| /* |
| * Copyright (C) 2011 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.service.textservice; |
| |
| import com.android.internal.textservice.ISpellCheckerService; |
| import com.android.internal.textservice.ISpellCheckerServiceCallback; |
| import com.android.internal.textservice.ISpellCheckerSession; |
| import com.android.internal.textservice.ISpellCheckerSessionListener; |
| |
| import android.app.Service; |
| import android.content.Intent; |
| import android.os.Bundle; |
| import android.os.IBinder; |
| import android.os.Process; |
| import android.os.RemoteException; |
| import android.text.TextUtils; |
| import android.text.method.WordIterator; |
| import android.util.Log; |
| import android.view.textservice.SentenceSuggestionsInfo; |
| import android.view.textservice.SuggestionsInfo; |
| import android.view.textservice.TextInfo; |
| |
| import java.lang.ref.WeakReference; |
| import java.text.BreakIterator; |
| import java.util.ArrayList; |
| import java.util.Locale; |
| |
| /** |
| * SpellCheckerService provides an abstract base class for a spell checker. |
| * This class combines a service to the system with the spell checker service interface that |
| * spell checker must implement. |
| * |
| * <p>In addition to the normal Service lifecycle methods, this class |
| * introduces a new specific callback that subclasses should override |
| * {@link #createSession()} to provide a spell checker session that is corresponding |
| * to requested language and so on. The spell checker session returned by this method |
| * should extend {@link SpellCheckerService.Session}. |
| * </p> |
| * |
| * <h3>Returning spell check results</h3> |
| * |
| * <p>{@link SpellCheckerService.Session#onGetSuggestions(TextInfo, int)} |
| * should return spell check results. |
| * It receives {@link android.view.textservice.TextInfo} and returns |
| * {@link android.view.textservice.SuggestionsInfo} for the input. |
| * You may want to override |
| * {@link SpellCheckerService.Session#onGetSuggestionsMultiple(TextInfo[], int, boolean)} for |
| * better performance and quality. |
| * </p> |
| * |
| * <p>Please note that {@link SpellCheckerService.Session#getLocale()} does not return a valid |
| * locale before {@link SpellCheckerService.Session#onCreate()} </p> |
| * |
| */ |
| public abstract class SpellCheckerService extends Service { |
| private static final String TAG = SpellCheckerService.class.getSimpleName(); |
| private static final boolean DBG = false; |
| public static final String SERVICE_INTERFACE = |
| "android.service.textservice.SpellCheckerService"; |
| |
| private final SpellCheckerServiceBinder mBinder = new SpellCheckerServiceBinder(this); |
| |
| |
| /** |
| * Implement to return the implementation of the internal spell checker |
| * service interface. Subclasses should not override. |
| */ |
| @Override |
| public final IBinder onBind(final Intent intent) { |
| if (DBG) { |
| Log.w(TAG, "onBind"); |
| } |
| return mBinder; |
| } |
| |
| /** |
| * Factory method to create a spell checker session impl |
| * @return SpellCheckerSessionImpl which should be overridden by a concrete implementation. |
| */ |
| public abstract Session createSession(); |
| |
| /** |
| * This abstract class should be overridden by a concrete implementation of a spell checker. |
| */ |
| public static abstract class Session { |
| private InternalISpellCheckerSession mInternalSession; |
| private volatile SentenceLevelAdapter mSentenceLevelAdapter; |
| |
| /** |
| * @hide |
| */ |
| public final void setInternalISpellCheckerSession(InternalISpellCheckerSession session) { |
| mInternalSession = session; |
| } |
| |
| /** |
| * This is called after the class is initialized, at which point it knows it can call |
| * getLocale() etc... |
| */ |
| public abstract void onCreate(); |
| |
| /** |
| * Get suggestions for specified text in TextInfo. |
| * This function will run on the incoming IPC thread. |
| * So, this is not called on the main thread, |
| * but will be called in series on another thread. |
| * @param textInfo the text metadata |
| * @param suggestionsLimit the maximum number of suggestions to be returned |
| * @return SuggestionsInfo which contains suggestions for textInfo |
| */ |
| public abstract SuggestionsInfo onGetSuggestions(TextInfo textInfo, int suggestionsLimit); |
| |
| /** |
| * A batch process of onGetSuggestions. |
| * This function will run on the incoming IPC thread. |
| * So, this is not called on the main thread, |
| * but will be called in series on another thread. |
| * @param textInfos an array of the text metadata |
| * @param suggestionsLimit the maximum number of suggestions to be returned |
| * @param sequentialWords true if textInfos can be treated as sequential words. |
| * @return an array of {@link SentenceSuggestionsInfo} returned by |
| * {@link SpellCheckerService.Session#onGetSuggestions(TextInfo, int)} |
| */ |
| public SuggestionsInfo[] onGetSuggestionsMultiple(TextInfo[] textInfos, |
| int suggestionsLimit, boolean sequentialWords) { |
| final int length = textInfos.length; |
| final SuggestionsInfo[] retval = new SuggestionsInfo[length]; |
| for (int i = 0; i < length; ++i) { |
| retval[i] = onGetSuggestions(textInfos[i], suggestionsLimit); |
| retval[i].setCookieAndSequence( |
| textInfos[i].getCookie(), textInfos[i].getSequence()); |
| } |
| return retval; |
| } |
| |
| /** |
| * Get sentence suggestions for specified texts in an array of TextInfo. |
| * The default implementation splits the input text to words and returns |
| * {@link SentenceSuggestionsInfo} which contains suggestions for each word. |
| * This function will run on the incoming IPC thread. |
| * So, this is not called on the main thread, |
| * but will be called in series on another thread. |
| * When you override this method, make sure that suggestionsLimit is applied to suggestions |
| * that share the same start position and length. |
| * @param textInfos an array of the text metadata |
| * @param suggestionsLimit the maximum number of suggestions to be returned |
| * @return an array of {@link SentenceSuggestionsInfo} returned by |
| * {@link SpellCheckerService.Session#onGetSuggestions(TextInfo, int)} |
| */ |
| public SentenceSuggestionsInfo[] onGetSentenceSuggestionsMultiple(TextInfo[] textInfos, |
| int suggestionsLimit) { |
| if (textInfos == null || textInfos.length == 0) { |
| return SentenceLevelAdapter.EMPTY_SENTENCE_SUGGESTIONS_INFOS; |
| } |
| if (DBG) { |
| Log.d(TAG, "onGetSentenceSuggestionsMultiple: + " + textInfos.length + ", " |
| + suggestionsLimit); |
| } |
| if (mSentenceLevelAdapter == null) { |
| synchronized(this) { |
| if (mSentenceLevelAdapter == null) { |
| final String localeStr = getLocale(); |
| if (!TextUtils.isEmpty(localeStr)) { |
| mSentenceLevelAdapter = new SentenceLevelAdapter(new Locale(localeStr)); |
| } |
| } |
| } |
| } |
| if (mSentenceLevelAdapter == null) { |
| return SentenceLevelAdapter.EMPTY_SENTENCE_SUGGESTIONS_INFOS; |
| } |
| final int infosSize = textInfos.length; |
| final SentenceSuggestionsInfo[] retval = new SentenceSuggestionsInfo[infosSize]; |
| for (int i = 0; i < infosSize; ++i) { |
| final SentenceLevelAdapter.SentenceTextInfoParams textInfoParams = |
| mSentenceLevelAdapter.getSplitWords(textInfos[i]); |
| final ArrayList<SentenceLevelAdapter.SentenceWordItem> mItems = |
| textInfoParams.mItems; |
| final int itemsSize = mItems.size(); |
| final TextInfo[] splitTextInfos = new TextInfo[itemsSize]; |
| for (int j = 0; j < itemsSize; ++j) { |
| splitTextInfos[j] = mItems.get(j).mTextInfo; |
| } |
| retval[i] = SentenceLevelAdapter.reconstructSuggestions( |
| textInfoParams, onGetSuggestionsMultiple( |
| splitTextInfos, suggestionsLimit, true)); |
| } |
| return retval; |
| } |
| |
| /** |
| * Request to abort all tasks executed in SpellChecker. |
| * This function will run on the incoming IPC thread. |
| * So, this is not called on the main thread, |
| * but will be called in series on another thread. |
| */ |
| public void onCancel() {} |
| |
| /** |
| * Request to close this session. |
| * This function will run on the incoming IPC thread. |
| * So, this is not called on the main thread, |
| * but will be called in series on another thread. |
| */ |
| public void onClose() {} |
| |
| /** |
| * @return Locale for this session |
| */ |
| public String getLocale() { |
| return mInternalSession.getLocale(); |
| } |
| |
| /** |
| * @return Bundle for this session |
| */ |
| public Bundle getBundle() { |
| return mInternalSession.getBundle(); |
| } |
| } |
| |
| // Preventing from exposing ISpellCheckerSession.aidl, create an internal class. |
| private static class InternalISpellCheckerSession extends ISpellCheckerSession.Stub { |
| private ISpellCheckerSessionListener mListener; |
| private final Session mSession; |
| private final String mLocale; |
| private final Bundle mBundle; |
| |
| public InternalISpellCheckerSession(String locale, ISpellCheckerSessionListener listener, |
| Bundle bundle, Session session) { |
| mListener = listener; |
| mSession = session; |
| mLocale = locale; |
| mBundle = bundle; |
| session.setInternalISpellCheckerSession(this); |
| } |
| |
| @Override |
| public void onGetSuggestionsMultiple( |
| TextInfo[] textInfos, int suggestionsLimit, boolean sequentialWords) { |
| int pri = Process.getThreadPriority(Process.myTid()); |
| try { |
| Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND); |
| mListener.onGetSuggestions( |
| mSession.onGetSuggestionsMultiple( |
| textInfos, suggestionsLimit, sequentialWords)); |
| } catch (RemoteException e) { |
| } finally { |
| Process.setThreadPriority(pri); |
| } |
| } |
| |
| @Override |
| public void onGetSentenceSuggestionsMultiple(TextInfo[] textInfos, int suggestionsLimit) { |
| try { |
| mListener.onGetSentenceSuggestions( |
| mSession.onGetSentenceSuggestionsMultiple(textInfos, suggestionsLimit)); |
| } catch (RemoteException e) { |
| } |
| } |
| |
| @Override |
| public void onCancel() { |
| int pri = Process.getThreadPriority(Process.myTid()); |
| try { |
| Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND); |
| mSession.onCancel(); |
| } finally { |
| Process.setThreadPriority(pri); |
| } |
| } |
| |
| @Override |
| public void onClose() { |
| int pri = Process.getThreadPriority(Process.myTid()); |
| try { |
| Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND); |
| mSession.onClose(); |
| } finally { |
| Process.setThreadPriority(pri); |
| mListener = null; |
| } |
| } |
| |
| public String getLocale() { |
| return mLocale; |
| } |
| |
| public Bundle getBundle() { |
| return mBundle; |
| } |
| } |
| |
| private static class SpellCheckerServiceBinder extends ISpellCheckerService.Stub { |
| private final WeakReference<SpellCheckerService> mInternalServiceRef; |
| |
| public SpellCheckerServiceBinder(SpellCheckerService service) { |
| mInternalServiceRef = new WeakReference<SpellCheckerService>(service); |
| } |
| |
| /** |
| * Called from the system when an application is requesting a new spell checker session. |
| * |
| * <p>Note: This is an internal protocol used by the system to establish spell checker |
| * sessions, which is not guaranteed to be stable and is subject to change.</p> |
| * |
| * @param locale locale to be returned from {@link Session#getLocale()} |
| * @param listener IPC channel object to be used to implement |
| * {@link Session#onGetSuggestionsMultiple(TextInfo[], int, boolean)} and |
| * {@link Session#onGetSuggestions(TextInfo, int)} |
| * @param bundle bundle to be returned from {@link Session#getBundle()} |
| * @param callback IPC channel to return the result to the caller in an asynchronous manner |
| */ |
| @Override |
| public void getISpellCheckerSession( |
| String locale, ISpellCheckerSessionListener listener, Bundle bundle, |
| ISpellCheckerServiceCallback callback) { |
| final SpellCheckerService service = mInternalServiceRef.get(); |
| final InternalISpellCheckerSession internalSession; |
| if (service == null) { |
| // If the owner SpellCheckerService object was already destroyed and got GC-ed, |
| // the weak-reference returns null and we should just ignore this request. |
| internalSession = null; |
| } else { |
| final Session session = service.createSession(); |
| internalSession = |
| new InternalISpellCheckerSession(locale, listener, bundle, session); |
| session.onCreate(); |
| } |
| try { |
| callback.onSessionCreated(internalSession); |
| } catch (RemoteException e) { |
| } |
| } |
| } |
| |
| /** |
| * Adapter class to accommodate word level spell checking APIs to sentence level spell checking |
| * APIs used in |
| * {@link SpellCheckerService.Session#onGetSuggestionsMultiple(TextInfo[], int, boolean)} |
| */ |
| private static class SentenceLevelAdapter { |
| public static final SentenceSuggestionsInfo[] EMPTY_SENTENCE_SUGGESTIONS_INFOS = |
| new SentenceSuggestionsInfo[] {}; |
| private static final SuggestionsInfo EMPTY_SUGGESTIONS_INFO = new SuggestionsInfo(0, null); |
| /** |
| * Container for split TextInfo parameters |
| */ |
| public static class SentenceWordItem { |
| public final TextInfo mTextInfo; |
| public final int mStart; |
| public final int mLength; |
| public SentenceWordItem(TextInfo ti, int start, int end) { |
| mTextInfo = ti; |
| mStart = start; |
| mLength = end - start; |
| } |
| } |
| |
| /** |
| * Container for originally queried TextInfo and parameters |
| */ |
| public static class SentenceTextInfoParams { |
| final TextInfo mOriginalTextInfo; |
| final ArrayList<SentenceWordItem> mItems; |
| final int mSize; |
| public SentenceTextInfoParams(TextInfo ti, ArrayList<SentenceWordItem> items) { |
| mOriginalTextInfo = ti; |
| mItems = items; |
| mSize = items.size(); |
| } |
| } |
| |
| private final WordIterator mWordIterator; |
| public SentenceLevelAdapter(Locale locale) { |
| mWordIterator = new WordIterator(locale); |
| } |
| |
| private SentenceTextInfoParams getSplitWords(TextInfo originalTextInfo) { |
| final WordIterator wordIterator = mWordIterator; |
| final CharSequence originalText = originalTextInfo.getText(); |
| final int cookie = originalTextInfo.getCookie(); |
| final int start = 0; |
| final int end = originalText.length(); |
| final ArrayList<SentenceWordItem> wordItems = new ArrayList<SentenceWordItem>(); |
| wordIterator.setCharSequence(originalText, 0, originalText.length()); |
| int wordEnd = wordIterator.following(start); |
| int wordStart = wordIterator.getBeginning(wordEnd); |
| if (DBG) { |
| Log.d(TAG, "iterator: break: ---- 1st word start = " + wordStart + ", end = " |
| + wordEnd + "\n" + originalText); |
| } |
| while (wordStart <= end && wordEnd != BreakIterator.DONE |
| && wordStart != BreakIterator.DONE) { |
| if (wordEnd >= start && wordEnd > wordStart) { |
| final CharSequence query = originalText.subSequence(wordStart, wordEnd); |
| final TextInfo ti = new TextInfo(query, 0, query.length(), cookie, |
| query.hashCode()); |
| wordItems.add(new SentenceWordItem(ti, wordStart, wordEnd)); |
| if (DBG) { |
| Log.d(TAG, "Adapter: word (" + (wordItems.size() - 1) + ") " + query); |
| } |
| } |
| wordEnd = wordIterator.following(wordEnd); |
| if (wordEnd == BreakIterator.DONE) { |
| break; |
| } |
| wordStart = wordIterator.getBeginning(wordEnd); |
| } |
| return new SentenceTextInfoParams(originalTextInfo, wordItems); |
| } |
| |
| public static SentenceSuggestionsInfo reconstructSuggestions( |
| SentenceTextInfoParams originalTextInfoParams, SuggestionsInfo[] results) { |
| if (results == null || results.length == 0) { |
| return null; |
| } |
| if (DBG) { |
| Log.w(TAG, "Adapter: onGetSuggestions: got " + results.length); |
| } |
| if (originalTextInfoParams == null) { |
| if (DBG) { |
| Log.w(TAG, "Adapter: originalTextInfoParams is null."); |
| } |
| return null; |
| } |
| final int originalCookie = originalTextInfoParams.mOriginalTextInfo.getCookie(); |
| final int originalSequence = |
| originalTextInfoParams.mOriginalTextInfo.getSequence(); |
| |
| final int querySize = originalTextInfoParams.mSize; |
| final int[] offsets = new int[querySize]; |
| final int[] lengths = new int[querySize]; |
| final SuggestionsInfo[] reconstructedSuggestions = new SuggestionsInfo[querySize]; |
| for (int i = 0; i < querySize; ++i) { |
| final SentenceWordItem item = originalTextInfoParams.mItems.get(i); |
| SuggestionsInfo result = null; |
| for (int j = 0; j < results.length; ++j) { |
| final SuggestionsInfo cur = results[j]; |
| if (cur != null && cur.getSequence() == item.mTextInfo.getSequence()) { |
| result = cur; |
| result.setCookieAndSequence(originalCookie, originalSequence); |
| break; |
| } |
| } |
| offsets[i] = item.mStart; |
| lengths[i] = item.mLength; |
| reconstructedSuggestions[i] = result != null ? result : EMPTY_SUGGESTIONS_INFO; |
| if (DBG) { |
| final int size = reconstructedSuggestions[i].getSuggestionsCount(); |
| Log.w(TAG, "reconstructedSuggestions(" + i + ")" + size + ", first = " |
| + (size > 0 ? reconstructedSuggestions[i].getSuggestionAt(0) |
| : "<none>") + ", offset = " + offsets[i] + ", length = " |
| + lengths[i]); |
| } |
| } |
| return new SentenceSuggestionsInfo(reconstructedSuggestions, offsets, lengths); |
| } |
| } |
| } |