 * Returning {@code false} from this method means your job is already finished. The 123 * system's wakelock for the job will be released, and {@link #onStopJob(JobParameters)} 124 * will not be invoked. 125 * 126 * @param params Parameters specifying info about this job, including the optional 127 * extras configured with {@link JobInfo.Builder#setExtras(android.os.PersistableBundle). 128 * This object serves to identify this specific running job instance when calling 129 * {@link #jobFinished(JobParameters, boolean)}. 130 * @return {@code true} if your service will continue running, using a separate thread 131 * when appropriate. {@code false} means that this job has completed its work. 132 */ 133 public abstract boolean onStartJob(JobParameters params); 134 135 /** 136 * This method is called if the system has determined that you must stop execution of your job 137 * even before you've had a chance to call {@link #jobFinished(JobParameters, boolean)}. 138 * 139 * <p>This will happen if the requirements specified at schedule time are no longer met. For 140 * example you may have requested WiFi with 141 * {@link android.app.job.JobInfo.Builder#setRequiredNetworkType(int)}, yet while your 142 * job was executing the user toggled WiFi. Another example is if you had specified 143 * {@link android.app.job.JobInfo.Builder#setRequiresDeviceIdle(boolean)}, and the phone left its 144 * idle maintenance window. You are solely responsible for the behavior of your application 145 * upon receipt of this message; your app will likely start to misbehave if you ignore it. 146 * <p> 147 * Once this method returns, the system releases the wakelock that it is holding on 148 * behalf of the job.</p> 149 * 150 * @param params The parameters identifying this job, as supplied to 151 * the job in the {@link #onStartJob(JobParameters)} callback. 152 * @return {@code true} to indicate to the JobManager whether you'd like to reschedule 153 * this job based on the retry criteria provided at job creation-time; or {@code false} 154 * to end the job entirely. Regardless of the value returned, your job must stop executing. 155 */ 156 public abstract boolean onStopJob(JobParameters params); 157 } 158
