xref: /frameworks/base/apex/jobscheduler/framework/java/android/app/AlarmManager.java

/*
 * Copyright (C) 2007 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 android.app;

import android.Manifest;
import android.annotation.IntDef;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.RequiresPermission;
import android.annotation.SdkConstant;
import android.annotation.SdkConstant.SdkConstantType;
import android.annotation.SystemApi;
import android.annotation.SystemService;
import android.annotation.TestApi;
import android.compat.annotation.ChangeId;
import android.compat.annotation.Disabled;
import android.compat.annotation.EnabledSince;
import android.compat.annotation.UnsupportedAppUsage;
import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.os.Handler;
import android.os.HandlerExecutor;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.Process;
import android.os.RemoteException;
import android.os.UserHandle;
import android.os.WorkSource;
import android.text.TextUtils;
import android.util.Log;
import android.util.proto.ProtoOutputStream;

import com.android.i18n.timezone.ZoneInfoDb;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.ref.WeakReference;
import java.util.Objects;
import java.util.WeakHashMap;
import java.util.concurrent.Executor;

/**
 * This class provides access to the system alarm services.  These allow you
 * to schedule your application to be run at some point in the future.  When
 * an alarm goes off, the {@link Intent} that had been registered for it
 * is broadcast by the system, automatically starting the target application
 * if it is not already running.  Registered alarms are retained while the
 * device is asleep (and can optionally wake the device up if they go off
 * during that time), but will be cleared if it is turned off and rebooted.
 *
 * <p>The Alarm Manager holds a CPU wake lock as long as the alarm receiver's
 * onReceive() method is executing. This guarantees that the phone will not sleep
 * until you have finished handling the broadcast. Once onReceive() returns, the
 * Alarm Manager releases this wake lock. This means that the phone will in some
 * cases sleep as soon as your onReceive() method completes.  If your alarm receiver
 * called {@link android.content.Context#startService Context.startService()}, it
 * is possible that the phone will sleep before the requested service is launched.
 * To prevent this, your BroadcastReceiver and Service will need to implement a
 * separate wake lock policy to ensure that the phone continues running until the
 * service becomes available.
 *
 * <p><b>Note: The Alarm Manager is intended for cases where you want to have
 * your application code run at a specific time, even if your application is
 * not currently running.  For normal timing operations (ticks, timeouts,
 * etc) it is easier and much more efficient to use
 * {@link android.os.Handler}.</b>
 *
 * <p class="caution"><strong>Note:</strong> Beginning with API 19
 * ({@link android.os.Build.VERSION_CODES#KITKAT}) alarm delivery is inexact:
 * the OS will shift alarms in order to minimize wakeups and battery use.  There are
 * new APIs to support applications which need strict delivery guarantees; see
 * {@link #setWindow(int, long, long, PendingIntent)} and
 * {@link #setExact(int, long, PendingIntent)}.  Applications whose {@code targetSdkVersion}
 * is earlier than API 19 will continue to see the previous behavior in which all
 * alarms are delivered exactly when requested.
 */
@SystemService(Context.ALARM_SERVICE)
public class AlarmManager {
    private static final String TAG = "AlarmManager";

    /**
     * Prefix used by {{@link #makeTag(long, WorkSource)}} to make a tag on behalf of the caller
     * when the {@link #set(int, long, long, long, OnAlarmListener, Handler, WorkSource)} API is
     * used. This prefix is a unique sequence of characters to differentiate with other tags that
     * apps may provide to other APIs that accept a listener callback.
     */
    private static final String GENERATED_TAG_PREFIX = "$android.alarm.generated";

    /** @hide */
    @IntDef(prefix = { "RTC", "ELAPSED" }, value = {
            RTC_WAKEUP,
            RTC,
            ELAPSED_REALTIME_WAKEUP,
            ELAPSED_REALTIME,
    })
    @Retention(RetentionPolicy.SOURCE)
    public @interface AlarmType {}

    /**
     * Alarm time in {@link System#currentTimeMillis System.currentTimeMillis()}
     * (wall clock time in UTC), which will wake up the device when
     * it goes off.
     */
    public static final int RTC_WAKEUP = 0;
    /**
     * Alarm time in {@link System#currentTimeMillis System.currentTimeMillis()}
     * (wall clock time in UTC).  This alarm does not wake the
     * device up; if it goes off while the device is asleep, it will not be
     * delivered until the next time the device wakes up.
     */
    public static final int RTC = 1;
    /**
     * Alarm time in {@link android.os.SystemClock#elapsedRealtime
     * SystemClock.elapsedRealtime()} (time since boot, including sleep),
     * which will wake up the device when it goes off.
     */
    public static final int ELAPSED_REALTIME_WAKEUP = 2;
    /**
     * Alarm time in {@link android.os.SystemClock#elapsedRealtime
     * SystemClock.elapsedRealtime()} (time since boot, including sleep).
     * This alarm does not wake the device up; if it goes off while the device
     * is asleep, it will not be delivered until the next time the device
     * wakes up.
     */
    public static final int ELAPSED_REALTIME = 3;

    /**
     * Broadcast Action: Sent after the value returned by
     * {@link #getNextAlarmClock()} has changed.
     *
     * <p class="note">This is a protected intent that can only be sent by the system.
     * It is only sent to registered receivers.</p>
     */
    @SdkConstant(SdkConstant.SdkConstantType.BROADCAST_INTENT_ACTION)
    public static final String ACTION_NEXT_ALARM_CLOCK_CHANGED =
            "android.app.action.NEXT_ALARM_CLOCK_CHANGED";

    /**
     * Broadcast Action: An app is granted the
     * {@link android.Manifest.permission#SCHEDULE_EXACT_ALARM} permission.
     *
     * <p>When the user revokes the {@link android.Manifest.permission#SCHEDULE_EXACT_ALARM}
     * permission, all alarms scheduled with
     * {@link #setExact}, {@link #setExactAndAllowWhileIdle} and
     * {@link #setAlarmClock(AlarmClockInfo, PendingIntent)} will be deleted.
     *
     * <p>When the user grants the {@link android.Manifest.permission#SCHEDULE_EXACT_ALARM},
     * this broadcast will be sent. Applications can reschedule all the necessary alarms when
     * receiving it.
     *
     * <p>This broadcast will <em>not</em> be sent when the user revokes the permission.
     *
     * <p><em>Note:</em>
     * Applications are still required to check {@link #canScheduleExactAlarms()}
     * before using the above APIs after receiving this broadcast,
     * because it's possible that the permission is already revoked again by the time
     * applications receive this broadcast.
     *
     * <p>This broadcast will be sent to both runtime receivers and manifest receivers.
     *
     * <p>This broadcast is sent as a foreground broadcast.
     * See {@link android.content.Intent#FLAG_RECEIVER_FOREGROUND}.
     *
     * <p>When an application receives this broadcast, it's allowed to start a foreground service.
     */
    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
    public static final String ACTION_SCHEDULE_EXACT_ALARM_PERMISSION_STATE_CHANGED =
            "android.app.action.SCHEDULE_EXACT_ALARM_PERMISSION_STATE_CHANGED";

    /** @hide */
    @UnsupportedAppUsage
    public static final long WINDOW_EXACT = 0;
    /** @hide */
    @UnsupportedAppUsage
    public static final long WINDOW_HEURISTIC = -1;

    /**
     * Flag for alarms: this is to be a stand-alone alarm, that should not be batched with
     * other alarms.
     * @hide
     */
    @UnsupportedAppUsage
    public static final int FLAG_STANDALONE = 1<<0;

    /**
     * Flag for alarms: this alarm would like to wake the device even if it is idle.  This
     * is, for example, an alarm for an alarm clock.
     * @hide
     */
    @UnsupportedAppUsage
    public static final int FLAG_WAKE_FROM_IDLE = 1<<1;

    /**
     * Flag for alarms: this alarm would like to still execute even if the device is
     * idle.  This won't bring the device out of idle, just allow this specific alarm to
     * run.  Note that this means the actual time this alarm goes off can be inconsistent
     * with the time of non-allow-while-idle alarms (it could go earlier than the time
     * requested by another alarm).
     *
     * @hide
     */
    public static final int FLAG_ALLOW_WHILE_IDLE = 1<<2;

    /**
     * Flag for alarms: same as {@link #FLAG_ALLOW_WHILE_IDLE}, but doesn't have restrictions
     * on how frequently it can be scheduled.  Only available (and automatically applied) to
     * system alarms.
     *
     * <p>Note that alarms set with a {@link WorkSource} <b>do not</b> get this flag.
     *
     * @hide
     */
    @UnsupportedAppUsage
    public static final int FLAG_ALLOW_WHILE_IDLE_UNRESTRICTED = 1<<3;

    /**
     * Flag for alarms: this alarm marks the point where we would like to come out of idle
     * mode.  It may be moved by the alarm manager to match the first wake-from-idle alarm.
     * Scheduling an alarm with this flag puts the alarm manager in to idle mode, where it
     * avoids scheduling any further alarms until the marker alarm is executed.
     * @hide
     */
    @UnsupportedAppUsage
    public static final int FLAG_IDLE_UNTIL = 1<<4;

    /**
     * Flag for alarms: Used to provide backwards compatibility for apps with targetSdkVersion less
     * than {@link Build.VERSION_CODES#S}
     * @hide
     */
    public static final int FLAG_ALLOW_WHILE_IDLE_COMPAT = 1 << 5;

    /**
     * Flag for alarms: Used to mark prioritized alarms. These alarms will get to execute while idle
     * and can be sent separately from other alarms that may be already due at the time.
     * These alarms can be set via
     * {@link #setPrioritized(int, long, long, String, Executor, OnAlarmListener)}
     * @hide
     */
    public static final int FLAG_PRIORITIZE = 1 << 6;

    /**
     * For apps targeting {@link Build.VERSION_CODES#S} or above, any APIs setting exact alarms,
     * e.g. {@link #setExact(int, long, PendingIntent)},
     * {@link #setAlarmClock(AlarmClockInfo, PendingIntent)} and others will require holding a new
     * permission {@link Manifest.permission#SCHEDULE_EXACT_ALARM}
     *
     * @hide
     */
    @ChangeId
    @EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)
    public static final long REQUIRE_EXACT_ALARM_PERMISSION = 171306433L;

    /**
     * For apps targeting {@link Build.VERSION_CODES#S} or above, all inexact alarms will require
     * to have a minimum window size, expected to be on the order of a few minutes.
     *
     * Practically, any alarms requiring smaller windows are the same as exact alarms and should use
     * the corresponding APIs provided, like {@link #setExact(int, long, PendingIntent)}, et al.
     *
     * Inexact alarm with shorter windows specified will have their windows elongated by the system.
     *
     * @hide
     */
    @ChangeId
    @EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)
    public static final long ENFORCE_MINIMUM_WINDOW_ON_INEXACT_ALARMS = 185199076L;

    /**
     * For apps targeting {@link Build.VERSION_CODES#TIRAMISU} or above, certain kinds of apps can
     * use {@link Manifest.permission#USE_EXACT_ALARM} to schedule exact alarms.
     *
     * @hide
     */
    @ChangeId
    @EnabledSince(targetSdkVersion = Build.VERSION_CODES.TIRAMISU)
    public static final long ENABLE_USE_EXACT_ALARM = 218533173L;

    /**
     * The permission {@link Manifest.permission#SCHEDULE_EXACT_ALARM} will be denied, unless the
     * user explicitly allows it from Settings.
     *
     * TODO (b/226439802): Either enable it in the next SDK or replace it with a better alternative.
     * @hide
     */
    @ChangeId
    @Disabled
    public static final long SCHEDULE_EXACT_ALARM_DENIED_BY_DEFAULT = 226439802L;

    @UnsupportedAppUsage
    private final IAlarmManager mService;
    private final Context mContext;
    private final String mPackageName;
    private final boolean mAlwaysExact;
    private final int mTargetSdkVersion;
    private final Handler mMainThreadHandler;

    /**
     * Direct-notification alarms: the requester must be running continuously from the
     * time the alarm is set to the time it is delivered, or delivery will fail.  Only
     * one-shot alarms can be set using this mechanism, not repeating alarms.
     */
    public interface OnAlarmListener {
        /**
         * Callback method that is invoked by the system when the alarm time is reached.
         */
        public void onAlarm();
    }

    final class ListenerWrapper extends IAlarmListener.Stub implements Runnable {
        final OnAlarmListener mListener;
        Executor mExecutor;
        IAlarmCompleteListener mCompletion;

        public ListenerWrapper(OnAlarmListener listener) {
            mListener = listener;
        }

        void setExecutor(Executor e) {
            mExecutor = e;
        }

        public void cancel() {
            try {
                mService.remove(null, this);
            } catch (RemoteException ex) {
                throw ex.rethrowFromSystemServer();
            }
        }

        @Override
        public void doAlarm(IAlarmCompleteListener alarmManager) {
            mCompletion = alarmManager;

            mExecutor.execute(this);
        }

        @Override
        public void run() {
            // Now deliver it to the app
            try {
                mListener.onAlarm();
            } finally {
                // No catch -- make sure to report completion to the system process,
                // but continue to allow the exception to crash the app.

                try {
                    mCompletion.alarmComplete(this);
                } catch (Exception e) {
                    Log.e(TAG, "Unable to report completion to Alarm Manager!", e);
                }
            }
        }
    }

    /**
     * Tracking of the OnAlarmListener -> ListenerWrapper mapping, for cancel() support.
     * An entry is guaranteed to stay in this map as long as its ListenerWrapper is held by the
     * server.
     *
     * <p>Access is synchronized on the AlarmManager class object.
     */
    private static WeakHashMap<OnAlarmListener, WeakReference<ListenerWrapper>> sWrappers;

    /**
     * package private on purpose
     */
    AlarmManager(IAlarmManager service, Context ctx) {
        mService = service;

        mContext = ctx;
        mPackageName = ctx.getPackageName();
        mTargetSdkVersion = ctx.getApplicationInfo().targetSdkVersion;
        mAlwaysExact = (mTargetSdkVersion < Build.VERSION_CODES.KITKAT);
        mMainThreadHandler = new Handler(ctx.getMainLooper());
    }

    private long legacyExactLength() {
        return (mAlwaysExact ? WINDOW_EXACT : WINDOW_HEURISTIC);
    }

    /**
     * <p>Schedule an alarm.  <b>Note: for timing operations (ticks, timeouts,
     * etc) it is easier and much more efficient to use {@link android.os.Handler}.</b>
     * If there is already an alarm scheduled for the same IntentSender, that previous
     * alarm will first be canceled.
     *
     * <p>If the stated trigger time is in the past, the alarm will be triggered
     * immediately.  If there is already an alarm for this Intent
     * scheduled (with the equality of two intents being defined by
     * {@link Intent#filterEquals}), then it will be removed and replaced by
     * this one.
     *
     * <p>
     * The alarm is an Intent broadcast that goes to a broadcast receiver that
     * you registered with {@link android.content.Context#registerReceiver}
     * or through the &lt;receiver&gt; tag in an AndroidManifest.xml file.
     *
     * <p>
     * Alarm intents are delivered with a data extra of type int called
     * {@link Intent#EXTRA_ALARM_COUNT Intent.EXTRA_ALARM_COUNT} that indicates
     * how many past alarm events have been accumulated into this intent
     * broadcast.  Recurring alarms that have gone undelivered because the
     * phone was asleep may have a count greater than one when delivered.
     *
     * <div class="note">
     * <p>
     * <b>Note:</b> Beginning in API 19, the trigger time passed to this method
     * is treated as inexact: the alarm will not be delivered before this time, but
     * may be deferred and delivered some time later.  The OS will use
     * this policy in order to "batch" alarms together across the entire system,
     * minimizing the number of times the device needs to "wake up" and minimizing
     * battery use.  In general, alarms scheduled in the near future will not
     * be deferred as long as alarms scheduled far in the future.
     *
     * <p>
     * With the new batching policy, delivery ordering guarantees are not as
     * strong as they were previously.  If the application sets multiple alarms,
     * it is possible that these alarms' <em>actual</em> delivery ordering may not match
     * the order of their <em>requested</em> delivery times.  If your application has
     * strong ordering requirements there are other APIs that you can use to get
     * the necessary behavior; see {@link #setWindow(int, long, long, PendingIntent)}
     * and {@link #setExact(int, long, PendingIntent)}.
     *
     * <p>
     * Applications whose {@code targetSdkVersion} is before API 19 will
     * continue to get the previous alarm behavior: all of their scheduled alarms
     * will be treated as exact.
     * </div>
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should go
     * off, using the appropriate clock (depending on the alarm type).
     * @param operation Action to perform when the alarm goes off;
     * typically comes from {@link PendingIntent#getBroadcast
     * IntentSender.getBroadcast()}.
     *
     * @see android.os.Handler
     * @see #setExact
     * @see #setRepeating
     * @see #setWindow
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     */
    public void set(@AlarmType int type, long triggerAtMillis, PendingIntent operation) {
        setImpl(type, triggerAtMillis, legacyExactLength(), 0, 0, operation, null, null,
                (Handler) null, null, null);
    }

    /**
     * Direct callback version of {@link #set(int, long, PendingIntent)}.  Rather than
     * supplying a PendingIntent to be sent when the alarm time is reached, this variant
     * supplies an {@link OnAlarmListener} instance that will be invoked at that time.
     * <p>
     * The OnAlarmListener's {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     * invoked via the specified target Handler, or on the application's main looper
     * if {@code null} is passed as the {@code targetHandler} parameter.
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should go
     *         off, using the appropriate clock (depending on the alarm type).
     * @param tag string describing the alarm, used for logging and battery-use
     *         attribution
     * @param listener {@link OnAlarmListener} instance whose
     *         {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     *         called when the alarm time is reached.  A given OnAlarmListener instance can
     *         only be the target of a single pending alarm, just as a given PendingIntent
     *         can only be used with one alarm at a time.
     * @param targetHandler {@link Handler} on which to execute the listener's onAlarm()
     *         callback, or {@code null} to run that callback on the main looper.
     */
    public void set(@AlarmType int type, long triggerAtMillis, String tag, OnAlarmListener listener,
            Handler targetHandler) {
        setImpl(type, triggerAtMillis, legacyExactLength(), 0, 0, null, listener, tag,
                targetHandler, null, null);
    }

    /**
     * Schedule a repeating alarm.  <b>Note: for timing operations (ticks,
     * timeouts, etc) it is easier and much more efficient to use
     * {@link android.os.Handler}.</b>  If there is already an alarm scheduled
     * for the same IntentSender, it will first be canceled.
     *
     * <p>Like {@link #set}, except you can also supply a period at which
     * the alarm will automatically repeat.  This alarm continues
     * repeating until explicitly removed with {@link #cancel}.  If the stated
     * trigger time is in the past, the alarm will be triggered immediately, with an
     * alarm count depending on how far in the past the trigger time is relative
     * to the repeat interval.
     *
     * <p>If an alarm is delayed (by system sleep, for example, for non
     * _WAKEUP alarm types), a skipped repeat will be delivered as soon as
     * possible.  After that, future alarms will be delivered according to the
     * original schedule; they do not drift over time.  For example, if you have
     * set a recurring alarm for the top of every hour but the phone was asleep
     * from 7:45 until 8:45, an alarm will be sent as soon as the phone awakens,
     * then the next alarm will be sent at 9:00.
     *
     * <p>If your application wants to allow the delivery times to drift in
     * order to guarantee that at least a certain time interval always elapses
     * between alarms, then the approach to take is to use one-time alarms,
     * scheduling the next one yourself when handling each alarm delivery.
     *
     * <p class="note">
     * <b>Note:</b> as of API 19, all repeating alarms are inexact.  If your
     * application needs precise delivery times then it must use one-time
     * exact alarms, rescheduling each time as described above. Legacy applications
     * whose {@code targetSdkVersion} is earlier than API 19 will continue to have all
     * of their alarms, including repeating alarms, treated as exact.
     * <p>Apps targeting {@link Build.VERSION_CODES#S} will need to set the flag
     * {@link PendingIntent#FLAG_MUTABLE} on the {@link PendingIntent} being used to set this alarm,
     * if they want the alarm count to be supplied with the key {@link Intent#EXTRA_ALARM_COUNT}.
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should first
     * go off, using the appropriate clock (depending on the alarm type).
     * @param intervalMillis interval in milliseconds between subsequent repeats
     * of the alarm.
     * @param operation Action to perform when the alarm goes off;
     * typically comes from {@link PendingIntent#getBroadcast
     * IntentSender.getBroadcast()}.
     *
     * @see android.os.Handler
     * @see #set
     * @see #setExact
     * @see #setWindow
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     * @see Intent#EXTRA_ALARM_COUNT
     */
    public void setRepeating(@AlarmType int type, long triggerAtMillis,
            long intervalMillis, PendingIntent operation) {
        setImpl(type, triggerAtMillis, legacyExactLength(), intervalMillis, 0, operation,
                null, null, (Handler) null, null, null);
    }

    /**
     * Schedule an alarm to be delivered within a given window of time.  This method
     * is similar to {@link #set(int, long, PendingIntent)}, but allows the
     * application to precisely control the degree to which its delivery might be
     * adjusted by the OS. This method allows an application to take advantage of the
     * battery optimizations that arise from delivery batching even when it has
     * modest timeliness requirements for its alarms.
     *
     * <p>
     * Note: Starting with API {@link Build.VERSION_CODES#S}, apps should not pass in a window of
     * less than 10 minutes. The system will try its best to accommodate smaller windows if the
     * alarm is supposed to fire in the near future, but there are no guarantees and the app should
     * expect any window smaller than 10 minutes to get elongated to 10 minutes.
     *
     * <p>
     * This method can also be used to achieve strict ordering guarantees among
     * multiple alarms by ensuring that the windows requested for each alarm do
     * not intersect.
     *
     * <p>
     * When precise delivery is not required, applications should use the standard
     * {@link #set(int, long, PendingIntent)} method.  This will give the OS the most
     * flexibility to minimize wakeups and battery use.  For alarms that must be delivered
     * at precisely-specified times with no acceptable variation, applications can use
     * {@link #setExact(int, long, PendingIntent)}.
     *
     * @param type type of alarm.
     * @param windowStartMillis The earliest time, in milliseconds, that the alarm should
     *        be delivered, expressed in the appropriate clock's units (depending on the alarm
     *        type).
     * @param windowLengthMillis The length of the requested delivery window,
     *        in milliseconds.  The alarm will be delivered no later than this many
     *        milliseconds after {@code windowStartMillis}.  Note that this parameter
     *        is a <i>duration,</i> not the timestamp of the end of the window.
     * @param operation Action to perform when the alarm goes off;
     *        typically comes from {@link PendingIntent#getBroadcast
     *        IntentSender.getBroadcast()}.
     *
     * @see #set
     * @see #setExact
     * @see #setRepeating
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     */
    public void setWindow(@AlarmType int type, long windowStartMillis, long windowLengthMillis,
            PendingIntent operation) {
        setImpl(type, windowStartMillis, windowLengthMillis, 0, 0, operation,
                null, null, (Handler) null, null, null);
    }

    /**
     * Direct callback version of {@link #setWindow(int, long, long, PendingIntent)}.  Rather
     * than supplying a PendingIntent to be sent when the alarm time is reached, this variant
     * supplies an {@link OnAlarmListener} instance that will be invoked at that time.
     * <p>
     * The OnAlarmListener {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     * invoked via the specified target Handler, or on the application's main looper
     * if {@code null} is passed as the {@code targetHandler} parameter.
     *
     * <p>
     * Note: Starting with API {@link Build.VERSION_CODES#S}, apps should not pass in a window of
     * less than 10 minutes. The system will try its best to accommodate smaller windows if the
     * alarm is supposed to fire in the near future, but there are no guarantees and the app should
     * expect any window smaller than 10 minutes to get elongated to 10 minutes.
     *
     * @see #setWindow(int, long, long, PendingIntent)
     */
    public void setWindow(@AlarmType int type, long windowStartMillis, long windowLengthMillis,
            String tag, OnAlarmListener listener, Handler targetHandler) {
        setImpl(type, windowStartMillis, windowLengthMillis, 0, 0, null, listener, tag,
                targetHandler, null, null);
    }

    /**
     * Schedule an alarm that is prioritized by the system while the device is in power saving modes
     * such as battery saver and device idle (doze).
     *
     * <p>
     * Apps that use this are not guaranteed to get all alarms as requested during power saving
     * modes, i.e. the system may still impose restrictions on how frequently these alarms will go
     * off for a particular application, like requiring a certain minimum duration be elapsed
     * between consecutive alarms. This duration will be normally be in the order of a few minutes.
     *
     * <p>
     * When the system wakes up to deliver these alarms, it may not deliver any of the other pending
     * alarms set earlier by the calling app, even the special ones set via
     * {@link #setAndAllowWhileIdle(int, long, PendingIntent)} or
     * {@link #setExactAndAllowWhileIdle(int, long, PendingIntent)}. So the caller should not
     * expect these to arrive in any relative order to its other alarms.
     *
     * @param type type of alarm
     * @param windowStartMillis The earliest time, in milliseconds, that the alarm should
     *        be delivered, expressed in the appropriate clock's units (depending on the alarm
     *        type).
     * @param windowLengthMillis The length of the requested delivery window,
     *        in milliseconds.  The alarm will be delivered no later than this many
     *        milliseconds after {@code windowStartMillis}.  Note that this parameter
     *        is a <i>duration,</i> not the timestamp of the end of the window.
     * @param tag Optional. A string describing the alarm, used for logging and battery-use
     *         attribution.
     * @param listener {@link OnAlarmListener} instance whose
     *         {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     *         called when the alarm time is reached.  A given OnAlarmListener instance can
     *         only be the target of a single pending alarm, just as a given PendingIntent
     *         can only be used with one alarm at a time.
     * @param executor {@link Executor} on which to execute the listener's onAlarm()
     *         callback.
     * @hide
     */
    @SystemApi
    @RequiresPermission(Manifest.permission.SCHEDULE_PRIORITIZED_ALARM)
    public void setPrioritized(@AlarmType int type, long windowStartMillis, long windowLengthMillis,
            @Nullable String tag, @NonNull Executor executor, @NonNull OnAlarmListener listener) {
        Objects.requireNonNull(executor);
        Objects.requireNonNull(listener);
        setImpl(type, windowStartMillis, windowLengthMillis, 0, FLAG_PRIORITIZE, null, listener,
                tag, executor, null, null);
    }

    /**
     * Schedule an alarm to be delivered precisely at the stated time.
     *
     * <p>
     * This method is like {@link #set(int, long, PendingIntent)}, but does not permit
     * the OS to adjust the delivery time.  The alarm will be delivered as nearly as
     * possible to the requested trigger time.
     *
     * <p>
     * <b>Note:</b> only alarms for which there is a strong demand for exact-time
     * delivery (such as an alarm clock ringing at the requested time) should be
     * scheduled as exact.  Applications are strongly discouraged from using exact
     * alarms unnecessarily as they reduce the OS's ability to minimize battery use.
     *
     * <p class="note"><strong>Note:</strong>
     * Starting with {@link Build.VERSION_CODES#S}, apps targeting SDK level 31 or higher
     * need to request the
     * {@link Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM} permission to use this
     * API, unless the app is exempt from battery restrictions.
     * The user and the system can revoke this permission via the special app access screen in
     * Settings.
     *
     * <p class="note"><strong>Note:</strong>
     * Exact alarms should only be used for user-facing features.
     * For more details, see <a
     * href="{@docRoot}about/versions/12/behavior-changes-12#exact-alarm-permission">
     * Exact alarm permission</a>.
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should go
     *        off, using the appropriate clock (depending on the alarm type).
     * @param operation Action to perform when the alarm goes off;
     *        typically comes from {@link PendingIntent#getBroadcast
     *        IntentSender.getBroadcast()}.
     *
     * @see #set
     * @see #setRepeating
     * @see #setWindow
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     * @see Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM
     */
    @RequiresPermission(value = Manifest.permission.SCHEDULE_EXACT_ALARM, conditional = true)
    public void setExact(@AlarmType int type, long triggerAtMillis, PendingIntent operation) {
        setImpl(type, triggerAtMillis, WINDOW_EXACT, 0, 0, operation, null, null, (Handler) null,
                null, null);
    }

    /**
     * Direct callback version of {@link #setExact(int, long, PendingIntent)}.  Rather
     * than supplying a PendingIntent to be sent when the alarm time is reached, this variant
     * supplies an {@link OnAlarmListener} instance that will be invoked at that time.
     * <p>
     * The OnAlarmListener's {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     * invoked via the specified target Handler, or on the application's main looper
     * if {@code null} is passed as the {@code targetHandler} parameter.
     *
     * <p class="note"><strong>Note:</strong>
     * Starting with {@link Build.VERSION_CODES#S}, apps targeting SDK level 31 or higher
     * need to request the
     * {@link Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM} permission to use this
     * API, unless the app is exempt from battery restrictions.
     * The user and the system can revoke this permission via the special app access screen in
     * Settings.
     *
     * <p class="note"><strong>Note:</strong>
     * Exact alarms should only be used for user-facing features.
     * For more details, see <a
     * href="{@docRoot}about/versions/12/behavior-changes-12#exact-alarm-permission">
     * Exact alarm permission</a>.
     *
     * @see Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM
     */
    @RequiresPermission(value = Manifest.permission.SCHEDULE_EXACT_ALARM, conditional = true)
    public void setExact(@AlarmType int type, long triggerAtMillis, String tag,
            OnAlarmListener listener, Handler targetHandler) {
        setImpl(type, triggerAtMillis, WINDOW_EXACT, 0, 0, null, listener, tag,
                targetHandler, null, null);
    }

    /**
     * Schedule an idle-until alarm, which will keep the alarm manager idle until
     * the given time.
     * @hide
     */
    public void setIdleUntil(@AlarmType int type, long triggerAtMillis, String tag,
            OnAlarmListener listener, Handler targetHandler) {
        setImpl(type, triggerAtMillis, WINDOW_EXACT, 0, FLAG_IDLE_UNTIL, null,
                listener, tag, targetHandler, null, null);
    }

    /**
     * Schedule an alarm that represents an alarm clock, which will be used to notify the user
     * when it goes off.  The expectation is that when this alarm triggers, the application will
     * further wake up the device to tell the user about the alarm -- turning on the screen,
     * playing a sound, vibrating, etc.  As such, the system will typically also use the
     * information supplied here to tell the user about this upcoming alarm if appropriate.
     *
     * <p>Due to the nature of this kind of alarm, similar to {@link #setExactAndAllowWhileIdle},
     * these alarms will be allowed to trigger even if the system is in a low-power idle
     * (a.k.a. doze) mode.  The system may also do some prep-work when it sees that such an
     * alarm coming up, to reduce the amount of background work that could happen if this
     * causes the device to fully wake up -- this is to avoid situations such as a large number
     * of devices having an alarm set at the same time in the morning, all waking up at that
     * time and suddenly swamping the network with pending background work.  As such, these
     * types of alarms can be extremely expensive on battery use and should only be used for
     * their intended purpose.</p>
     *
     * <p>
     * This method is like {@link #setExact(int, long, PendingIntent)}, but implies
     * {@link #RTC_WAKEUP}.
     *
     * <p class="note"><strong>Note:</strong>
     * Starting with {@link Build.VERSION_CODES#S}, apps targeting SDK level 31 or higher
     * need to request the
     * {@link Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM} permission to use this
     * API.
     * The user and the system can revoke this permission via the special app access screen in
     * Settings.
     *
     * <p class="note"><strong>Note:</strong>
     * Exact alarms should only be used for user-facing features.
     * For more details, see <a
     * href="{@docRoot}about/versions/12/behavior-changes-12#exact-alarm-permission">
     * Exact alarm permission</a>.
     *
     * <p>Alarms scheduled via this API
     * will be allowed to start a foreground service even if the app is in the background.
     *
     * @param info
     * @param operation Action to perform when the alarm goes off;
     *        typically comes from {@link PendingIntent#getBroadcast
     *        IntentSender.getBroadcast()}.
     *
     * @see #set
     * @see #setRepeating
     * @see #setWindow
     * @see #setExact
     * @see #cancel
     * @see #getNextAlarmClock()
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM
     */
    @RequiresPermission(Manifest.permission.SCHEDULE_EXACT_ALARM)
    public void setAlarmClock(AlarmClockInfo info, PendingIntent operation) {
        setImpl(RTC_WAKEUP, info.getTriggerTime(), WINDOW_EXACT, 0, 0, operation,
                null, null, (Handler) null, null, info);
    }

    /** @hide */
    @SystemApi
    @RequiresPermission(android.Manifest.permission.UPDATE_DEVICE_STATS)
    public void set(@AlarmType int type, long triggerAtMillis, long windowMillis,
            long intervalMillis, PendingIntent operation, WorkSource workSource) {
        setImpl(type, triggerAtMillis, windowMillis, intervalMillis, 0, operation, null, null,
                (Handler) null, workSource, null);
    }

    /**
     * Direct callback version of {@link #set(int, long, long, long, PendingIntent, WorkSource)}.
     * Note that repeating alarms must use the PendingIntent variant, not an OnAlarmListener.
     * <p>
     * The OnAlarmListener's {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     * invoked via the specified target Handler, or on the application's main looper
     * if {@code null} is passed as the {@code targetHandler} parameter.
     *
     * @hide
     */
    @UnsupportedAppUsage
    public void set(@AlarmType int type, long triggerAtMillis, long windowMillis,
            long intervalMillis, String tag, OnAlarmListener listener, Handler targetHandler,
            WorkSource workSource) {
        setImpl(type, triggerAtMillis, windowMillis, intervalMillis, 0, null, listener, tag,
                targetHandler, workSource, null);
    }

    /**
     * This is only used to make an identifying tag for the deprecated
     * {@link #set(int, long, long, long, OnAlarmListener, Handler, WorkSource)} API which doesn't
     * accept a tag. For all other APIs, the tag provided by the app is used, even if it is
     * {@code null}.
     */
    private static String makeTag(long triggerMillis, WorkSource ws) {
        final StringBuilder tagBuilder = new StringBuilder(GENERATED_TAG_PREFIX);

        tagBuilder.append(":");
        final int attributionUid =
                (ws == null || ws.isEmpty()) ? Process.myUid() : ws.getAttributionUid();
        tagBuilder.append(UserHandle.formatUid(attributionUid));
        tagBuilder.append(":");
        tagBuilder.append(triggerMillis);
        return tagBuilder.toString();
    }

    /**
     * Direct callback version of {@link #set(int, long, long, long, PendingIntent, WorkSource)}.
     * Note that repeating alarms must use the PendingIntent variant, not an OnAlarmListener.
     * <p>
     * The OnAlarmListener's {@link OnAlarmListener#onAlarm() onAlarm()} method will be
     * invoked via the specified target Handler, or on the application's main looper
     * if {@code null} is passed as the {@code targetHandler} parameter.
     *
     * @hide
     */
    @SystemApi
    @RequiresPermission(android.Manifest.permission.UPDATE_DEVICE_STATS)
    public void set(@AlarmType int type, long triggerAtMillis, long windowMillis,
            long intervalMillis, OnAlarmListener listener, Handler targetHandler,
            WorkSource workSource) {
        setImpl(type, triggerAtMillis, windowMillis, intervalMillis, 0, null, listener,
                makeTag(triggerAtMillis, workSource), targetHandler, workSource, null);
    }

    /**
     * Exact version of {@link #set(int, long, long, long, OnAlarmListener, Handler, WorkSource)}.
     * This equivalent to calling the aforementioned API with {@code windowMillis} and
     * {@code intervalMillis} set to 0.
     * One subtle difference is that this API requires {@code workSource} to be non-null. If you
     * don't want to attribute this alarm to another app for battery consumption, you should use
     * {@link #setExact(int, long, String, OnAlarmListener, Handler)} instead.
     *
     * <p>
     * Note that using this API requires you to hold
     * {@link Manifest.permission#SCHEDULE_EXACT_ALARM}, unless you are on the system's power
     * allowlist. This can be set, for example, by marking the app as {@code <allow-in-power-save>}
     * within the system config.
     *
     * @param type            type of alarm
     * @param triggerAtMillis The exact time in milliseconds, that the alarm should be delivered,
     *                        expressed in the appropriate clock's units (depending on the alarm
     *                        type).
     * @param listener        {@link OnAlarmListener} instance whose
     *                        {@link OnAlarmListener#onAlarm() onAlarm()} method will be called when
     *                        the alarm time is reached.
     * @param executor        The {@link Executor} on which to execute the listener's onAlarm()
     *                        callback.
     * @param tag             Optional. A string tag used to identify this alarm in logs and
     *                        battery-attribution.
     * @param workSource      A {@link WorkSource} object to attribute this alarm to the app that
     *                        requested this work.
     * @hide
     */
    @SystemApi
    @RequiresPermission(allOf = {
            Manifest.permission.UPDATE_DEVICE_STATS,
            Manifest.permission.SCHEDULE_EXACT_ALARM}, conditional = true)
    public void setExact(@AlarmType int type, long triggerAtMillis, @Nullable String tag,
            @NonNull Executor executor, @NonNull WorkSource workSource,
            @NonNull OnAlarmListener listener) {
        Objects.requireNonNull(executor);
        Objects.requireNonNull(workSource);
        Objects.requireNonNull(listener);
        setImpl(type, triggerAtMillis, WINDOW_EXACT, 0, 0, null, listener, tag, executor,
                workSource, null);
    }


    private void setImpl(@AlarmType int type, long triggerAtMillis, long windowMillis,
            long intervalMillis, int flags, PendingIntent operation, final OnAlarmListener listener,
            String listenerTag, Handler targetHandler, WorkSource workSource,
            AlarmClockInfo alarmClock) {
        final Handler handlerToUse = (targetHandler != null) ? targetHandler : mMainThreadHandler;
        setImpl(type, triggerAtMillis, windowMillis, intervalMillis, flags, operation, listener,
                listenerTag, new HandlerExecutor(handlerToUse), workSource, alarmClock);
    }

    private void setImpl(@AlarmType int type, long triggerAtMillis, long windowMillis,
            long intervalMillis, int flags, PendingIntent operation, final OnAlarmListener listener,
            String listenerTag, Executor targetExecutor, WorkSource workSource,
            AlarmClockInfo alarmClock) {
        if (triggerAtMillis < 0) {
            /* NOTYET
            if (mAlwaysExact) {
                // Fatal error for KLP+ apps to use negative trigger times
                throw new IllegalArgumentException("Invalid alarm trigger time "
                        + triggerAtMillis);
            }
            */
            triggerAtMillis = 0;
        }

        ListenerWrapper recipientWrapper = null;
        if (listener != null) {
            synchronized (AlarmManager.class) {
                if (sWrappers == null) {
                    sWrappers = new WeakHashMap<>();
                }

                final WeakReference<ListenerWrapper> weakRef = sWrappers.get(listener);
                if (weakRef != null) {
                    recipientWrapper = weakRef.get();
                }
                // no existing wrapper => build a new one
                if (recipientWrapper == null) {
                    recipientWrapper = new ListenerWrapper(listener);
                    sWrappers.put(listener, new WeakReference<>(recipientWrapper));
                }
            }
            recipientWrapper.setExecutor(targetExecutor);
        }

        try {
            mService.set(mPackageName, type, triggerAtMillis, windowMillis, intervalMillis, flags,
                    operation, recipientWrapper, listenerTag, workSource, alarmClock);
        } catch (RemoteException ex) {
            throw ex.rethrowFromSystemServer();
        }
    }

    /**
     * Available inexact recurrence interval recognized by
     * {@link #setInexactRepeating(int, long, long, PendingIntent)}
     * when running on Android prior to API 19.
     */
    public static final long INTERVAL_FIFTEEN_MINUTES = 15 * 60 * 1000;

    /**
     * Available inexact recurrence interval recognized by
     * {@link #setInexactRepeating(int, long, long, PendingIntent)}
     * when running on Android prior to API 19.
     */
    public static final long INTERVAL_HALF_HOUR = 2*INTERVAL_FIFTEEN_MINUTES;

    /**
     * Available inexact recurrence interval recognized by
     * {@link #setInexactRepeating(int, long, long, PendingIntent)}
     * when running on Android prior to API 19.
     */
    public static final long INTERVAL_HOUR = 2*INTERVAL_HALF_HOUR;

    /**
     * Available inexact recurrence interval recognized by
     * {@link #setInexactRepeating(int, long, long, PendingIntent)}
     * when running on Android prior to API 19.
     */
    public static final long INTERVAL_HALF_DAY = 12*INTERVAL_HOUR;

    /**
     * Available inexact recurrence interval recognized by
     * {@link #setInexactRepeating(int, long, long, PendingIntent)}
     * when running on Android prior to API 19.
     */
    public static final long INTERVAL_DAY = 2*INTERVAL_HALF_DAY;

    /**
     * Schedule a repeating alarm that has inexact trigger time requirements;
     * for example, an alarm that repeats every hour, but not necessarily at
     * the top of every hour.  These alarms are more power-efficient than
     * the strict recurrences traditionally supplied by {@link #setRepeating}, since the
     * system can adjust alarms' delivery times to cause them to fire simultaneously,
     * avoiding waking the device from sleep more than necessary.
     *
     * <p>Your alarm's first trigger will not be before the requested time,
     * but it might not occur for almost a full interval after that time.  In
     * addition, while the overall period of the repeating alarm will be as
     * requested, the time between any two successive firings of the alarm
     * may vary.  If your application demands very low jitter, use
     * one-shot alarms with an appropriate window instead; see {@link
     * #setWindow(int, long, long, PendingIntent)} and
     * {@link #setExact(int, long, PendingIntent)}.
     *
     * <p class="note">
     * As of API 19, all repeating alarms are inexact.  Because this method has
     * been available since API 3, your application can safely call it and be
     * assured that it will get similar behavior on both current and older versions
     * of Android.
     * <p>Apps targeting {@link Build.VERSION_CODES#S} will need to set the flag
     * {@link PendingIntent#FLAG_MUTABLE} on the {@link PendingIntent} being used to set this alarm,
     * if they want the alarm count to be supplied with the key {@link Intent#EXTRA_ALARM_COUNT}.
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should first
     * go off, using the appropriate clock (depending on the alarm type).  This
     * is inexact: the alarm will not fire before this time, but there may be a
     * delay of almost an entire alarm interval before the first invocation of
     * the alarm.
     * @param intervalMillis interval in milliseconds between subsequent repeats
     * of the alarm.  Prior to API 19, if this is one of INTERVAL_FIFTEEN_MINUTES,
     * INTERVAL_HALF_HOUR, INTERVAL_HOUR, INTERVAL_HALF_DAY, or INTERVAL_DAY
     * then the alarm will be phase-aligned with other alarms to reduce the
     * number of wakeups.  Otherwise, the alarm will be set as though the
     * application had called {@link #setRepeating}.  As of API 19, all repeating
     * alarms will be inexact and subject to batching with other alarms regardless
     * of their stated repeat interval.
     * @param operation Action to perform when the alarm goes off;
     * typically comes from {@link PendingIntent#getBroadcast
     * IntentSender.getBroadcast()}.
     *
     * @see android.os.Handler
     * @see #set
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     * @see #INTERVAL_FIFTEEN_MINUTES
     * @see #INTERVAL_HALF_HOUR
     * @see #INTERVAL_HOUR
     * @see #INTERVAL_HALF_DAY
     * @see #INTERVAL_DAY
     * @see Intent#EXTRA_ALARM_COUNT
     */
    public void setInexactRepeating(@AlarmType int type, long triggerAtMillis,
            long intervalMillis, PendingIntent operation) {
        setImpl(type, triggerAtMillis, WINDOW_HEURISTIC, intervalMillis, 0, operation, null,
                null, (Handler) null, null, null);
    }

    /**
     * Like {@link #set(int, long, PendingIntent)}, but this alarm will be allowed to execute
     * even when the system is in low-power idle (a.k.a. doze) modes.  This type of alarm must
     * <b>only</b> be used for situations where it is actually required that the alarm go off while
     * in idle -- a reasonable example would be for a calendar notification that should make a
     * sound so the user is aware of it.  When the alarm is dispatched, the app will also be
     * added to the system's temporary power exemption list for approximately 10 seconds to allow
     * that application to acquire further wake locks in which to complete its work.</p>
     *
     * <p>These alarms can significantly impact the power use
     * of the device when idle (and thus cause significant battery blame to the app scheduling
     * them), so they should be used with care.  To reduce abuse, there are restrictions on how
     * frequently these alarms will go off for a particular application.
     * Under normal system operation, it will not dispatch these
     * alarms more than about every minute (at which point every such pending alarm is
     * dispatched); when in low-power idle modes this duration may be significantly longer,
     * such as 15 minutes.</p>
     *
     * <p>Unlike other alarms, the system is free to reschedule this type of alarm to happen
     * out of order with any other alarms, even those from the same app.  This will clearly happen
     * when the device is idle (since this alarm can go off while idle, when any other alarms
     * from the app will be held until later), but may also happen even when not idle.</p>
     *
     * <p>Regardless of the app's target SDK version, this call always allows batching of the
     * alarm.</p>
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should go
     * off, using the appropriate clock (depending on the alarm type).
     * @param operation Action to perform when the alarm goes off;
     * typically comes from {@link PendingIntent#getBroadcast
     * IntentSender.getBroadcast()}.
     *
     * @see #set(int, long, PendingIntent)
     * @see #setExactAndAllowWhileIdle
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     */
    public void setAndAllowWhileIdle(@AlarmType int type, long triggerAtMillis,
            PendingIntent operation) {
        setImpl(type, triggerAtMillis, WINDOW_HEURISTIC, 0, FLAG_ALLOW_WHILE_IDLE,
                operation, null, null, (Handler) null, null, null);
    }

    /**
     * Like {@link #setExact(int, long, PendingIntent)}, but this alarm will be allowed to execute
     * even when the system is in low-power idle modes.  If you don't need exact scheduling of
     * the alarm but still need to execute while idle, consider using
     * {@link #setAndAllowWhileIdle}.  This type of alarm must <b>only</b>
     * be used for situations where it is actually required that the alarm go off while in
     * idle -- a reasonable example would be for a calendar notification that should make a
     * sound so the user is aware of it.  When the alarm is dispatched, the app will also be
     * added to the system's temporary power exemption list for approximately 10 seconds to allow
     * that application to acquire further wake locks in which to complete its work.</p>
     *
     * <p>These alarms can significantly impact the power use
     * of the device when idle (and thus cause significant battery blame to the app scheduling
     * them), so they should be used with care.  To reduce abuse, there are restrictions on how
     * frequently these alarms will go off for a particular application.
     * Under normal system operation, it will not dispatch these
     * alarms more than about every minute (at which point every such pending alarm is
     * dispatched); when in low-power idle modes this duration may be significantly longer,
     * such as 15 minutes.</p>
     *
     * <p>Unlike other alarms, the system is free to reschedule this type of alarm to happen
     * out of order with any other alarms, even those from the same app.  This will clearly happen
     * when the device is idle (since this alarm can go off while idle, when any other alarms
     * from the app will be held until later), but may also happen even when not idle.
     * Note that the OS will allow itself more flexibility for scheduling these alarms than
     * regular exact alarms, since the application has opted into this behavior.  When the
     * device is idle it may take even more liberties with scheduling in order to optimize
     * for battery life.</p>
     *
     * <p class="note"><strong>Note:</strong>
     * Starting with {@link Build.VERSION_CODES#S}, apps targeting SDK level 31 or higher
     * need to request the
     * {@link Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM} permission to use this
     * API, unless the app is exempt from battery restrictions.
     * The user and the system can revoke this permission via the special app access screen in
     * Settings.
     *
     * <p class="note"><strong>Note:</strong>
     * Exact alarms should only be used for user-facing features.
     * For more details, see <a
     * href="{@docRoot}about/versions/12/behavior-changes-12#exact-alarm-permission">
     * Exact alarm permission</a>.
     *
     * <p>Alarms scheduled via this API
     * will be allowed to start a foreground service even if the app is in the background.
     *
     * @param type type of alarm.
     * @param triggerAtMillis time in milliseconds that the alarm should go
     *        off, using the appropriate clock (depending on the alarm type).
     * @param operation Action to perform when the alarm goes off;
     *        typically comes from {@link PendingIntent#getBroadcast
     *        IntentSender.getBroadcast()}.
     *
     * @see #set
     * @see #setRepeating
     * @see #setWindow
     * @see #cancel
     * @see android.content.Context#sendBroadcast
     * @see android.content.Context#registerReceiver
     * @see android.content.Intent#filterEquals
     * @see #ELAPSED_REALTIME
     * @see #ELAPSED_REALTIME_WAKEUP
     * @see #RTC
     * @see #RTC_WAKEUP
     * @see Manifest.permission#SCHEDULE_EXACT_ALARM SCHEDULE_EXACT_ALARM
     */
    @RequiresPermission(value = Manifest.permission.SCHEDULE_EXACT_ALARM, conditional = true)
    public void setExactAndAllowWhileIdle(@AlarmType int type, long triggerAtMillis,
            PendingIntent operation) {
        setImpl(type, triggerAtMillis, WINDOW_EXACT, 0, FLAG_ALLOW_WHILE_IDLE, operation,
                null, null, (Handler) null, null, null);
    }

    /**
     * Remove any alarms with a matching {@link Intent}.
     * Any alarm, of any type, whose Intent matches this one (as defined by
     * {@link Intent#filterEquals}), will be canceled.
     *
     * @param operation IntentSender which matches a previously added
     * IntentSender. This parameter must not be {@code null}.
     *
     * @see #set
     */
    public void cancel(PendingIntent operation) {
        if (operation == null) {
            final String msg = "cancel() called with a null PendingIntent";
            if (mTargetSdkVersion >= Build.VERSION_CODES.N) {
                throw new NullPointerException(msg);
            } else {
                Log.e(TAG, msg);
                return;
            }
        }

        try {
            mService.remove(operation, null);
        } catch (RemoteException ex) {
            throw ex.rethrowFromSystemServer();
        }
    }

    /**
     * Remove any alarm scheduled to be delivered to the given {@link OnAlarmListener}.
     *
     * @param listener OnAlarmListener instance that is the target of a currently-set alarm.
     */
    public void cancel(OnAlarmListener listener) {
        if (listener == null) {
            throw new NullPointerException("cancel() called with a null OnAlarmListener");
        }

        ListenerWrapper wrapper = null;
        synchronized (AlarmManager.class) {
            if (sWrappers != null) {
                final WeakReference<ListenerWrapper> weakRef = sWrappers.get(listener);
                if (weakRef != null) {
                    wrapper = weakRef.get();
                }
            }
        }

        if (wrapper == null) {
            Log.w(TAG, "Unrecognized alarm listener " + listener);
            return;
        }

        wrapper.cancel();
    }

    /**
     * Set the system wall clock time.
     * Requires the permission android.permission.SET_TIME.
     *
     * @param millis time in milliseconds since the Epoch
     */
    @RequiresPermission(android.Manifest.permission.SET_TIME)
    public void setTime(long millis) {
        try {
            mService.setTime(millis);
        } catch (RemoteException ex) {
            throw ex.rethrowFromSystemServer();
        }
    }

    /**
     * Sets the system's persistent default time zone. This is the time zone for all apps, even
     * after a reboot. Use {@link java.util.TimeZone#setDefault} if you just want to change the
     * time zone within your app, and even then prefer to pass an explicit
     * {@link java.util.TimeZone} to APIs that require it rather than changing the time zone for
     * all threads.
     *
     * <p> On android M and above, it is an error to pass in a non-Olson timezone to this
     * function. Note that this is a bad idea on all Android releases because POSIX and
     * the {@code TimeZone} class have opposite interpretations of {@code '+'} and {@code '-'}
     * in the same non-Olson ID.
     *
     * @param timeZone one of the Olson ids from the list returned by
     *     {@link java.util.TimeZone#getAvailableIDs}
     */
    @RequiresPermission(android.Manifest.permission.SET_TIME_ZONE)
    public void setTimeZone(String timeZone) {
        if (TextUtils.isEmpty(timeZone)) {
            return;
        }

        // Reject this timezone if it isn't an Olson zone we recognize.
        if (mTargetSdkVersion >= Build.VERSION_CODES.M) {
            boolean hasTimeZone = ZoneInfoDb.getInstance().hasTimeZone(timeZone);
            if (!hasTimeZone) {
                throw new IllegalArgumentException("Timezone: " + timeZone + " is not an Olson ID");
            }
        }

        try {
            mService.setTimeZone(timeZone);
        } catch (RemoteException ex) {
            throw ex.rethrowFromSystemServer();
        }
    }

    /** @hide */
    public long getNextWakeFromIdleTime() {
        try {
            return mService.getNextWakeFromIdleTime();
        } catch (RemoteException ex) {
            throw ex.rethrowFromSystemServer();
        }
    }

    /**
     * Called to check if the caller can schedule exact alarms.
     * Your app schedules exact alarms when it calls any of the {@code setExact...} or
     * {@link #setAlarmClock(AlarmClockInfo, PendingIntent) setAlarmClock} API methods.
     * <p>
     * Apps targeting {@link Build.VERSION_CODES#S} or higher can schedule exact alarms only if they
     * have the {@link Manifest.permission#SCHEDULE_EXACT_ALARM} permission or they are on the
     * device's power-save exemption list.
     * These apps can also
     * start {@link android.provider.Settings#ACTION_REQUEST_SCHEDULE_EXACT_ALARM} to
     * request this permission from the user.
     * <p>
     * Apps targeting lower sdk versions, can always schedule exact alarms.
     *
     * @return {@code true} if the caller can schedule exact alarms, {@code false} otherwise.
     * @see android.provider.Settings#ACTION_REQUEST_SCHEDULE_EXACT_ALARM
     * @see #setExact(int, long, PendingIntent)
     * @see #setExactAndAllowWhileIdle(int, long, PendingIntent)
     * @see #setAlarmClock(AlarmClockInfo, PendingIntent)
     * @see android.os.PowerManager#isIgnoringBatteryOptimizations(String)
     */
    public boolean canScheduleExactAlarms() {
        try {
            return mService.canScheduleExactAlarms(mContext.getOpPackageName());
        } catch (RemoteException re) {
            throw re.rethrowFromSystemServer();
        }
    }

    /**
     * Called to check if the given package in the given user has the permission
     * {@link Manifest.permission#SCHEDULE_EXACT_ALARM}.
     *
     * <p><em>Note: This is only for use by system components.</em>
     *
     * @hide
     */
    @TestApi
    public boolean hasScheduleExactAlarm(@NonNull String packageName, int userId) {
        try {
            return mService.hasScheduleExactAlarm(packageName, userId);
        } catch (RemoteException re) {
            throw re.rethrowFromSystemServer();
        }
    }

    /**
     * Gets information about the next alarm clock currently scheduled.
     *
     * The alarm clocks considered are those scheduled by any application
     * using the {@link #setAlarmClock} method.
     *
     * @return An {@link AlarmClockInfo} object describing the next upcoming alarm
     *   clock event that will occur.  If there are no alarm clock events currently
     *   scheduled, this method will return {@code null}.
     *
     * @see #setAlarmClock
     * @see AlarmClockInfo
     * @see #ACTION_NEXT_ALARM_CLOCK_CHANGED
     */
    public AlarmClockInfo getNextAlarmClock() {
        return getNextAlarmClock(mContext.getUserId());
    }

    /**
     * Gets information about the next alarm clock currently scheduled.
     *
     * The alarm clocks considered are those scheduled by any application
     * using the {@link #setAlarmClock} method within the given user.
     *
     * @return An {@link AlarmClockInfo} object describing the next upcoming alarm
     *   clock event that will occur within the given user.  If there are no alarm clock
     *   events currently scheduled in that user, this method will return {@code null}.
     *
     * @see #setAlarmClock
     * @see AlarmClockInfo
     * @see #ACTION_NEXT_ALARM_CLOCK_CHANGED
     *
     * @hide
     */
    public AlarmClockInfo getNextAlarmClock(int userId) {
        try {
            return mService.getNextAlarmClock(userId);
        } catch (RemoteException ex) {
            throw ex.rethrowFromSystemServer();
        }
    }

    /**
     * An immutable description of a scheduled "alarm clock" event.
     *
     * @see AlarmManager#setAlarmClock
     * @see AlarmManager#getNextAlarmClock
     */
    public static final class AlarmClockInfo implements Parcelable {

        private final long mTriggerTime;
        private final PendingIntent mShowIntent;

        /**
         * Creates a new alarm clock description.
         *
         * @param triggerTime time at which the underlying alarm is triggered in wall time
         *                    milliseconds since the epoch
         * @param showIntent an intent that can be used to show or edit details of
         *                        the alarm clock.
         */
        public AlarmClockInfo(long triggerTime, PendingIntent showIntent) {
            mTriggerTime = triggerTime;
            mShowIntent = showIntent;
        }

        /**
         * Use the {@link #CREATOR}
         * @hide
         */
        @SuppressWarnings("UnsafeParcelApi")
        AlarmClockInfo(Parcel in) {
            mTriggerTime = in.readLong();
            mShowIntent = in.readParcelable(PendingIntent.class.getClassLoader());
        }

        /**
         * Returns the time at which the alarm is going to trigger.
         *
         * This value is UTC wall clock time in milliseconds, as returned by
         * {@link System#currentTimeMillis()} for example.
         */
        public long getTriggerTime() {
            return mTriggerTime;
        }

        /**
         * Returns an intent that can be used to show or edit details of the alarm clock in
         * the application that scheduled it.
         *
         * <p class="note">Beware that any application can retrieve and send this intent,
         * potentially with additional fields filled in. See
         * {@link PendingIntent#send(android.content.Context, int, android.content.Intent)
         * PendingIntent.send()} and {@link android.content.Intent#fillIn Intent.fillIn()}
         * for details.
         */
        public PendingIntent getShowIntent() {
            return mShowIntent;
        }

        @Override
        public int describeContents() {
            return 0;
        }

        @Override
        public void writeToParcel(Parcel dest, int flags) {
            dest.writeLong(mTriggerTime);
            dest.writeParcelable(mShowIntent, flags);
        }

        public static final @android.annotation.NonNull Creator<AlarmClockInfo> CREATOR = new Creator<AlarmClockInfo>() {
            @Override
            public AlarmClockInfo createFromParcel(Parcel in) {
                return new AlarmClockInfo(in);
            }

            @Override
            public AlarmClockInfo[] newArray(int size) {
                return new AlarmClockInfo[size];
            }
        };

        /** @hide */
        public void dumpDebug(ProtoOutputStream proto, long fieldId) {
            final long token = proto.start(fieldId);
            proto.write(AlarmClockInfoProto.TRIGGER_TIME_MS, mTriggerTime);
            if (mShowIntent != null) {
                mShowIntent.dumpDebug(proto, AlarmClockInfoProto.SHOW_INTENT);
            }
            proto.end(token);
        }
    }
}