| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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.android.tv.util; |
| |
| import android.content.Context; |
| import android.content.SharedPreferences; |
| import android.os.AsyncTask; |
| import android.os.Handler; |
| import android.support.annotation.WorkerThread; |
| import android.util.Log; |
| import com.android.tv.common.SoftPreconditions; |
| import com.android.tv.common.util.SharedPreferencesUtils; |
| import java.util.Date; |
| |
| /** |
| * Repeatedly executes a {@link Runnable}. |
| * |
| * <p>The next execution time is saved to a {@link SharedPreferences}, and used on the next start. |
| * The given {@link Runnable} will run in the main thread. |
| */ |
| public final class RecurringRunner { |
| private static final String TAG = "RecurringRunner"; |
| private static final boolean DEBUG = false; |
| |
| private final Handler mHandler; |
| private final long mIntervalMs; |
| private final Runnable mRunnable; |
| private final Runnable mOnStopRunnable; |
| private final Context mContext; |
| private final String mName; |
| private boolean mRunning; |
| |
| public RecurringRunner( |
| Context context, long intervalMs, Runnable runnable, Runnable onStopRunnable) { |
| mContext = context.getApplicationContext(); |
| mRunnable = runnable; |
| mOnStopRunnable = onStopRunnable; |
| mIntervalMs = intervalMs; |
| mName = runnable.getClass().getCanonicalName(); |
| if (DEBUG) Log.i(TAG, " Delaying " + mName + " " + (intervalMs / 1000.0) + " seconds"); |
| mHandler = new Handler(mContext.getMainLooper()); |
| } |
| |
| public void start(boolean resetNextRunTime) { |
| SoftPreconditions.checkState(!mRunning, TAG, mName + " start is called twice."); |
| if (mRunning) { |
| return; |
| } |
| mRunning = true; |
| if (resetNextRunTime) { |
| resetNextRunTime(); |
| } |
| new AsyncTask<Void, Void, Long>() { |
| @Override |
| protected Long doInBackground(Void... params) { |
| return getNextRunTime(); |
| } |
| |
| @Override |
| protected void onPostExecute(Long nextRunTime) { |
| postAt(nextRunTime); |
| } |
| }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR); |
| } |
| |
| public void start() { |
| start(false); |
| } |
| |
| public void stop() { |
| mRunning = false; |
| mHandler.removeCallbacksAndMessages(null); |
| if (mOnStopRunnable != null) { |
| mOnStopRunnable.run(); |
| } |
| } |
| |
| private void postAt(long next) { |
| if (!mRunning) { |
| return; |
| } |
| long now = System.currentTimeMillis(); |
| // Run it anyways even if it is in the past |
| if (DEBUG) Log.i(TAG, "Next run of " + mName + " at " + new Date(next)); |
| long delay = Math.max(next - now, 0); |
| boolean posted = |
| mHandler.postDelayed( |
| new Runnable() { |
| @Override |
| public void run() { |
| try { |
| if (DEBUG) Log.i(TAG, "Starting " + mName); |
| mRunnable.run(); |
| } catch (Exception e) { |
| Log.w(TAG, "Error running " + mName, e); |
| } |
| postAt(resetNextRunTime()); |
| } |
| }, |
| delay); |
| if (!posted) { |
| Log.w(TAG, "Scheduling a future run of " + mName + " at " + new Date(next) + "failed"); |
| } |
| if (DEBUG) Log.i(TAG, "Actual delay of " + mName + " is " + (delay / 1000.0) + " seconds."); |
| } |
| |
| private SharedPreferences getSharedPreferences() { |
| return mContext.getSharedPreferences( |
| SharedPreferencesUtils.SHARED_PREF_RECURRING_RUNNER, Context.MODE_PRIVATE); |
| } |
| |
| @WorkerThread |
| private long getNextRunTime() { |
| // The access to SharedPreferences is done by an AsyncTask thread because |
| // SharedPreferences reads to disk at first time. |
| long next = getSharedPreferences().getLong(mName, System.currentTimeMillis()); |
| if (next > System.currentTimeMillis() + mIntervalMs) { |
| next = resetNextRunTime(); |
| } |
| return next; |
| } |
| |
| private long resetNextRunTime() { |
| long next = System.currentTimeMillis() + mIntervalMs; |
| getSharedPreferences().edit().putLong(mName, next).apply(); |
| return next; |
| } |
| } |