diff --git a/java/src/com/android/inputmethod/latin/AbstractDictionaryWriter.java b/java/src/com/android/inputmethod/latin/AbstractDictionaryWriter.java
index 269b3a2..55df263 100644
--- a/java/src/com/android/inputmethod/latin/AbstractDictionaryWriter.java
+++ b/java/src/com/android/inputmethod/latin/AbstractDictionaryWriter.java
@@ -19,10 +19,11 @@
 import android.content.Context;
 import android.util.Log;
 
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
+import com.android.inputmethod.latin.makedict.Ver3DictEncoder;
 
 import java.io.File;
-import java.io.FileOutputStream;
 import java.io.IOException;
 
 // TODO: Quit extending Dictionary after implementing dynamic binary dictionary.
@@ -49,32 +50,21 @@
 
     abstract public void removeBigramWords(final String word0, final String word1);
 
-    abstract protected void writeBinaryDictionary(final FileOutputStream out)
+    abstract protected void writeDictionary(final DictEncoder dictEncoder)
             throws IOException, UnsupportedFormatException;
 
     public void write(final String fileName) {
         final String tempFileName = fileName + ".temp";
         final File file = new File(mContext.getFilesDir(), fileName);
         final File tempFile = new File(mContext.getFilesDir(), tempFileName);
-        FileOutputStream out = null;
         try {
-            out = new FileOutputStream(tempFile);
-            writeBinaryDictionary(out);
-            out.flush();
-            out.close();
+            final DictEncoder dictEncoder = new Ver3DictEncoder(file);
+            writeDictionary(dictEncoder);
             tempFile.renameTo(file);
         } catch (IOException e) {
             Log.e(TAG, "IO exception while writing file", e);
         } catch (UnsupportedFormatException e) {
             Log.e(TAG, "Unsupported format", e);
-        } finally {
-            if (out != null) {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    // ignore
-                }
-            }
         }
     }
 }
diff --git a/java/src/com/android/inputmethod/latin/DictionaryWriter.java b/java/src/com/android/inputmethod/latin/DictionaryWriter.java
index b3a5728..a97e053 100644
--- a/java/src/com/android/inputmethod/latin/DictionaryWriter.java
+++ b/java/src/com/android/inputmethod/latin/DictionaryWriter.java
@@ -20,7 +20,7 @@
 
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
-import com.android.inputmethod.latin.makedict.BinaryDictEncoderUtils;
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
@@ -28,7 +28,6 @@
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
 import com.android.inputmethod.latin.utils.CollectionUtils;
 
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -85,9 +84,9 @@
     }
 
     @Override
-    protected void writeBinaryDictionary(final FileOutputStream out)
+    protected void writeDictionary(final DictEncoder dictEncoder)
             throws IOException, UnsupportedFormatException {
-        BinaryDictEncoderUtils.writeDictionaryBinary(out, mFusionDictionary, FORMAT_OPTIONS);
+        dictEncoder.writeDictionary(mFusionDictionary, FORMAT_OPTIONS);
     }
 
     @Override
diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index d67195b..3a2de59 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -73,6 +73,7 @@
 import com.android.inputmethod.keyboard.MainKeyboardView;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 import com.android.inputmethod.latin.define.ProductionFlag;
+import com.android.inputmethod.latin.personalization.PersonalizationDictionary;
 import com.android.inputmethod.latin.personalization.PersonalizationDictionaryHelper;
 import com.android.inputmethod.latin.personalization.PersonalizationDictionarySessionRegister;
 import com.android.inputmethod.latin.personalization.PersonalizationPredictionDictionary;
@@ -173,6 +174,7 @@
     private UserBinaryDictionary mUserDictionary;
     private UserHistoryPredictionDictionary mUserHistoryPredictionDictionary;
     private PersonalizationPredictionDictionary mPersonalizationPredictionDictionary;
+    private PersonalizationDictionary mPersonalizationDictionary;
     private boolean mIsUserDictionaryAvailable;
 
     private LastComposedWord mLastComposedWord = LastComposedWord.NOT_A_COMPOSED_WORD;
@@ -567,6 +569,9 @@
         mUserHistoryPredictionDictionary = PersonalizationDictionaryHelper
                 .getUserHistoryPredictionDictionary(this, localeStr, prefs);
         newSuggest.setUserHistoryPredictionDictionary(mUserHistoryPredictionDictionary);
+        mPersonalizationDictionary = PersonalizationDictionaryHelper
+                .getPersonalizationDictionary(this, localeStr, prefs);
+        newSuggest.setPersonalizationDictionary(mPersonalizationDictionary);
         mPersonalizationPredictionDictionary = PersonalizationDictionaryHelper
                 .getPersonalizationPredictionDictionary(this, localeStr, prefs);
         newSuggest.setPersonalizationPredictionDictionary(mPersonalizationPredictionDictionary);
diff --git a/java/src/com/android/inputmethod/latin/Suggest.java b/java/src/com/android/inputmethod/latin/Suggest.java
index 8766e0f..c8a151a 100644
--- a/java/src/com/android/inputmethod/latin/Suggest.java
+++ b/java/src/com/android/inputmethod/latin/Suggest.java
@@ -24,6 +24,7 @@
 import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
+import com.android.inputmethod.latin.personalization.PersonalizationDictionary;
 import com.android.inputmethod.latin.personalization.PersonalizationPredictionDictionary;
 import com.android.inputmethod.latin.personalization.UserHistoryPredictionDictionary;
 import com.android.inputmethod.latin.settings.Settings;
@@ -200,6 +201,12 @@
                 personalizationPredictionDictionary);
     }
 
+    public void setPersonalizationDictionary(
+            final PersonalizationDictionary personalizationDictionary) {
+        addOrReplaceDictionaryInternal(Dictionary.TYPE_PERSONALIZATION,
+                personalizationDictionary);
+    }
+
     public void setAutoCorrectionThreshold(float threshold) {
         mAutoCorrectionThreshold = threshold;
     }
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java
index 3fe3ae6..40effb5 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java
@@ -108,7 +108,7 @@
      * like address lists do.
      */
     static int getShortcutListSize(final ArrayList<WeightedString> shortcutList) {
-        if (null == shortcutList) return 0;
+        if (null == shortcutList || shortcutList.isEmpty()) return 0;
         int size = FormatSpec.GROUP_SHORTCUT_LIST_SIZE_SIZE;
         for (final WeightedString shortcut : shortcutList) {
             size += getShortcutSize(shortcut);
@@ -601,8 +601,9 @@
     private static byte makeCharGroupFlags(final CharGroup group, final int groupAddress,
             final int childrenOffset, final FormatOptions formatOptions) {
         return (byte) makeCharGroupFlags(group.mChars.length > 1, group.mFrequency >= 0,
-                getByteSize(childrenOffset), group.mShortcutTargets != null, group.mBigrams != null,
-                group.mIsNotAWord, group.mIsBlacklistEntry, formatOptions);
+                getByteSize(childrenOffset),
+                group.mShortcutTargets != null && !group.mShortcutTargets.isEmpty(),
+                group.mBigrams != null, group.mIsNotAWord, group.mIsBlacklistEntry, formatOptions);
     }
 
     /**
@@ -795,7 +796,7 @@
             groupAddress += shift;
 
             // Write shortcuts
-            if (null != group.mShortcutTargets) {
+            if (null != group.mShortcutTargets && !group.mShortcutTargets.isEmpty()) {
                 final int indexOfShortcutByteSize = index;
                 index += FormatSpec.GROUP_SHORTCUT_LIST_SIZE_SIZE;
                 groupAddress += FormatSpec.GROUP_SHORTCUT_LIST_SIZE_SIZE;
@@ -911,13 +912,11 @@
     /**
      * Dumps a FusionDictionary to a file.
      *
-     * This is the public entry point to write a dictionary to a file.
-     *
      * @param destination the stream to write the binary data to.
      * @param dict the dictionary to write.
      * @param formatOptions file format options.
      */
-    public static void writeDictionaryBinary(final OutputStream destination,
+    /* package */ static void writeDictionaryBinary(final OutputStream destination,
             final FusionDictionary dict, final FormatOptions formatOptions)
             throws IOException, UnsupportedFormatException {
 
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
index 8e1e14e..9f8842c 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
@@ -375,7 +375,7 @@
      * @param info the char group info to be written.
      * @return the size written, in bytes.
      */
-    public static int writeCharGroup(final OutputStream destination, final CharGroupInfo info)
+    private static int writeCharGroup(final OutputStream destination, final CharGroupInfo info)
             throws IOException {
         int size = FormatSpec.GROUP_FLAGS_SIZE;
         destination.write((byte)info.mFlags);
@@ -507,29 +507,6 @@
         return size + FormatSpec.FORWARD_LINK_ADDRESS_SIZE;
     }
 
-    /**
-     * Find a word using the Ver3DictDecoder.
-     *
-     * @param dictDecoder the dict reader
-     * @param word the word searched
-     * @return the found group
-     * @throws IOException
-     * @throws UnsupportedFormatException
-     */
-    @UsedForTesting
-    public static CharGroupInfo findWordByBinaryDictReader(final Ver3DictDecoder dictDecoder,
-            final String word) throws IOException, UnsupportedFormatException {
-        int position = getTerminalPosition(dictDecoder, word);
-        final DictBuffer dictBuffer = dictDecoder.getDictBuffer();
-        if (position != FormatSpec.NOT_VALID_WORD) {
-            dictBuffer.position(0);
-            final FileHeader header = dictDecoder.readHeader();
-            dictBuffer.position(position);
-            return dictDecoder.readPtNode(position, header.mFormatOptions);
-        }
-        return null;
-    }
-
     private static final int HEADER_READING_BUFFER_SIZE = 16384;
     /**
      * Convenience method to read the header of a binary file.
diff --git a/java/src/com/android/inputmethod/latin/makedict/DictEncoder.java b/java/src/com/android/inputmethod/latin/makedict/DictEncoder.java
new file mode 100644
index 0000000..89c982e
--- /dev/null
+++ b/java/src/com/android/inputmethod/latin/makedict/DictEncoder.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2013 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.makedict;
+
+import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
+
+import java.io.IOException;
+
+/**
+ * An interface of binary dictionary encoder.
+ */
+public interface DictEncoder {
+    public void writeDictionary(final FusionDictionary dict, final FormatOptions formatOptions)
+            throws IOException, UnsupportedFormatException;
+}
diff --git a/java/src/com/android/inputmethod/latin/makedict/Ver3DictDecoder.java b/java/src/com/android/inputmethod/latin/makedict/Ver3DictDecoder.java
index 8d1b027..494bbfc 100644
--- a/java/src/com/android/inputmethod/latin/makedict/Ver3DictDecoder.java
+++ b/java/src/com/android/inputmethod/latin/makedict/Ver3DictDecoder.java
@@ -255,18 +255,26 @@
             childrenAddress += addressPointer;
         }
         addressPointer += BinaryDictIOUtils.getChildrenAddressSize(flags, options);
-        ArrayList<WeightedString> shortcutTargets = null;
+        final ArrayList<WeightedString> shortcutTargets;
         if (0 != (flags & FormatSpec.FLAG_HAS_SHORTCUT_TARGETS)) {
+            // readShortcut will add shortcuts to shortcutTargets.
+            shortcutTargets = new ArrayList<WeightedString>();
             addressPointer += PtNodeReader.readShortcut(mDictBuffer, shortcutTargets);
+        } else {
+            shortcutTargets = null;
         }
-        ArrayList<PendingAttribute> bigrams = null;
+
+        final ArrayList<PendingAttribute> bigrams;
         if (0 != (flags & FormatSpec.FLAG_HAS_BIGRAMS)) {
             bigrams = new ArrayList<PendingAttribute>();
             addressPointer += PtNodeReader.readBigrams(mDictBuffer, bigrams, addressPointer);
             if (bigrams.size() >= FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
                 MakedictLog.d("too many bigrams in a group.");
             }
+        } else {
+            bigrams = null;
         }
+
         return new CharGroupInfo(ptNodePos, addressPointer, flags, characters, frequency,
                 parentAddress, childrenAddress, shortcutTargets, bigrams);
     }
diff --git a/java/src/com/android/inputmethod/latin/makedict/Ver3DictEncoder.java b/java/src/com/android/inputmethod/latin/makedict/Ver3DictEncoder.java
new file mode 100644
index 0000000..e81fd45
--- /dev/null
+++ b/java/src/com/android/inputmethod/latin/makedict/Ver3DictEncoder.java
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2013 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.makedict;
+
+import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ * An implementation of DictEncoder for version 3 binary dictionary.
+ */
+public class Ver3DictEncoder implements DictEncoder {
+
+    private final File mDictFile;
+    private OutputStream mOutStream;
+
+    public Ver3DictEncoder(final File dictFile) {
+        mDictFile = dictFile;
+        mOutStream = null;
+    }
+
+    // This constructor is used only by BinaryDictOffdeviceUtilsTests.
+    // If you want to use this in the production code, you should consider keeping consistency of
+    // the interface of Ver3DictDecoder by using factory.
+    public Ver3DictEncoder(final OutputStream outStream) {
+        mDictFile = null;
+        mOutStream = outStream;
+    }
+
+    private void openStream() throws FileNotFoundException {
+        mOutStream = new FileOutputStream(mDictFile);
+    }
+
+    private void close() throws IOException {
+        if (mOutStream != null) {
+            mOutStream.close();
+            mOutStream = null;
+        }
+    }
+
+    @Override
+    public void writeDictionary(FusionDictionary dict, FormatOptions formatOptions)
+            throws IOException, UnsupportedFormatException {
+        if (mOutStream == null) {
+            openStream();
+        }
+        BinaryDictEncoderUtils.writeDictionaryBinary(mOutStream, dict, formatOptions);
+        close();
+    }
+}
diff --git a/java/src/com/android/inputmethod/latin/personalization/DynamicPredictionDictionaryBase.java b/java/src/com/android/inputmethod/latin/personalization/DynamicPredictionDictionaryBase.java
index b565b2f..d046da8 100644
--- a/java/src/com/android/inputmethod/latin/personalization/DynamicPredictionDictionaryBase.java
+++ b/java/src/com/android/inputmethod/latin/personalization/DynamicPredictionDictionaryBase.java
@@ -28,8 +28,10 @@
 import com.android.inputmethod.latin.LatinImeLogger;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 import com.android.inputmethod.latin.WordComposer;
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.Ver3DictDecoder;
+import com.android.inputmethod.latin.makedict.Ver3DictEncoder;
 import com.android.inputmethod.latin.settings.Settings;
 import com.android.inputmethod.latin.utils.CollectionUtils;
 import com.android.inputmethod.latin.utils.UserHistoryDictIOUtils;
@@ -40,7 +42,6 @@
 
 import java.io.File;
 import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.concurrent.atomic.AtomicReference;
@@ -332,24 +333,9 @@
             final String fileName =
                     mDynamicPredictionDictionary.getDictionaryFileName();
             final File file = new File(mContext.getFilesDir(), fileName);
-            FileOutputStream out = null;
 
-            try {
-                out = new FileOutputStream(file);
-                UserHistoryDictIOUtils.writeDictionaryBinary(out, this, mBigramList, VERSION3);
-                out.flush();
-                out.close();
-            } catch (IOException e) {
-                Log.e(TAG, "IO Exception while writing file", e);
-            } finally {
-                if (out != null) {
-                    try {
-                        out.close();
-                    } catch (IOException e) {
-                        // ignore
-                    }
-                }
-            }
+            final DictEncoder dictEncoder = new Ver3DictEncoder(file);
+            UserHistoryDictIOUtils.writeDictionary(dictEncoder, this, mBigramList, VERSION3);
 
             // Save the timestamp after we finish writing the binary dictionary.
             Settings.writeLastUserHistoryWriteTime(mPrefs, mLocale);
@@ -403,7 +389,7 @@
     }
 
     public void registerUpdateSession(PersonalizationDictionaryUpdateSession session) {
-        session.setPredictionDictionary(mLocale, this);
+        session.setPredictionDictionary(this);
         mSessions.add(session);
         session.onDictionaryReady();
     }
diff --git a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionary.java b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionary.java
index 275ce2f..f257165 100644
--- a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionary.java
+++ b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionary.java
@@ -18,28 +18,32 @@
 
 import com.android.inputmethod.latin.Dictionary;
 import com.android.inputmethod.latin.ExpandableBinaryDictionary;
+import com.android.inputmethod.latin.utils.CollectionUtils;
 
 import android.content.Context;
+import android.content.SharedPreferences;
+
+import java.util.ArrayList;
 
 /**
  * This class is a dictionary for the personalized language model that uses binary dictionary.
  */
 public class PersonalizationDictionary extends ExpandableBinaryDictionary {
     private static final String NAME = "personalization";
-
-    public static void registerUpdateListener(PersonalizationDictionaryUpdateSession listener) {
-        // TODO: Implement
-    }
+    private final ArrayList<PersonalizationDictionaryUpdateSession> mSessions =
+            CollectionUtils.newArrayList();
 
     /** Locale for which this user history dictionary is storing words */
     private final String mLocale;
 
-    // Singleton
-    private PersonalizationDictionary(final Context context, final String locale) {
+    public PersonalizationDictionary(final Context context, final String locale,
+            final SharedPreferences prefs) {
         // TODO: Make isUpdatable true.
         super(context, getFilenameWithLocale(NAME, locale), Dictionary.TYPE_PERSONALIZATION,
                 false /* isUpdatable */);
         mLocale = locale;
+        // TODO: Restore last updated time
+        loadDictionary();
     }
 
     @Override
@@ -49,15 +53,21 @@
 
     @Override
     protected boolean hasContentChanged() {
-        // TODO: Implement
         return false;
     }
 
     @Override
     protected boolean needsToReloadBeforeWriting() {
-        // TODO: Implement
         return false;
     }
 
-    // TODO: Implement
+    public void registerUpdateSession(PersonalizationDictionaryUpdateSession session) {
+        session.setDictionary(this);
+        mSessions.add(session);
+        session.onDictionaryReady();
+    }
+
+    public void unRegisterUpdateSession(PersonalizationDictionaryUpdateSession session) {
+        mSessions.remove(session);
+    }
 }
diff --git a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryHelper.java b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryHelper.java
index b4fd250..6798f136 100644
--- a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryHelper.java
+++ b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryHelper.java
@@ -35,7 +35,13 @@
 
     private static final ConcurrentHashMap<String,
             SoftReference<PersonalizationPredictionDictionary>>
-                    sLangPersonalizationDictCache = CollectionUtils.newConcurrentHashMap();
+                    sLangPersonalizationPredictionDictCache =
+                            CollectionUtils.newConcurrentHashMap();
+
+    private static final ConcurrentHashMap<String,
+            SoftReference<PersonalizationDictionary>>
+                    sLangPersonalizationDictCache =
+                            CollectionUtils.newConcurrentHashMap();
 
     public static UserHistoryPredictionDictionary getUserHistoryPredictionDictionary(
             final Context context, final String locale, final SharedPreferences sp) {
@@ -60,20 +66,45 @@
     }
 
     public static void registerPersonalizationDictionaryUpdateSession(final Context context,
-            final PersonalizationDictionaryUpdateSession session) {
-        final PersonalizationPredictionDictionary dictionary =
-                getPersonalizationPredictionDictionary(context,
-                        context.getResources().getConfiguration().locale.toString(),
+            final PersonalizationDictionaryUpdateSession session, String locale) {
+        final PersonalizationPredictionDictionary predictionDictionary =
+                getPersonalizationPredictionDictionary(context, locale,
+                        PreferenceManager.getDefaultSharedPreferences(context));
+        predictionDictionary.registerUpdateSession(session);
+        final PersonalizationDictionary dictionary =
+                getPersonalizationDictionary(context, locale,
                         PreferenceManager.getDefaultSharedPreferences(context));
         dictionary.registerUpdateSession(session);
     }
 
-    public static PersonalizationPredictionDictionary getPersonalizationPredictionDictionary(
+    public static PersonalizationDictionary getPersonalizationDictionary(
             final Context context, final String locale, final SharedPreferences sp) {
         synchronized (sLangPersonalizationDictCache) {
             if (sLangPersonalizationDictCache.containsKey(locale)) {
-                final SoftReference<PersonalizationPredictionDictionary> ref =
+                final SoftReference<PersonalizationDictionary> ref =
                         sLangPersonalizationDictCache.get(locale);
+                final PersonalizationDictionary dict = ref == null ? null : ref.get();
+                if (dict != null) {
+                    if (DEBUG) {
+                        Log.w(TAG, "Use cached PersonalizationDictCache for " + locale);
+                    }
+                    return dict;
+                }
+            }
+            final PersonalizationDictionary dict =
+                    new PersonalizationDictionary(context, locale, sp);
+            sLangPersonalizationDictCache.put(
+                    locale, new SoftReference<PersonalizationDictionary>(dict));
+            return dict;
+        }
+    }
+
+    public static PersonalizationPredictionDictionary getPersonalizationPredictionDictionary(
+            final Context context, final String locale, final SharedPreferences sp) {
+        synchronized (sLangPersonalizationPredictionDictCache) {
+            if (sLangPersonalizationPredictionDictCache.containsKey(locale)) {
+                final SoftReference<PersonalizationPredictionDictionary> ref =
+                        sLangPersonalizationPredictionDictCache.get(locale);
                 final PersonalizationPredictionDictionary dict = ref == null ? null : ref.get();
                 if (dict != null) {
                     if (DEBUG) {
@@ -84,7 +115,7 @@
             }
             final PersonalizationPredictionDictionary dict =
                     new PersonalizationPredictionDictionary(context, locale, sp);
-            sLangPersonalizationDictCache.put(
+            sLangPersonalizationPredictionDictCache.put(
                     locale, new SoftReference<PersonalizationPredictionDictionary>(dict));
             return dict;
         }
diff --git a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdateSession.java b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdateSession.java
index 77f0cdb..9788049 100644
--- a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdateSession.java
+++ b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdateSession.java
@@ -16,6 +16,8 @@
 
 package com.android.inputmethod.latin.personalization;
 
+import com.android.inputmethod.latin.ExpandableBinaryDictionary;
+
 import android.content.Context;
 
 import java.lang.ref.WeakReference;
@@ -45,22 +47,41 @@
     }
 
     // TODO: Use a dynamic binary dictionary instead
+    public WeakReference<PersonalizationDictionary> mDictionary;
     public WeakReference<DynamicPredictionDictionaryBase> mPredictionDictionary;
-    public String mLocale;
+    public final String mLocale;
+    public PersonalizationDictionaryUpdateSession(String locale) {
+        mLocale = locale;
+    }
 
     public abstract void onDictionaryReady();
 
     public abstract void onDictionaryClosed(Context context);
 
-    public void setPredictionDictionary(String locale, DynamicPredictionDictionaryBase dictionary) {
+    public void setDictionary(PersonalizationDictionary dictionary) {
+        mDictionary = new WeakReference<PersonalizationDictionary>(dictionary);
+    }
+
+    public void setPredictionDictionary(DynamicPredictionDictionaryBase dictionary) {
         mPredictionDictionary = new WeakReference<DynamicPredictionDictionaryBase>(dictionary);
-        mLocale = locale;
+    }
+
+    protected PersonalizationDictionary getDictionary() {
+        return mDictionary == null ? null : mDictionary.get();
     }
 
     protected DynamicPredictionDictionaryBase getPredictionDictionary() {
         return mPredictionDictionary == null ? null : mPredictionDictionary.get();
     }
 
+    private void unsetDictionary() {
+        final PersonalizationDictionary dictionary = getDictionary();
+        if (dictionary == null) {
+            return;
+        }
+        dictionary.unRegisterUpdateSession(this);
+    }
+
     private void unsetPredictionDictionary() {
         final DynamicPredictionDictionaryBase dictionary = getPredictionDictionary();
         if (dictionary == null) {
@@ -78,6 +99,7 @@
     }
 
     public void closeSession(Context context) {
+        unsetDictionary();
         unsetPredictionDictionary();
         onDictionaryClosed(context);
     }
diff --git a/java/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtils.java b/java/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtils.java
index 771db3a..9d3d8a5 100644
--- a/java/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtils.java
@@ -19,8 +19,8 @@
 import android.util.Log;
 
 import com.android.inputmethod.annotations.UsedForTesting;
-import com.android.inputmethod.latin.makedict.BinaryDictEncoderUtils;
 import com.android.inputmethod.latin.makedict.BinaryDictIOUtils;
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
@@ -30,7 +30,6 @@
 import com.android.inputmethod.latin.personalization.UserHistoryDictionaryBigramList;
 
 import java.io.IOException;
-import java.io.OutputStream;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Map;
@@ -57,12 +56,12 @@
     /**
      * Writes dictionary to file.
      */
-    public static void writeDictionaryBinary(final OutputStream destination,
+    public static void writeDictionary(final DictEncoder dictEncoder,
             final BigramDictionaryInterface dict, final UserHistoryDictionaryBigramList bigrams,
             final FormatOptions formatOptions) {
         final FusionDictionary fusionDict = constructFusionDictionary(dict, bigrams);
         try {
-            BinaryDictEncoderUtils.writeDictionaryBinary(destination, fusionDict, formatOptions);
+            dictEncoder.writeDictionary(fusionDict, formatOptions);
             Log.d(TAG, "end writing");
         } catch (IOException e) {
             Log.e(TAG, "IO exception while writing file", e);
diff --git a/native/jni/Android.mk b/native/jni/Android.mk
index a51fe3c..bf18897 100644
--- a/native/jni/Android.mk
+++ b/native/jni/Android.mk
@@ -71,14 +71,16 @@
         header/header_policy.cpp \
         header/header_reading_utils.cpp \
         shortcut/shortcut_list_reading_utils.cpp \
-        utils/byte_array_utils.cpp \
-        utils/format_utils.cpp \
         dictionary_structure_with_buffer_policy_factory.cpp \
         dynamic_patricia_trie_node_reader.cpp \
         dynamic_patricia_trie_policy.cpp \
         dynamic_patricia_trie_reading_utils.cpp \
         patricia_trie_policy.cpp \
         patricia_trie_reading_utils.cpp) \
+    $(addprefix suggest/policyimpl/dictionary/utils/, \
+        byte_array_utils.cpp \
+        extendable_buffer.cpp \
+        format_utils.cpp) \
     suggest/policyimpl/gesture/gesture_suggest_policy_factory.cpp \
     $(addprefix suggest/policyimpl/typing/, \
         scoring_params.cpp \
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h
index 8ba057b..0e5920f 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h
@@ -24,6 +24,7 @@
 #include "suggest/policyimpl/dictionary/bigram/bigram_list_policy.h"
 #include "suggest/policyimpl/dictionary/header/header_policy.h"
 #include "suggest/policyimpl/dictionary/shortcut/shortcut_list_policy.h"
+#include "suggest/policyimpl/dictionary/utils/extendable_buffer.h"
 #include "suggest/policyimpl/dictionary/utils/mmapped_buffer.h"
 
 namespace latinime {
@@ -34,7 +35,7 @@
 class DynamicPatriciaTriePolicy : public DictionaryStructureWithBufferPolicy {
  public:
     DynamicPatriciaTriePolicy(const MmappedBuffer *const buffer)
-            : mBuffer(buffer), mHeaderPolicy(mBuffer->getBuffer()),
+            : mBuffer(buffer), mExtendableBuffer(), mHeaderPolicy(mBuffer->getBuffer()),
               mDictRoot(mBuffer->getBuffer() + mHeaderPolicy.getSize()),
               mBigramListPolicy(mDictRoot), mShortcutListPolicy(mDictRoot) {}
 
@@ -87,8 +88,10 @@
     static const int MAX_CHILD_COUNT_TO_AVOID_INFINITE_LOOP;
 
     const MmappedBuffer *const mBuffer;
+    const ExtendableBuffer mExtendableBuffer;
     const HeaderPolicy mHeaderPolicy;
     // TODO: Consolidate mDictRoot.
+    // CAVEAT!: Be careful about array out of bound access with mDictRoot
     const uint8_t *const mDictRoot;
     const BigramListPolicy mBigramListPolicy;
     const ShortcutListPolicy mShortcutListPolicy;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/utils/extendable_buffer.cpp b/native/jni/src/suggest/policyimpl/dictionary/utils/extendable_buffer.cpp
new file mode 100644
index 0000000..e55cc24
--- /dev/null
+++ b/native/jni/src/suggest/policyimpl/dictionary/utils/extendable_buffer.cpp
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#include "suggest/policyimpl/dictionary/utils/extendable_buffer.h"
+
+namespace latinime {
+
+const size_t ExtendableBuffer::INITIAL_BUFFER_SIZE = 16 * 1024;
+const size_t ExtendableBuffer::MAX_BUFFER_SIZE = 1024 * 1024;
+const size_t ExtendableBuffer::EXTEND_BUFFER_SIZE_STEP = 16 * 1024;
+
+}
diff --git a/native/jni/src/suggest/policyimpl/dictionary/utils/extendable_buffer.h b/native/jni/src/suggest/policyimpl/dictionary/utils/extendable_buffer.h
new file mode 100644
index 0000000..d902d19
--- /dev/null
+++ b/native/jni/src/suggest/policyimpl/dictionary/utils/extendable_buffer.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2013, 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.
+ */
+
+#ifndef LATINIME_EXTENDABLE_BUFFER_H
+#define LATINIME_EXTENDABLE_BUFFER_H
+
+#include <cstddef>
+#include <stdint.h>
+#include <vector>
+
+#include "defines.h"
+
+namespace latinime {
+
+// This is used as a buffer that can be extended for updatable dictionaries.
+class ExtendableBuffer {
+ public:
+    ExtendableBuffer() : mBuffer(INITIAL_BUFFER_SIZE), mUsedSize(0) {}
+
+   AK_FORCE_INLINE uint8_t *getBuffer() {
+        return  &mBuffer[0];
+    }
+
+    // Return if the buffer is successfully extended or not.
+   AK_FORCE_INLINE bool extendBuffer() {
+        if (mBuffer.size() + EXTEND_BUFFER_SIZE_STEP > MAX_BUFFER_SIZE) {
+            return false;
+        }
+        mBuffer.resize(mBuffer.size() + EXTEND_BUFFER_SIZE_STEP);
+        return true;
+    }
+
+    AK_FORCE_INLINE int getAllocatedSize() const {
+        return mBuffer.size();
+    }
+
+    AK_FORCE_INLINE int getUsedSize() const {
+        return mUsedSize;
+    }
+
+    AK_FORCE_INLINE void clear() {
+        mUsedSize = 0;
+        mBuffer.clear();
+    }
+
+ private:
+    DISALLOW_COPY_AND_ASSIGN(ExtendableBuffer);
+
+    static const size_t INITIAL_BUFFER_SIZE;
+    static const size_t MAX_BUFFER_SIZE;
+    static const size_t EXTEND_BUFFER_SIZE_STEP;
+
+    std::vector<uint8_t> mBuffer;
+    int mUsedSize;
+};
+}
+#endif /* LATINIME_MMAPED_BUFFER_H */
diff --git a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java
index f30be97..5bf9143 100644
--- a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java
+++ b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java
@@ -22,19 +22,21 @@
 import android.util.Log;
 import android.util.SparseArray;
 
+import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils.CharEncoding;
 import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils.DictBuffer;
 import com.android.inputmethod.latin.makedict.FormatSpec.FileHeader;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
 import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
+import com.android.inputmethod.latin.utils.ByteArrayDictBuffer;
 import com.android.inputmethod.latin.utils.CollectionUtils;
 
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -54,6 +56,8 @@
     private static final int UNIGRAM_FREQ = 10;
     private static final int BIGRAM_FREQ = 50;
     private static final int TOLERANCE_OF_BIGRAM_FREQ = 5;
+    private static final int NUM_OF_NODES_HAVING_SHORTCUTS = 50;
+    private static final int NUM_OF_SHORTCUTS = 5;
 
     private static final int USE_BYTE_ARRAY = 1;
     private static final int USE_BYTE_BUFFER = 2;
@@ -64,6 +68,7 @@
     private static final SparseArray<List<Integer>> sStarBigrams = CollectionUtils.newSparseArray();
     private static final SparseArray<List<Integer>> sChainBigrams =
             CollectionUtils.newSparseArray();
+    private static final Map<String, List<String>> sShortcuts = CollectionUtils.newHashMap();
 
     private static final FormatSpec.FormatOptions VERSION2 = new FormatSpec.FormatOptions(2);
     private static final FormatSpec.FormatOptions VERSION3_WITHOUT_DYNAMIC_UPDATE =
@@ -96,6 +101,16 @@
         for (int i = 1; i < sWords.size(); ++i) {
             sStarBigrams.get(0).add(i);
         }
+
+        sShortcuts.clear();
+        for (int i = 0; i < NUM_OF_NODES_HAVING_SHORTCUTS; ++i) {
+            final int from = Math.abs(random.nextInt()) % sWords.size();
+            sShortcuts.put(sWords.get(from), new ArrayList<String>());
+            for (int j = 0; j < NUM_OF_SHORTCUTS; ++j) {
+                final int to = Math.abs(random.nextInt()) % sWords.size();
+                sShortcuts.get(sWords.get(from)).add(sWords.get(to));
+            }
+        }
     }
 
     private int[] generateCodePointSet(final int codePointSetSize, final Random random) {
@@ -105,7 +120,7 @@
             if (r < 0) continue;
             // Don't insert 0~0x20, but insert any other code point.
             // Code points are in the range 0~0x10FFFF.
-            final int candidateCodePoint = (int)(0x20 + r % (Character.MAX_CODE_POINT - 0x20));
+            final int candidateCodePoint = 0x20 + r % (Character.MAX_CODE_POINT - 0x20);
             // Code points between MIN_ and MAX_SURROGATE are not valid on their own.
             if (candidateCodePoint >= Character.MIN_SURROGATE
                     && candidateCodePoint <= Character.MAX_SURROGATE) continue;
@@ -204,17 +219,14 @@
         long now = -1, diff = -1;
 
         try {
-            final FileOutputStream out = new FileOutputStream(file);
+            final DictEncoder dictEncoder = new Ver3DictEncoder(file);
 
             now = System.currentTimeMillis();
             // If you need to dump the dict to a textual file, uncomment the line below and the
             // function above
             // dumpToCombinedFileForDebug(file, "/tmp/foo");
-            BinaryDictEncoderUtils.writeDictionaryBinary(out, dict, formatOptions);
+            dictEncoder.writeDictionary(dict, formatOptions);
             diff = System.currentTimeMillis() - now;
-
-            out.flush();
-            out.close();
         } catch (IOException e) {
             Log.e(TAG, "IO exception while writing file", e);
         } catch (UnsupportedFormatException e) {
@@ -247,6 +259,7 @@
         // check shortcut
         if (shortcutMap != null) {
             for (final Map.Entry<String, List<String>> entry : shortcutMap.entrySet()) {
+                assertTrue(words.contains(entry.getKey()));
                 final CharGroup group = FusionDictionary.findWordInTree(dict.mRootNodeArray,
                         entry.getKey());
                 for (final String word : entry.getValue()) {
@@ -325,6 +338,28 @@
                 formatOptions, "chain"));
         results.add(runReadAndWrite(sWords, sStarBigrams, null /* shortcuts */, bufferType,
                 formatOptions, "star"));
+        results.add(runReadAndWrite(sWords, sEmptyBigrams, sShortcuts, bufferType, formatOptions,
+                "unigram with shortcuts"));
+        results.add(runReadAndWrite(sWords, sChainBigrams, sShortcuts, bufferType, formatOptions,
+                "chain with shortcuts"));
+        results.add(runReadAndWrite(sWords, sStarBigrams, sShortcuts, bufferType, formatOptions,
+                "star with shortcuts"));
+    }
+
+    // Unit test for CharEncoding.readString and CharEncoding.writeString.
+    public void testCharEncoding() {
+        // the max length of a word in sWords is less than 50.
+        // See generateWords.
+        final byte[] buffer = new byte[50 * 3];
+        final DictBuffer dictBuffer = new ByteArrayDictBuffer(buffer);
+        for (final String word : sWords) {
+            Log.d("testReadAndWriteString", "write : " + word);
+            Arrays.fill(buffer, (byte)0);
+            CharEncoding.writeString(buffer, 0, word);
+            dictBuffer.position(0);
+            final String str = CharEncoding.readString(dictBuffer);
+            assertEquals(word, str);
+        }
     }
 
     public void testReadAndWriteWithByteBuffer() {
diff --git a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtilsTests.java b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtilsTests.java
index 68976a7..bfdc040 100644
--- a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtilsTests.java
+++ b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtilsTests.java
@@ -161,13 +161,35 @@
         return position;
     }
 
+    /**
+     * Find a word using the Ver3DictDecoder.
+     *
+     * @param dictDecoder the dict decoder
+     * @param word the word searched
+     * @return the found group
+     * @throws IOException
+     * @throws UnsupportedFormatException
+     */
+    private static CharGroupInfo findWordByBinaryDictReader(final Ver3DictDecoder dictDecoder,
+            final String word) throws IOException, UnsupportedFormatException {
+        int position = BinaryDictIOUtils.getTerminalPosition(dictDecoder, word);
+        final DictBuffer dictBuffer = dictDecoder.getDictBuffer();
+        if (position != FormatSpec.NOT_VALID_WORD) {
+            dictBuffer.position(0);
+            final FileHeader header = dictDecoder.readHeader();
+            dictBuffer.position(position);
+            return dictDecoder.readPtNode(position, header.mFormatOptions);
+        }
+        return null;
+    }
+
     private CharGroupInfo findWordFromFile(final File file, final String word) {
         final Ver3DictDecoder dictDecoder = new Ver3DictDecoder(file);
         CharGroupInfo info = null;
         try {
             dictDecoder.openDictBuffer(
                     new Ver3DictDecoder.DictionaryBufferFromReadOnlyByteBufferFactory());
-            info = BinaryDictIOUtils.findWordByBinaryDictReader(dictDecoder, word);
+            info = findWordByBinaryDictReader(dictDecoder, word);
         } catch (IOException e) {
         } catch (UnsupportedFormatException e) {
         }
@@ -252,9 +274,8 @@
         dict.add("abcd", 10, null, false);
 
         try {
-            final FileOutputStream out = new FileOutputStream(file);
-            BinaryDictEncoderUtils.writeDictionaryBinary(out, dict, FORMAT_OPTIONS);
-            out.close();
+            final DictEncoder dictEncoder = new Ver3DictEncoder(file);
+            dictEncoder.writeDictionary(dict, FORMAT_OPTIONS);
         } catch (IOException e) {
             fail("IOException while writing an initial dictionary : " + e);
         } catch (UnsupportedFormatException e) {
@@ -304,9 +325,8 @@
         dict.add("efgh", 15, null, false);
 
         try {
-            final FileOutputStream out = new FileOutputStream(file);
-            BinaryDictEncoderUtils.writeDictionaryBinary(out, dict, FORMAT_OPTIONS);
-            out.close();
+            final DictEncoder dictEncoder = new Ver3DictEncoder(file); 
+            dictEncoder.writeDictionary(dict, FORMAT_OPTIONS);
         } catch (IOException e) {
             fail("IOException while writing an initial dictionary : " + e);
         } catch (UnsupportedFormatException e) {
@@ -342,9 +362,8 @@
         dict.add("initial", 10, null, false);
 
         try {
-            final FileOutputStream out = new FileOutputStream(file);
-            BinaryDictEncoderUtils.writeDictionaryBinary(out, dict, FORMAT_OPTIONS);
-            out.close();
+            final DictEncoder dictEncoder = new Ver3DictEncoder(file);
+            dictEncoder.writeDictionary(dict, FORMAT_OPTIONS);
         } catch (IOException e) {
             assertTrue(false);
         } catch (UnsupportedFormatException e) {
diff --git a/tests/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtilsTests.java b/tests/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtilsTests.java
index eca12c0..7b3a01c 100644
--- a/tests/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtilsTests.java
+++ b/tests/src/com/android/inputmethod/latin/utils/UserHistoryDictIOUtilsTests.java
@@ -21,17 +21,18 @@
 import android.test.suitebuilder.annotation.LargeTest;
 import android.util.Log;
 
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
 import com.android.inputmethod.latin.makedict.Ver3DictDecoder;
+import com.android.inputmethod.latin.makedict.Ver3DictEncoder;
 import com.android.inputmethod.latin.personalization.UserHistoryDictionaryBigramList;
 import com.android.inputmethod.latin.utils.UserHistoryDictIOUtils.BigramDictionaryInterface;
 import com.android.inputmethod.latin.utils.UserHistoryDictIOUtils.OnAddWordListener;
 
 import java.io.File;
 import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -136,14 +137,8 @@
 
     private void writeDictToFile(final File file,
             final UserHistoryDictionaryBigramList bigramList) {
-        try {
-            final FileOutputStream out = new FileOutputStream(file);
-            UserHistoryDictIOUtils.writeDictionaryBinary(out, this, bigramList, FORMAT_OPTIONS);
-            out.flush();
-            out.close();
-        } catch (IOException e) {
-            Log.e(TAG, "IO exception while writing file", e);
-        }
+        final DictEncoder dictEncoder = new Ver3DictEncoder(file);
+        UserHistoryDictIOUtils.writeDictionary(dictEncoder, this, bigramList, FORMAT_OPTIONS);
     }
 
     private void readDictFromFile(final File file, final OnAddWordListener listener) {
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java
index fee4453..6c1a9de 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java
@@ -17,18 +17,18 @@
 package com.android.inputmethod.latin.dicttool;
 
 import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils;
-import com.android.inputmethod.latin.makedict.BinaryDictEncoderUtils;
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.MakedictLog;
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
 import com.android.inputmethod.latin.makedict.Ver3DictDecoder;
+import com.android.inputmethod.latin.makedict.Ver3DictEncoder;
 
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.util.Arrays;
@@ -358,8 +358,8 @@
             throws FileNotFoundException, IOException, UnsupportedFormatException {
         final File outputFile = new File(outputFilename);
         final FormatSpec.FormatOptions formatOptions = new FormatSpec.FormatOptions(version);
-        BinaryDictEncoderUtils.writeDictionaryBinary(new FileOutputStream(outputFilename), dict,
-                formatOptions);
+        final DictEncoder dictEncoder = new Ver3DictEncoder(outputFile);
+        dictEncoder.writeDictionary(dict, formatOptions);
     }
 
     /**
diff --git a/tools/dicttool/tests/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtilsTests.java b/tools/dicttool/tests/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtilsTests.java
index da51387..2b2661a 100644
--- a/tools/dicttool/tests/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtilsTests.java
+++ b/tools/dicttool/tests/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtilsTests.java
@@ -17,13 +17,14 @@
 package com.android.inputmethod.latin.dicttool;
 
 import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils;
-import com.android.inputmethod.latin.makedict.BinaryDictEncoderUtils;
+import com.android.inputmethod.latin.makedict.DictEncoder;
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.DictionaryOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
 import com.android.inputmethod.latin.makedict.Ver3DictDecoder;
+import com.android.inputmethod.latin.makedict.Ver3DictEncoder;
 
 import junit.framework.TestCase;
 
@@ -53,12 +54,13 @@
 
         final File dst = File.createTempFile("testGetRawDict", ".tmp");
         dst.deleteOnExit();
+
         final OutputStream out = Compress.getCompressedStream(
                 Compress.getCompressedStream(
                         Compress.getCompressedStream(
                                 new BufferedOutputStream(new FileOutputStream(dst)))));
-
-        BinaryDictEncoderUtils.writeDictionaryBinary(out, dict, new FormatOptions(2, false));
+        final DictEncoder dictEncoder = new Ver3DictEncoder(out);
+        dictEncoder.writeDictionary(dict, new FormatOptions(2, false));
 
         // Test for an actually compressed dictionary and its contents
         final BinaryDictOffdeviceUtils.DecoderChainSpec decodeSpec =