| /* |
| * Copyright (C) 2017 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.view.textclassifier; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.annotation.SystemService; |
| import android.annotation.UnsupportedAppUsage; |
| import android.app.ActivityThread; |
| import android.content.Context; |
| import android.database.ContentObserver; |
| import android.os.ServiceManager; |
| import android.provider.DeviceConfig; |
| import android.provider.DeviceConfig.Properties; |
| import android.provider.Settings; |
| import android.service.textclassifier.TextClassifierService; |
| import android.view.textclassifier.TextClassifier.TextClassifierType; |
| |
| import com.android.internal.annotations.GuardedBy; |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.util.IndentingPrintWriter; |
| import com.android.internal.util.Preconditions; |
| |
| import java.lang.ref.WeakReference; |
| |
| /** |
| * Interface to the text classification service. |
| */ |
| @SystemService(Context.TEXT_CLASSIFICATION_SERVICE) |
| public final class TextClassificationManager { |
| |
| private static final String LOG_TAG = "TextClassificationManager"; |
| |
| private static final TextClassificationConstants sDefaultSettings = |
| new TextClassificationConstants(() -> null); |
| |
| private final Object mLock = new Object(); |
| private final TextClassificationSessionFactory mDefaultSessionFactory = |
| classificationContext -> new TextClassificationSession( |
| classificationContext, getTextClassifier()); |
| |
| private final Context mContext; |
| private final SettingsObserver mSettingsObserver; |
| |
| @GuardedBy("mLock") |
| @Nullable |
| private TextClassifier mCustomTextClassifier; |
| @GuardedBy("mLock") |
| @Nullable |
| private TextClassifier mLocalTextClassifier; |
| @GuardedBy("mLock") |
| @Nullable |
| private TextClassifier mSystemTextClassifier; |
| @GuardedBy("mLock") |
| private TextClassificationSessionFactory mSessionFactory; |
| @GuardedBy("mLock") |
| private TextClassificationConstants mSettings; |
| |
| /** @hide */ |
| public TextClassificationManager(Context context) { |
| mContext = Preconditions.checkNotNull(context); |
| mSessionFactory = mDefaultSessionFactory; |
| mSettingsObserver = new SettingsObserver(this); |
| } |
| |
| /** |
| * Returns the text classifier that was set via {@link #setTextClassifier(TextClassifier)}. |
| * If this is null, this method returns a default text classifier (i.e. either the system text |
| * classifier if one exists, or a local text classifier running in this process.) |
| * <p> |
| * Note that requests to the TextClassifier may be handled in an OEM-provided process rather |
| * than in the calling app's process. |
| * |
| * @see #setTextClassifier(TextClassifier) |
| */ |
| @NonNull |
| public TextClassifier getTextClassifier() { |
| synchronized (mLock) { |
| if (mCustomTextClassifier != null) { |
| return mCustomTextClassifier; |
| } else if (isSystemTextClassifierEnabled()) { |
| return getSystemTextClassifier(); |
| } else { |
| return getLocalTextClassifier(); |
| } |
| } |
| } |
| |
| /** |
| * Sets the text classifier. |
| * Set to null to use the system default text classifier. |
| * Set to {@link TextClassifier#NO_OP} to disable text classifier features. |
| */ |
| public void setTextClassifier(@Nullable TextClassifier textClassifier) { |
| synchronized (mLock) { |
| mCustomTextClassifier = textClassifier; |
| } |
| } |
| |
| /** |
| * Returns a specific type of text classifier. |
| * If the specified text classifier cannot be found, this returns {@link TextClassifier#NO_OP}. |
| * |
| * @see TextClassifier#LOCAL |
| * @see TextClassifier#SYSTEM |
| * @hide |
| */ |
| @UnsupportedAppUsage |
| public TextClassifier getTextClassifier(@TextClassifierType int type) { |
| switch (type) { |
| case TextClassifier.LOCAL: |
| return getLocalTextClassifier(); |
| default: |
| return getSystemTextClassifier(); |
| } |
| } |
| |
| private TextClassificationConstants getSettings() { |
| synchronized (mLock) { |
| if (mSettings == null) { |
| mSettings = new TextClassificationConstants( |
| () -> Settings.Global.getString( |
| getApplicationContext().getContentResolver(), |
| Settings.Global.TEXT_CLASSIFIER_CONSTANTS)); |
| } |
| return mSettings; |
| } |
| } |
| |
| /** |
| * Call this method to start a text classification session with the given context. |
| * A session is created with a context helping the classifier better understand |
| * what the user needs and consists of queries and feedback events. The queries |
| * are directly related to providing useful functionality to the user and the events |
| * are a feedback loop back to the classifier helping it learn and better serve |
| * future queries. |
| * |
| * <p> All interactions with the returned classifier are considered part of a single |
| * session and are logically grouped. For example, when a text widget is focused |
| * all user interactions around text editing (selection, editing, etc) can be |
| * grouped together to allow the classifier get better. |
| * |
| * @param classificationContext The context in which classification would occur |
| * |
| * @return An instance to perform classification in the given context |
| */ |
| @NonNull |
| public TextClassifier createTextClassificationSession( |
| @NonNull TextClassificationContext classificationContext) { |
| Preconditions.checkNotNull(classificationContext); |
| final TextClassifier textClassifier = |
| mSessionFactory.createTextClassificationSession(classificationContext); |
| Preconditions.checkNotNull(textClassifier, "Session Factory should never return null"); |
| return textClassifier; |
| } |
| |
| /** |
| * @see #createTextClassificationSession(TextClassificationContext, TextClassifier) |
| * @hide |
| */ |
| public TextClassifier createTextClassificationSession( |
| TextClassificationContext classificationContext, TextClassifier textClassifier) { |
| Preconditions.checkNotNull(classificationContext); |
| Preconditions.checkNotNull(textClassifier); |
| return new TextClassificationSession(classificationContext, textClassifier); |
| } |
| |
| /** |
| * Sets a TextClassificationSessionFactory to be used to create session-aware TextClassifiers. |
| * |
| * @param factory the textClassification session factory. If this is null, the default factory |
| * will be used. |
| */ |
| public void setTextClassificationSessionFactory( |
| @Nullable TextClassificationSessionFactory factory) { |
| synchronized (mLock) { |
| if (factory != null) { |
| mSessionFactory = factory; |
| } else { |
| mSessionFactory = mDefaultSessionFactory; |
| } |
| } |
| } |
| |
| @Override |
| protected void finalize() throws Throwable { |
| try { |
| // Note that fields could be null if the constructor threw. |
| if (mSettingsObserver != null) { |
| getApplicationContext().getContentResolver() |
| .unregisterContentObserver(mSettingsObserver); |
| if (ConfigParser.ENABLE_DEVICE_CONFIG) { |
| DeviceConfig.removeOnPropertiesChangedListener(mSettingsObserver); |
| } |
| } |
| } finally { |
| super.finalize(); |
| } |
| } |
| |
| private TextClassifier getSystemTextClassifier() { |
| synchronized (mLock) { |
| if (mSystemTextClassifier == null && isSystemTextClassifierEnabled()) { |
| try { |
| mSystemTextClassifier = new SystemTextClassifier(mContext, getSettings()); |
| Log.d(LOG_TAG, "Initialized SystemTextClassifier"); |
| } catch (ServiceManager.ServiceNotFoundException e) { |
| Log.e(LOG_TAG, "Could not initialize SystemTextClassifier", e); |
| } |
| } |
| } |
| if (mSystemTextClassifier != null) { |
| return mSystemTextClassifier; |
| } |
| return TextClassifier.NO_OP; |
| } |
| |
| /** |
| * Returns a local textclassifier, which is running in this process. |
| */ |
| @NonNull |
| private TextClassifier getLocalTextClassifier() { |
| synchronized (mLock) { |
| if (mLocalTextClassifier == null) { |
| if (getSettings().isLocalTextClassifierEnabled()) { |
| mLocalTextClassifier = |
| new TextClassifierImpl(mContext, getSettings(), TextClassifier.NO_OP); |
| } else { |
| Log.d(LOG_TAG, "Local TextClassifier disabled"); |
| mLocalTextClassifier = TextClassifier.NO_OP; |
| } |
| } |
| return mLocalTextClassifier; |
| } |
| } |
| |
| private boolean isSystemTextClassifierEnabled() { |
| return getSettings().isSystemTextClassifierEnabled() |
| && TextClassifierService.getServiceComponentName(mContext) != null; |
| } |
| |
| /** @hide */ |
| @VisibleForTesting |
| public void invalidateForTesting() { |
| invalidate(); |
| } |
| |
| private void invalidate() { |
| synchronized (mLock) { |
| mSettings = null; |
| mLocalTextClassifier = null; |
| mSystemTextClassifier = null; |
| } |
| } |
| |
| Context getApplicationContext() { |
| return mContext.getApplicationContext() != null |
| ? mContext.getApplicationContext() |
| : mContext; |
| } |
| |
| /** @hide **/ |
| public void dump(IndentingPrintWriter pw) { |
| getLocalTextClassifier().dump(pw); |
| getSystemTextClassifier().dump(pw); |
| getSettings().dump(pw); |
| } |
| |
| /** @hide */ |
| public static TextClassificationConstants getSettings(Context context) { |
| Preconditions.checkNotNull(context); |
| final TextClassificationManager tcm = |
| context.getSystemService(TextClassificationManager.class); |
| if (tcm != null) { |
| return tcm.getSettings(); |
| } else { |
| // Use default settings if there is no tcm. |
| return sDefaultSettings; |
| } |
| } |
| |
| private static final class SettingsObserver extends ContentObserver |
| implements DeviceConfig.OnPropertiesChangedListener { |
| |
| private final WeakReference<TextClassificationManager> mTcm; |
| |
| SettingsObserver(TextClassificationManager tcm) { |
| super(null); |
| mTcm = new WeakReference<>(tcm); |
| tcm.getApplicationContext().getContentResolver().registerContentObserver( |
| Settings.Global.getUriFor(Settings.Global.TEXT_CLASSIFIER_CONSTANTS), |
| false /* notifyForDescendants */, |
| this); |
| if (ConfigParser.ENABLE_DEVICE_CONFIG) { |
| DeviceConfig.addOnPropertiesChangedListener( |
| DeviceConfig.NAMESPACE_TEXTCLASSIFIER, |
| ActivityThread.currentApplication().getMainExecutor(), |
| this); |
| } |
| } |
| |
| @Override |
| public void onChange(boolean selfChange) { |
| invalidateSettings(); |
| } |
| |
| @Override |
| public void onPropertiesChanged(Properties properties) { |
| invalidateSettings(); |
| } |
| |
| private void invalidateSettings() { |
| final TextClassificationManager tcm = mTcm.get(); |
| if (tcm != null) { |
| tcm.invalidate(); |
| } |
| } |
| } |
| } |