431 lines
18 KiB
Java
431 lines
18 KiB
Java
|
/*
|
||
|
|
* Copyright (C) 2015 The Android Open Source Project
|
||
|
|
*
|
||
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
* you may not use this file except in compliance with the License.
|
||
|
|
* You may obtain a copy of the License at
|
||
|
|
*
|
||
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
*
|
||
|
|
* Unless required by applicable law or agreed to in writing, software
|
||
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
* See the License for the specific language governing permissions and
|
||
|
|
* limitations under the License.
|
||
|
|
*/
|
||
|
|
|
||
|
|
package com.android.inputmethod.latin.spellcheck;
|
||
|
|
|
||
|
|
import android.content.ContentResolver;
|
||
|
|
import android.content.Context;
|
||
|
|
import android.database.ContentObserver;
|
||
|
|
import android.database.Cursor;
|
||
|
|
import android.net.Uri;
|
||
|
|
import android.provider.UserDictionary;
|
||
|
|
import android.util.Log;
|
||
|
|
|
||
|
|
import com.android.inputmethod.annotations.UsedForTesting;
|
||
|
|
import com.android.inputmethod.latin.common.LocaleUtils;
|
||
|
|
|
||
|
|
import java.io.Closeable;
|
||
|
|
import java.util.ArrayList;
|
||
|
|
import java.util.HashMap;
|
||
|
|
import java.util.Locale;
|
||
|
|
import java.util.concurrent.atomic.AtomicBoolean;
|
||
|
|
import java.util.concurrent.Executors;
|
||
|
|
import java.util.concurrent.ScheduledExecutorService;
|
||
|
|
import java.util.concurrent.ScheduledFuture;
|
||
|
|
import java.util.concurrent.TimeUnit;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* UserDictionaryLookup provides the ability to lookup into the system-wide "Personal dictionary".
|
||
|
|
*
|
||
|
|
* Note, that the initial dictionary loading happens asynchronously so it is possible (hopefully
|
||
|
|
* rarely) that isValidWord is called before the initial load has started.
|
||
|
|
*
|
||
|
|
* The caller should explicitly call close() when the object is no longer needed, in order to
|
||
|
|
* release any resources and references to this object. A service should create this object in
|
||
|
|
* onCreate and close() it in onDestroy.
|
||
|
|
*/
|
||
|
|
public class UserDictionaryLookup implements Closeable {
|
||
|
|
private static final String TAG = UserDictionaryLookup.class.getSimpleName();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* This guards the execution of any Log.d() logging, so that if false, they are not even
|
||
|
|
*/
|
||
|
|
private static final boolean DEBUG = false;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* To avoid loading too many dictionary entries in memory, we cap them at this number. If
|
||
|
|
* that number is exceeded, the lowest-frequency items will be dropped. Note, there is no
|
||
|
|
* explicit cap on the number of locales in every entry.
|
||
|
|
*/
|
||
|
|
private static final int MAX_NUM_ENTRIES = 1000;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The delay (in milliseconds) to impose on reloads. Previously scheduled reloads will be
|
||
|
|
* cancelled if a new reload is scheduled before the delay expires. Thus, only the last
|
||
|
|
* reload in the series of frequent reloads will execute.
|
||
|
|
*
|
||
|
|
* Note, this value should be low enough to allow the "Add to dictionary" feature in the
|
||
|
|
* TextView correction (red underline) drop-down menu to work properly in the following case:
|
||
|
|
*
|
||
|
|
* 1. User types OOV (out-of-vocabulary) word.
|
||
|
|
* 2. The OOV is red-underlined.
|
||
|
|
* 3. User selects "Add to dictionary". The red underline disappears while the OOV is
|
||
|
|
* in a composing span.
|
||
|
|
* 4. The user taps space. The red underline should NOT reappear. If this value is very
|
||
|
|
* high and the user performs the space tap fast enough, the red underline may reappear.
|
||
|
|
*/
|
||
|
|
@UsedForTesting
|
||
|
|
static final int RELOAD_DELAY_MS = 200;
|
||
|
|
|
||
|
|
private final ContentResolver mResolver;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Executor on which to perform the initial load and subsequent reloads (after a delay).
|
||
|
|
*/
|
||
|
|
private final ScheduledExecutorService mLoadExecutor =
|
||
|
|
Executors.newSingleThreadScheduledExecutor();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Runnable that calls loadUserDictionary().
|
||
|
|
*/
|
||
|
|
private class UserDictionaryLoader implements Runnable {
|
||
|
|
@Override
|
||
|
|
public void run() {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Executing (re)load");
|
||
|
|
}
|
||
|
|
loadUserDictionary();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
private final UserDictionaryLoader mLoader = new UserDictionaryLoader();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Content observer for UserDictionary changes. It has the following properties:
|
||
|
|
* 1. It spawns off a UserDictionary reload in another thread, after some delay.
|
||
|
|
* 2. It cancels previously scheduled reloads, and only executes the latest.
|
||
|
|
* 3. It may be called multiple times quickly in succession (and is in fact called so
|
||
|
|
* when UserDictionary is edited through its settings UI, when sometimes multiple
|
||
|
|
* notifications are sent for the edited entry, but also for the entire UserDictionary).
|
||
|
|
*/
|
||
|
|
private class UserDictionaryContentObserver extends ContentObserver {
|
||
|
|
public UserDictionaryContentObserver() {
|
||
|
|
super(null);
|
||
|
|
}
|
||
|
|
|
||
|
|
@Override
|
||
|
|
public boolean deliverSelfNotifications() {
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Support pre-API16 platforms.
|
||
|
|
@Override
|
||
|
|
public void onChange(boolean selfChange) {
|
||
|
|
onChange(selfChange, null);
|
||
|
|
}
|
||
|
|
|
||
|
|
@Override
|
||
|
|
public void onChange(boolean selfChange, Uri uri) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Received content observer onChange notification for URI: " + uri);
|
||
|
|
}
|
||
|
|
// Cancel (but don't interrupt) any pending reloads (except the initial load).
|
||
|
|
if (mReloadFuture != null && !mReloadFuture.isCancelled() &&
|
||
|
|
!mReloadFuture.isDone()) {
|
||
|
|
// Note, that if already cancelled or done, this will do nothing.
|
||
|
|
boolean isCancelled = mReloadFuture.cancel(false);
|
||
|
|
if (DEBUG) {
|
||
|
|
if (isCancelled) {
|
||
|
|
Log.d(TAG, "Successfully canceled previous reload request");
|
||
|
|
} else {
|
||
|
|
Log.d(TAG, "Unable to cancel previous reload request");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Scheduling reload in " + RELOAD_DELAY_MS + " ms");
|
||
|
|
}
|
||
|
|
|
||
|
|
// Schedule a new reload after RELOAD_DELAY_MS.
|
||
|
|
mReloadFuture = mLoadExecutor.schedule(mLoader, RELOAD_DELAY_MS, TimeUnit.MILLISECONDS);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
private final ContentObserver mObserver = new UserDictionaryContentObserver();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Indicates that a load is in progress, so no need for another.
|
||
|
|
*/
|
||
|
|
private AtomicBoolean mIsLoading = new AtomicBoolean(false);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Indicates that this lookup object has been close()d.
|
||
|
|
*/
|
||
|
|
private AtomicBoolean mIsClosed = new AtomicBoolean(false);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* We store a map from a dictionary word to the set of locales it belongs
|
||
|
|
* in. We then iterate over the set of locales to find a match using
|
||
|
|
* LocaleUtils.
|
||
|
|
*/
|
||
|
|
private volatile HashMap<String, ArrayList<Locale>> mDictWords;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The last-scheduled reload future. Saved in order to cancel a pending reload if a new one
|
||
|
|
* is coming.
|
||
|
|
*/
|
||
|
|
private volatile ScheduledFuture<?> mReloadFuture;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @param context the context from which to obtain content resolver
|
||
|
|
*/
|
||
|
|
public UserDictionaryLookup(Context context) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "UserDictionaryLookup constructor with context: " + context);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Obtain a content resolver.
|
||
|
|
mResolver = context.getContentResolver();
|
||
|
|
|
||
|
|
// Schedule the initial load to run immediately. It's possible that the first call to
|
||
|
|
// isValidWord occurs before the dictionary has actually loaded, so it should not
|
||
|
|
// assume that the dictionary has been loaded.
|
||
|
|
mLoadExecutor.schedule(mLoader, 0, TimeUnit.MILLISECONDS);
|
||
|
|
|
||
|
|
// Register the observer to be notified on changes to the UserDictionary and all individual
|
||
|
|
// items.
|
||
|
|
//
|
||
|
|
// If the user is interacting with the UserDictionary settings UI, or with the
|
||
|
|
// "Add to dictionary" drop-down option, duplicate notifications will be sent for the same
|
||
|
|
// edit: if a new entry is added, there is a notification for the entry itself, and
|
||
|
|
// separately for the entire dictionary. However, when used programmatically,
|
||
|
|
// only notifications for the specific edits are sent. Thus, the observer is registered to
|
||
|
|
// receive every possible notification, and instead has throttling logic to avoid doing too
|
||
|
|
// many reloads.
|
||
|
|
mResolver.registerContentObserver(
|
||
|
|
UserDictionary.Words.CONTENT_URI, true /* notifyForDescendents */, mObserver);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* To be called by the garbage collector in the off chance that the service did not clean up
|
||
|
|
* properly. Do not rely on this getting called, and make sure close() is called explicitly.
|
||
|
|
*/
|
||
|
|
@Override
|
||
|
|
public void finalize() throws Throwable {
|
||
|
|
try {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Finalize called, calling close()");
|
||
|
|
}
|
||
|
|
close();
|
||
|
|
} finally {
|
||
|
|
super.finalize();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Cleans up UserDictionaryLookup: shuts down any extra threads and unregisters the observer.
|
||
|
|
*
|
||
|
|
* It is safe, but not advised to call this multiple times, and isValidWord would continue to
|
||
|
|
* work, but no data will be reloaded any longer.
|
||
|
|
*/
|
||
|
|
@Override
|
||
|
|
public void close() {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Close called (no pun intended), cleaning up executor and observer");
|
||
|
|
}
|
||
|
|
if (mIsClosed.compareAndSet(false, true)) {
|
||
|
|
// Shut down the load executor.
|
||
|
|
mLoadExecutor.shutdown();
|
||
|
|
|
||
|
|
// Unregister the content observer.
|
||
|
|
mResolver.unregisterContentObserver(mObserver);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Returns true if the initial load has been performed.
|
||
|
|
*
|
||
|
|
* @return true if the initial load is successful
|
||
|
|
*/
|
||
|
|
@UsedForTesting
|
||
|
|
boolean isLoaded() {
|
||
|
|
return mDictWords != null;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Determines if the given word is a valid word in the given locale based on the UserDictionary.
|
||
|
|
* It tries hard to find a match: for example, casing is ignored and if the word is present in a
|
||
|
|
* more general locale (e.g. en or all locales), and isValidWord is asking for a more specific
|
||
|
|
* locale (e.g. en_US), it will be considered a match.
|
||
|
|
*
|
||
|
|
* @param word the word to match
|
||
|
|
* @param locale the locale in which to match the word
|
||
|
|
* @return true iff the word has been matched for this locale in the UserDictionary.
|
||
|
|
*/
|
||
|
|
public boolean isValidWord(
|
||
|
|
final String word, final Locale locale) {
|
||
|
|
if (!isLoaded()) {
|
||
|
|
// This is a corner case in the event the initial load of UserDictionary has not
|
||
|
|
// been loaded. In that case, we assume the word is not a valid word in
|
||
|
|
// UserDictionary.
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "isValidWord invoked, but initial load not complete");
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Atomically obtain the current copy of mDictWords;
|
||
|
|
final HashMap<String, ArrayList<Locale>> dictWords = mDictWords;
|
||
|
|
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "isValidWord invoked for word [" + word +
|
||
|
|
"] in locale " + locale);
|
||
|
|
}
|
||
|
|
// Lowercase the word using the given locale. Note, that dictionary
|
||
|
|
// words are lowercased using their locale, and theoretically the
|
||
|
|
// lowercasing between two matching locales may differ. For simplicity
|
||
|
|
// we ignore that possibility.
|
||
|
|
final String lowercased = word.toLowerCase(locale);
|
||
|
|
final ArrayList<Locale> dictLocales = dictWords.get(lowercased);
|
||
|
|
if (null == dictLocales) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "isValidWord=false, since there is no entry for " +
|
||
|
|
"lowercased word [" + lowercased + "]");
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
} else {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "isValidWord found an entry for lowercased word [" + lowercased +
|
||
|
|
"]; examining locales");
|
||
|
|
}
|
||
|
|
// Iterate over the locales this word is in.
|
||
|
|
for (final Locale dictLocale : dictLocales) {
|
||
|
|
final int matchLevel = LocaleUtils.getMatchLevel(dictLocale.toString(),
|
||
|
|
locale.toString());
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "matchLevel for dictLocale=" + dictLocale + ", locale=" +
|
||
|
|
locale + " is " + matchLevel);
|
||
|
|
}
|
||
|
|
if (LocaleUtils.isMatch(matchLevel)) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "isValidWord=true, since matchLevel " + matchLevel +
|
||
|
|
" is a match");
|
||
|
|
}
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "matchLevel " + matchLevel + " is not a match");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "isValidWord=false, since none of the locales matched");
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Loads the UserDictionary in the current thread.
|
||
|
|
*
|
||
|
|
* Only one reload can happen at a time. If already running, will exit quickly.
|
||
|
|
*/
|
||
|
|
private void loadUserDictionary() {
|
||
|
|
// Bail out if already in the process of loading.
|
||
|
|
if (!mIsLoading.compareAndSet(false, true)) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Already in the process of loading UserDictionary, skipping");
|
||
|
|
}
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Loading UserDictionary");
|
||
|
|
}
|
||
|
|
HashMap<String, ArrayList<Locale>> dictWords =
|
||
|
|
new HashMap<String, ArrayList<Locale>>();
|
||
|
|
// Load the UserDictionary. Request that items be returned in the default sort order
|
||
|
|
// for UserDictionary, which is by frequency.
|
||
|
|
Cursor cursor = mResolver.query(UserDictionary.Words.CONTENT_URI,
|
||
|
|
null, null, null, UserDictionary.Words.DEFAULT_SORT_ORDER);
|
||
|
|
if (null == cursor || cursor.getCount() < 1) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "No entries found in UserDictionary");
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
// Iterate over the entries in the UserDictionary. Note, that iteration is in
|
||
|
|
// descending frequency by default.
|
||
|
|
while (dictWords.size() < MAX_NUM_ENTRIES && cursor.moveToNext()) {
|
||
|
|
// If there is no column for locale, skip this entry. An empty
|
||
|
|
// locale on the other hand will not be skipped.
|
||
|
|
final int dictLocaleIndex = cursor.getColumnIndex(
|
||
|
|
UserDictionary.Words.LOCALE);
|
||
|
|
if (dictLocaleIndex < 0) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Encountered UserDictionary entry " +
|
||
|
|
"without LOCALE, skipping");
|
||
|
|
}
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
// If there is no column for word, skip this entry.
|
||
|
|
final int dictWordIndex = cursor.getColumnIndex(
|
||
|
|
UserDictionary.Words.WORD);
|
||
|
|
if (dictWordIndex < 0) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Encountered UserDictionary entry without " +
|
||
|
|
"WORD, skipping");
|
||
|
|
}
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
// If the word is null, skip this entry.
|
||
|
|
final String rawDictWord = cursor.getString(dictWordIndex);
|
||
|
|
if (null == rawDictWord) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Encountered null word");
|
||
|
|
}
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
// If the locale is null, that's interpreted to mean all locales. Note, the special
|
||
|
|
// zz locale for an Alphabet (QWERTY) layout will not match any actual language.
|
||
|
|
String localeString = cursor.getString(dictLocaleIndex);
|
||
|
|
if (null == localeString) {
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Encountered null locale for word [" +
|
||
|
|
rawDictWord + "], assuming all locales");
|
||
|
|
}
|
||
|
|
// For purposes of LocaleUtils, an empty locale matches
|
||
|
|
// everything.
|
||
|
|
localeString = "";
|
||
|
|
}
|
||
|
|
final Locale dictLocale = LocaleUtils.constructLocaleFromString(
|
||
|
|
localeString);
|
||
|
|
// Lowercase the word before storing it.
|
||
|
|
final String dictWord = rawDictWord.toLowerCase(dictLocale);
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Incorporating UserDictionary word [" + dictWord +
|
||
|
|
"] for locale " + dictLocale);
|
||
|
|
}
|
||
|
|
// Check if there is an existing entry for this word.
|
||
|
|
ArrayList<Locale> dictLocales = dictWords.get(dictWord);
|
||
|
|
if (null == dictLocales) {
|
||
|
|
// If there is no entry for this word, create one.
|
||
|
|
if (DEBUG) {
|
||
|
|
Log.d(TAG, "Word [" + dictWord +
|
||
|
|
"] not seen for other locales, creating new entry");
|
||
|
|
}
|
||
|
|
dictLocales = new ArrayList<Locale>();
|
||
|
|
dictWords.put(dictWord, dictLocales);
|
||
|
|
}
|
||
|
|
// Append the locale to the list of locales this word is in.
|
||
|
|
dictLocales.add(dictLocale);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Atomically replace the copy of mDictWords.
|
||
|
|
mDictWords = dictWords;
|
||
|
|
|
||
|
|
// Allow other calls to loadUserDictionary to execute now.
|
||
|
|
mIsLoading.set(false);
|
||
|
|
}
|
||
|
|
}
|