Implement the common Dictionary interface (A89)

This will de-duplicate a lot of existing code.

Change-Id: Idaffb2fde23b9741f057bcb2ecb3dde9d12ea5c5

java/src/com/android/inputmethod/latin/BinaryDictionary.java

@@ -105,6 +105,17 @@ public class BinaryDictionary extends Dictionary {
                 TYPED_LETTER_MULTIPLIER, FULL_WORD_SCORE_MULTIPLIER, MAX_WORD_LENGTH, MAX_WORDS);
     }
 
+    @Override
+    public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
+            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+        if (composer.size() <= 1) {
+            return TextUtils.isEmpty(prevWord) ? null : getBigrams(composer, prevWord);
+        } else {
+            return getWords(composer, prevWord, proximityInfo);
+        }
+    }
+
+    // TODO: rename this to getBigramsInternal, then move to native code
     @Override
     protected ArrayList<SuggestedWordInfo> getBigrams(final WordComposer codes,
             final CharSequence previousWord) {
@@ -143,6 +154,7 @@ public class BinaryDictionary extends Dictionary {
         return suggestions;
     }
 
+    // TODO: rename this to getWordsInternal, then move to native code
     // proximityInfo and/or prevWordForBigrams may not be null.
     @Override
     protected ArrayList<SuggestedWordInfo> getWords(final WordComposer codes,

java/src/com/android/inputmethod/latin/Dictionary.java

@@ -61,14 +61,8 @@ public abstract class Dictionary {
      */
     // TODO: pass more context than just the previous word, to enable better suggestions (n-gram
     // and more)
-    public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
+    abstract public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+            final CharSequence prevWord, final ProximityInfo proximityInfo);
-        if (composer.size() <= 1) {
-            return TextUtils.isEmpty(prevWord) ? null : getBigrams(composer, prevWord);
-        } else {
-            return getWords(composer, prevWord, proximityInfo);
-        }
-    }
 
     /**
      * Searches for words in the dictionary that match the characters in the composer. Matched
@@ -78,6 +72,7 @@ public abstract class Dictionary {
      * @param proximityInfo the object for key proximity. May be ignored by some implementations.
      * @return the list of suggestions
      */
+    // TODO: remove this
     abstract protected ArrayList<SuggestedWordInfo> getWords(final WordComposer composer,
             final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo);
 
@@ -87,6 +82,7 @@ public abstract class Dictionary {
      * @param previousWord the word before
      * @return the list of suggestions
      */
+    // TODO: remove this
     abstract protected ArrayList<SuggestedWordInfo> getBigrams(final WordComposer composer,
             final CharSequence previousWord);
 

java/src/com/android/inputmethod/latin/DictionaryCollection.java

@@ -54,6 +54,26 @@ public class DictionaryCollection extends Dictionary {
         mDictionaries.removeAll(Collections.singleton(null));
     }
 
+    @Override
+    public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
+            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+        final CopyOnWriteArrayList<Dictionary> dictionaries = mDictionaries;
+        if (dictionaries.isEmpty()) return null;
+        // To avoid creating unnecessary objects, we get the list out of the first
+        // dictionary and add the rest to it if not null, hence the get(0)
+        ArrayList<SuggestedWordInfo> suggestions = dictionaries.get(0).getSuggestions(composer,
+                prevWord, proximityInfo);
+        if (null == suggestions) suggestions = new ArrayList<SuggestedWordInfo>();
+        final int length = dictionaries.size();
+        for (int i = 0; i < length; ++ i) {
+            final ArrayList<SuggestedWordInfo> sugg = dictionaries.get(i).getSuggestions(composer,
+                    prevWord, proximityInfo);
+            if (null != sugg) suggestions.addAll(sugg);
+        }
+        return suggestions;
+    }
+
+    // TODO: remove this
     @Override
     protected ArrayList<SuggestedWordInfo> getWords(final WordComposer composer,
             final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo) {
@@ -73,6 +93,7 @@ public class DictionaryCollection extends Dictionary {
         return suggestions;
     }
 
+    // TODO: remove this
     @Override
     protected ArrayList<SuggestedWordInfo> getBigrams(final WordComposer composer,
             final CharSequence previousWord) {

java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java

@@ -16,6 +16,7 @@ package com.android.inputmethod.latin;
 
 import android.content.Context;
 import android.os.SystemClock;
+import android.text.TextUtils;
 import android.util.Log;
 
 import com.android.inputmethod.keyboard.ProximityInfo;
@@ -191,6 +192,23 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
         mFusionDictionary.setBigram(prevWord, word, frequency);
     }
 
+    @Override
+    public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
+            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+        asyncReloadDictionaryIfRequired();
+        if (mLocalDictionaryController.tryLock()) {
+            try {
+                if (mBinaryDictionary != null) {
+                    return mBinaryDictionary.getSuggestions(composer, prevWord, proximityInfo);
+                }
+            } finally {
+                mLocalDictionaryController.unlock();
+            }
+        }
+        return null;
+    }
+
+    // TODO: remove this
     @Override
     protected ArrayList<SuggestedWordInfo> getWords(final WordComposer codes,
             final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo) {
@@ -214,6 +232,7 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
         return null;
     }
 
+    // TODO: remove this
     @Override
     protected ArrayList<SuggestedWordInfo> getBigrams(final WordComposer codes,
             final CharSequence previousWord) {

java/src/com/android/inputmethod/latin/ExpandableDictionary.java

@@ -17,6 +17,7 @@
 package com.android.inputmethod.latin;
 
 import android.content.Context;
+import android.text.TextUtils;
 
 import com.android.inputmethod.keyboard.KeyDetector;
 import com.android.inputmethod.keyboard.Keyboard;
@@ -246,6 +247,26 @@ public class ExpandableDictionary extends Dictionary {
         addWordRec(childNode.mChildren, word, depth + 1, shortcutTarget, frequency, childNode);
     }
 
+    @Override
+    public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
+            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+        if (reloadDictionaryIfRequired()) return null;
+        if (composer.size() <= 1) {
+            if (composer.size() >= BinaryDictionary.MAX_WORD_LENGTH) {
+                return null;
+            }
+            final ArrayList<SuggestedWordInfo> suggestions =
+                    getWordsInner(composer, prevWord, proximityInfo);
+            return suggestions;
+        } else {
+            if (TextUtils.isEmpty(prevWord)) return null;
+            final ArrayList<SuggestedWordInfo> suggestions = new ArrayList<SuggestedWordInfo>();
+            runBigramReverseLookUp(prevWord, suggestions);
+            return suggestions;
+        }
+    }
+
+    // TODO: remove this
     @Override
     protected ArrayList<SuggestedWordInfo> getWords(final WordComposer codes,
             final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo) {
@@ -269,6 +290,7 @@ public class ExpandableDictionary extends Dictionary {
         }
     }
 
+    // TODO: remove this
     @Override
     protected ArrayList<SuggestedWordInfo> getBigrams(final WordComposer codes,
             final CharSequence previousWord) {