[Offline pages] Creating BackgroundJobScheduler, which uses JobScheduler

chrome/android/java/src/org/chromium/chrome/browser/offlinepages/BackgroundJobScheduler.java

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.offlinepages;
+
+import android.annotation.TargetApi;
+import android.app.job.JobInfo;
+import android.app.job.JobScheduler;
+import android.content.ComponentName;
+import android.content.Context;
+import android.os.Build;
+import android.os.PersistableBundle;
+
+import java.util.concurrent.TimeUnit;
+
+/**
+ * The background job scheduler class used for scheduling tasks using JobScheduler.
+ */
+@TargetApi(Build.VERSION_CODES.N)
+public class BackgroundJobScheduler extends BackgroundScheduler {
+    public static final int JOB_ID = 774322033;
+
+    public BackgroundJobScheduler(Context context) {
+        super(context);
+    }
+
+    @Override
+    public void cancel() {
+        getJobScheduler().cancel(JOB_ID);
+    }
+
+    @Override
+    protected void scheduleImpl(TriggerConditions triggerConditions, long delayStartSeconds,
+            long executionDeadlineSeconds, boolean overwrite) {
+        if (!overwrite) {
+            JobInfo existingJob = getJobScheduler().getPendingJob(JOB_ID);
+            if (existingJob != null) return;
+        }
+
+        PersistableBundle taskExtras = new PersistableBundle();
+        TaskExtrasPacker.packTimeInBundle(taskExtras);
+        TaskExtrasPacker.packTriggerConditionsInBundle(taskExtras, triggerConditions);
+
+        JobInfo jobInfo =
+                new JobInfo
+                        .Builder(JOB_ID, new ComponentName(
+                                                 getContext(), BackgroundSchedulerJobService.class))
+                        .setMinimumLatency(TimeUnit.SECONDS.toMillis(delayStartSeconds))
+                        .setOverrideDeadline(TimeUnit.SECONDS.toMillis(executionDeadlineSeconds))
+                        .setPersisted(true)  // Across device resets.
+                        .setRequiredNetworkType(triggerConditions.requireUnmeteredNetwork()
+                                        ? JobInfo.NETWORK_TYPE_UNMETERED
+                                        : JobInfo.NETWORK_TYPE_ANY)
+                        .setRequiresCharging(triggerConditions.requirePowerConnected())
+                        .setExtras(taskExtras)
+                        .build();
+
+        getJobScheduler().schedule(jobInfo);
+    }
+
+    private JobScheduler getJobScheduler() {
+        return (JobScheduler) getContext().getSystemService(Context.JOB_SCHEDULER_SERVICE);
+    }
+}