Java tutorial
/** * Copyright (C) 2014 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.usage; import android.annotation.IntDef; import android.annotation.SystemApi; import android.annotation.UnsupportedAppUsage; import android.content.res.Configuration; import android.os.Build; import android.os.Parcel; import android.os.Parcelable; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.util.Arrays; import java.util.List; /** * A result returned from {@link android.app.usage.UsageStatsManager#queryEvents(long, long)} * from which to read {@link android.app.usage.UsageEvents.Event} objects. */ public final class UsageEvents implements Parcelable { /** @hide */ public static final String INSTANT_APP_PACKAGE_NAME = "android.instant_app"; /** @hide */ public static final String INSTANT_APP_CLASS_NAME = "android.instant_class"; /** * An event representing a state change for a component. */ public static final class Event { /** * No event type. */ public static final int NONE = 0; /** * An event type denoting that a component moved to the foreground. */ public static final int MOVE_TO_FOREGROUND = 1; /** * An event type denoting that a component moved to the background. */ public static final int MOVE_TO_BACKGROUND = 2; /** * An event type denoting that a component was in the foreground when the stats * rolled-over. This is effectively treated as a {@link #MOVE_TO_BACKGROUND}. * {@hide} */ public static final int END_OF_DAY = 3; /** * An event type denoting that a component was in the foreground the previous day. * This is effectively treated as a {@link #MOVE_TO_FOREGROUND}. * {@hide} */ public static final int CONTINUE_PREVIOUS_DAY = 4; /** * An event type denoting that the device configuration has changed. */ public static final int CONFIGURATION_CHANGE = 5; /** * An event type denoting that a package was interacted with in some way by the system. * @hide */ @SystemApi public static final int SYSTEM_INTERACTION = 6; /** * An event type denoting that a package was interacted with in some way by the user. */ public static final int USER_INTERACTION = 7; /** * An event type denoting that an action equivalent to a ShortcutInfo is taken by the user. * * @see android.content.pm.ShortcutManager#reportShortcutUsed(String) */ public static final int SHORTCUT_INVOCATION = 8; /** * An event type denoting that a package was selected by the user for ChooserActivity. * @hide */ public static final int CHOOSER_ACTION = 9; /** * An event type denoting that a notification was viewed by the user. * @hide */ @SystemApi public static final int NOTIFICATION_SEEN = 10; /** * An event type denoting a change in App Standby Bucket. The new bucket can be * retrieved by calling {@link #getAppStandbyBucket()}. * * @see UsageStatsManager#getAppStandbyBucket() */ public static final int STANDBY_BUCKET_CHANGED = 11; /** * An event type denoting that an app posted an interruptive notification. Visual and * audible interruptions are included. * @hide */ @SystemApi public static final int NOTIFICATION_INTERRUPTION = 12; /** * A Slice was pinned by the default launcher or the default assistant. * @hide */ @SystemApi public static final int SLICE_PINNED_PRIV = 13; /** * A Slice was pinned by an app. * @hide */ @SystemApi public static final int SLICE_PINNED = 14; /** * An event type denoting that the screen has gone in to an interactive state (turned * on for full user interaction, not ambient display or other non-interactive state). */ public static final int SCREEN_INTERACTIVE = 15; /** * An event type denoting that the screen has gone in to a non-interactive state * (completely turned off or turned on only in a non-interactive state like ambient * display). */ public static final int SCREEN_NON_INTERACTIVE = 16; /** * An event type denoting that the screen's keyguard has been shown, whether or not * the screen is off. */ public static final int KEYGUARD_SHOWN = 17; /** * An event type denoting that the screen's keyguard has been hidden. This typically * happens when the user unlocks their phone after turning it on. */ public static final int KEYGUARD_HIDDEN = 18; /** @hide */ public static final int FLAG_IS_PACKAGE_INSTANT_APP = 1 << 0; /** @hide */ @IntDef(flag = true, prefix = { "FLAG_" }, value = { FLAG_IS_PACKAGE_INSTANT_APP, }) @Retention(RetentionPolicy.SOURCE) public @interface EventFlags { } /** * {@hide} */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public String mPackage; /** * {@hide} */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public String mClass; /** * {@hide} */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public long mTimeStamp; /** * {@hide} */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public int mEventType; /** * Only present for {@link #CONFIGURATION_CHANGE} event types. * {@hide} */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public Configuration mConfiguration; /** * ID of the shortcut. * Only present for {@link #SHORTCUT_INVOCATION} event types. * {@hide} */ public String mShortcutId; /** * Action type passed to ChooserActivity * Only present for {@link #CHOOSER_ACTION} event types. * {@hide} */ public String mAction; /** * Content type passed to ChooserActivity. * Only present for {@link #CHOOSER_ACTION} event types. * {@hide} */ public String mContentType; /** * Content annotations passed to ChooserActivity. * Only present for {@link #CHOOSER_ACTION} event types. * {@hide} */ public String[] mContentAnnotations; /** * The app standby bucket assigned and reason. Bucket is the high order 16 bits, reason * is the low order 16 bits. * Only present for {@link #STANDBY_BUCKET_CHANGED} event types * {@hide} */ public int mBucketAndReason; /** * The id of the {@link android.app.NotificationChannel} to which an interruptive * notification was posted. * Only present for {@link #NOTIFICATION_INTERRUPTION} event types. * {@hide} */ public String mNotificationChannelId; /** @hide */ @EventFlags public int mFlags; public Event() { } /** @hide */ public Event(Event orig) { mPackage = orig.mPackage; mClass = orig.mClass; mTimeStamp = orig.mTimeStamp; mEventType = orig.mEventType; mConfiguration = orig.mConfiguration; mShortcutId = orig.mShortcutId; mAction = orig.mAction; mContentType = orig.mContentType; mContentAnnotations = orig.mContentAnnotations; mFlags = orig.mFlags; mBucketAndReason = orig.mBucketAndReason; mNotificationChannelId = orig.mNotificationChannelId; } /** * The package name of the source of this event. */ public String getPackageName() { return mPackage; } /** * The class name of the source of this event. This may be null for * certain events. */ public String getClassName() { return mClass; } /** * The time at which this event occurred, measured in milliseconds since the epoch. * <p/> * See {@link System#currentTimeMillis()}. */ public long getTimeStamp() { return mTimeStamp; } /** * The event type. * * @see #MOVE_TO_BACKGROUND * @see #MOVE_TO_FOREGROUND * @see #CONFIGURATION_CHANGE * @see #USER_INTERACTION * @see #STANDBY_BUCKET_CHANGED */ public int getEventType() { return mEventType; } /** * Returns a {@link Configuration} for this event if the event is of type * {@link #CONFIGURATION_CHANGE}, otherwise it returns null. */ public Configuration getConfiguration() { return mConfiguration; } /** * Returns the ID of a {@link android.content.pm.ShortcutInfo} for this event * if the event is of type {@link #SHORTCUT_INVOCATION}, otherwise it returns null. * * @see android.content.pm.ShortcutManager#reportShortcutUsed(String) */ public String getShortcutId() { return mShortcutId; } /** * Returns the standby bucket of the app, if the event is of type * {@link #STANDBY_BUCKET_CHANGED}, otherwise returns 0. * @return the standby bucket associated with the event. * @hide */ public int getStandbyBucket() { return (mBucketAndReason & 0xFFFF0000) >>> 16; } /** * Returns the standby bucket of the app, if the event is of type * {@link #STANDBY_BUCKET_CHANGED}, otherwise returns 0. * @return the standby bucket associated with the event. * */ public int getAppStandbyBucket() { return (mBucketAndReason & 0xFFFF0000) >>> 16; } /** * Returns the reason for the bucketing, if the event is of type * {@link #STANDBY_BUCKET_CHANGED}, otherwise returns 0. Reason values include * the main reason which is one of REASON_MAIN_*, OR'ed with REASON_SUB_*, if there * are sub-reasons for the main reason, such as REASON_SUB_USAGE_* when the main reason * is REASON_MAIN_USAGE. * @hide */ public int getStandbyReason() { return mBucketAndReason & 0x0000FFFF; } /** * Returns the ID of the {@link android.app.NotificationChannel} for this event if the * event is of type {@link #NOTIFICATION_INTERRUPTION}, otherwise it returns null; * @hide */ @SystemApi public String getNotificationChannelId() { return mNotificationChannelId; } /** @hide */ public Event getObfuscatedIfInstantApp() { if ((mFlags & FLAG_IS_PACKAGE_INSTANT_APP) == 0) { return this; } final Event ret = new Event(this); ret.mPackage = INSTANT_APP_PACKAGE_NAME; ret.mClass = INSTANT_APP_CLASS_NAME; // Note there are other string fields too, but they're for app shortcuts and choosers, // which instant apps can't use anyway, so there's no need to hide them. return ret; } } // Only used when creating the resulting events. Not used for reading/unparceling. @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private List<Event> mEventsToWrite = null; // Only used for reading/unparceling events. @UnsupportedAppUsage private Parcel mParcel = null; @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private final int mEventCount; @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private int mIndex = 0; /* * In order to save space, since ComponentNames will be duplicated everywhere, * we use a map and index into it. */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private String[] mStringPool; /** * Construct the iterator from a parcel. * {@hide} */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public UsageEvents(Parcel in) { byte[] bytes = in.readBlob(); Parcel data = Parcel.obtain(); data.unmarshall(bytes, 0, bytes.length); data.setDataPosition(0); mEventCount = data.readInt(); mIndex = data.readInt(); if (mEventCount > 0) { mStringPool = data.createStringArray(); final int listByteLength = data.readInt(); final int positionInParcel = data.readInt(); mParcel = Parcel.obtain(); mParcel.setDataPosition(0); mParcel.appendFrom(data, data.dataPosition(), listByteLength); mParcel.setDataSize(mParcel.dataPosition()); mParcel.setDataPosition(positionInParcel); } } /** * Create an empty iterator. * {@hide} */ UsageEvents() { mEventCount = 0; } /** * Construct the iterator in preparation for writing it to a parcel. * {@hide} */ public UsageEvents(List<Event> events, String[] stringPool) { mStringPool = stringPool; mEventCount = events.size(); mEventsToWrite = events; } /** * Returns whether or not there are more events to read using * {@link #getNextEvent(android.app.usage.UsageEvents.Event)}. * * @return true if there are more events, false otherwise. */ public boolean hasNextEvent() { return mIndex < mEventCount; } /** * Retrieve the next {@link android.app.usage.UsageEvents.Event} from the collection and put the * resulting data into {@code eventOut}. * * @param eventOut The {@link android.app.usage.UsageEvents.Event} object that will receive the * next event data. * @return true if an event was available, false if there are no more events. */ public boolean getNextEvent(Event eventOut) { if (mIndex >= mEventCount) { return false; } readEventFromParcel(mParcel, eventOut); mIndex++; if (mIndex >= mEventCount) { mParcel.recycle(); mParcel = null; } return true; } /** * Resets the collection so that it can be iterated over from the beginning. * * @hide When this object is iterated to completion, the parcel is destroyed and * so resetToStart doesn't work. */ public void resetToStart() { mIndex = 0; if (mParcel != null) { mParcel.setDataPosition(0); } } @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private int findStringIndex(String str) { final int index = Arrays.binarySearch(mStringPool, str); if (index < 0) { throw new IllegalStateException("String '" + str + "' is not in the string pool"); } return index; } /** * Writes a single event to the parcel. Modify this when updating {@link Event}. */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private void writeEventToParcel(Event event, Parcel p, int flags) { final int packageIndex; if (event.mPackage != null) { packageIndex = findStringIndex(event.mPackage); } else { packageIndex = -1; } final int classIndex; if (event.mClass != null) { classIndex = findStringIndex(event.mClass); } else { classIndex = -1; } p.writeInt(packageIndex); p.writeInt(classIndex); p.writeInt(event.mEventType); p.writeLong(event.mTimeStamp); switch (event.mEventType) { case Event.CONFIGURATION_CHANGE: event.mConfiguration.writeToParcel(p, flags); break; case Event.SHORTCUT_INVOCATION: p.writeString(event.mShortcutId); break; case Event.CHOOSER_ACTION: p.writeString(event.mAction); p.writeString(event.mContentType); p.writeStringArray(event.mContentAnnotations); break; case Event.STANDBY_BUCKET_CHANGED: p.writeInt(event.mBucketAndReason); break; case Event.NOTIFICATION_INTERRUPTION: p.writeString(event.mNotificationChannelId); break; } } /** * Reads a single event from the parcel. Modify this when updating {@link Event}. */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) private void readEventFromParcel(Parcel p, Event eventOut) { final int packageIndex = p.readInt(); if (packageIndex >= 0) { eventOut.mPackage = mStringPool[packageIndex]; } else { eventOut.mPackage = null; } final int classIndex = p.readInt(); if (classIndex >= 0) { eventOut.mClass = mStringPool[classIndex]; } else { eventOut.mClass = null; } eventOut.mEventType = p.readInt(); eventOut.mTimeStamp = p.readLong(); // Fill out the event-dependant fields. eventOut.mConfiguration = null; eventOut.mShortcutId = null; eventOut.mAction = null; eventOut.mContentType = null; eventOut.mContentAnnotations = null; eventOut.mNotificationChannelId = null; switch (eventOut.mEventType) { case Event.CONFIGURATION_CHANGE: // Extract the configuration for configuration change events. eventOut.mConfiguration = Configuration.CREATOR.createFromParcel(p); break; case Event.SHORTCUT_INVOCATION: eventOut.mShortcutId = p.readString(); break; case Event.CHOOSER_ACTION: eventOut.mAction = p.readString(); eventOut.mContentType = p.readString(); eventOut.mContentAnnotations = p.createStringArray(); break; case Event.STANDBY_BUCKET_CHANGED: eventOut.mBucketAndReason = p.readInt(); break; case Event.NOTIFICATION_INTERRUPTION: eventOut.mNotificationChannelId = p.readString(); break; } } @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel dest, int flags) { Parcel data = Parcel.obtain(); data.writeInt(mEventCount); data.writeInt(mIndex); if (mEventCount > 0) { data.writeStringArray(mStringPool); if (mEventsToWrite != null) { // Write out the events Parcel p = Parcel.obtain(); try { p.setDataPosition(0); for (int i = 0; i < mEventCount; i++) { final Event event = mEventsToWrite.get(i); writeEventToParcel(event, p, flags); } final int listByteLength = p.dataPosition(); // Write the total length of the data. data.writeInt(listByteLength); // Write our current position into the data. data.writeInt(0); // Write the data. data.appendFrom(p, 0, listByteLength); } finally { p.recycle(); } } else if (mParcel != null) { // Write the total length of the data. data.writeInt(mParcel.dataSize()); // Write out current position into the data. data.writeInt(mParcel.dataPosition()); // Write the data. data.appendFrom(mParcel, 0, mParcel.dataSize()); } else { throw new IllegalStateException("Either mParcel or mEventsToWrite must not be null"); } } // Data can be too large for a transact. Write the data as a Blob, which will be written to // ashmem if too large. dest.writeBlob(data.marshall()); } public static final Creator<UsageEvents> CREATOR = new Creator<UsageEvents>() { @Override public UsageEvents createFromParcel(Parcel source) { return new UsageEvents(source); } @Override public UsageEvents[] newArray(int size) { return new UsageEvents[size]; } }; }