diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
index 877fff2..2e6c4b2 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
@@ -87,7 +87,7 @@
 
             if (p.mNumOfCharGroup == Position.NOT_READ_GROUPCOUNT) {
                 p.mNumOfCharGroup = BinaryDictInputOutput.readCharGroupCount(buffer);
-                p.mAddress += BinaryDictInputOutput.getGroupCountSize(p.mNumOfCharGroup);
+                p.mAddress += getGroupCountSize(p.mNumOfCharGroup);
                 p.mPosition = 0;
             }
             if (p.mNumOfCharGroup == 0) {
@@ -101,9 +101,9 @@
             }
             p.mPosition++;
 
-            final boolean isMovedGroup = BinaryDictInputOutput.isMovedGroup(info.mFlags,
+            final boolean isMovedGroup = isMovedGroup(info.mFlags,
                     formatOptions);
-            final boolean isDeletedGroup = BinaryDictInputOutput.isDeletedGroup(info.mFlags,
+            final boolean isDeletedGroup = isDeletedGroup(info.mFlags,
                     formatOptions);
             if (!isMovedGroup && !isDeletedGroup
                     && info.mFrequency != FusionDictionary.CharGroup.NOT_A_TERMINAL) {// found word
@@ -130,7 +130,7 @@
                 p.mAddress = buffer.position();
             }
 
-            if (!isMovedGroup && BinaryDictInputOutput.hasChildrenAddress(info.mChildrenAddress)) {
+            if (!isMovedGroup && hasChildrenAddress(info.mChildrenAddress)) {
                 Position childrenPos = new Position(info.mChildrenAddress + headerSize, index);
                 stack.push(childrenPos);
             }
@@ -187,12 +187,10 @@
                     final int charGroupPos = buffer.position();
                     final CharGroupInfo currentInfo = BinaryDictInputOutput.readCharGroup(buffer,
                             buffer.position(), header.mFormatOptions);
-                    final boolean isMovedGroup =
-                            BinaryDictInputOutput.isMovedGroup(currentInfo.mFlags,
-                                    header.mFormatOptions);
-                    final boolean isDeletedGroup =
-                            BinaryDictInputOutput.isDeletedGroup(currentInfo.mFlags,
-                                    header.mFormatOptions);
+                    final boolean isMovedGroup = isMovedGroup(currentInfo.mFlags,
+                            header.mFormatOptions);
+                    final boolean isDeletedGroup = isDeletedGroup(currentInfo.mFlags,
+                            header.mFormatOptions);
                     if (isMovedGroup) continue;
                     boolean same = true;
                     for (int p = 0, j = word.offsetByCodePoints(0, wordPos);
@@ -490,8 +488,8 @@
      */
     static int writeNode(final OutputStream destination, final CharGroupInfo[] infos)
             throws IOException {
-        int size = BinaryDictInputOutput.getGroupCountSize(infos.length);
-        switch (BinaryDictInputOutput.getGroupCountSize(infos.length)) {
+        int size = getGroupCountSize(infos.length);
+        switch (getGroupCountSize(infos.length)) {
             case 1:
                 destination.write((byte)infos.length);
                 break;
@@ -566,4 +564,52 @@
             return null;
         }
     }
+
+    /**
+     * Helper method to hide the actual value of the no children address.
+     */
+    public static boolean hasChildrenAddress(final int address) {
+        return FormatSpec.NO_CHILDREN_ADDRESS != address;
+    }
+
+    /**
+     * Helper method to check whether the group is moved.
+     */
+    public static boolean isMovedGroup(final int flags, final FormatOptions options) {
+        return options.mSupportsDynamicUpdate
+                && ((flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) == FormatSpec.FLAG_IS_MOVED);
+    }
+
+    /**
+     * Helper method to check whether the dictionary can be updated dynamically.
+     */
+    public static boolean supportsDynamicUpdate(final FormatOptions options) {
+        return options.mVersion >= FormatSpec.FIRST_VERSION_WITH_DYNAMIC_UPDATE
+                && options.mSupportsDynamicUpdate;
+    }
+
+    /**
+     * Helper method to check whether the group is deleted.
+     */
+    public static boolean isDeletedGroup(final int flags, final FormatOptions formatOptions) {
+        return formatOptions.mSupportsDynamicUpdate
+                && ((flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) == FormatSpec.FLAG_IS_DELETED);
+    }
+
+    /**
+     * Compute the binary size of the group count
+     * @param count the group count
+     * @return the size of the group count, either 1 or 2 bytes.
+     */
+    public static int getGroupCountSize(final int count) {
+        if (FormatSpec.MAX_CHARGROUPS_FOR_ONE_BYTE_CHARGROUP_COUNT >= count) {
+            return 1;
+        } else if (FormatSpec.MAX_CHARGROUPS_IN_A_NODE >= count) {
+            return 2;
+        } else {
+            throw new RuntimeException("Can't have more than "
+                    + FormatSpec.MAX_CHARGROUPS_IN_A_NODE + " groups in a node (found " + count
+                    + ")");
+        }
+    }
 }
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
index 5710e14..a546610 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
@@ -307,29 +307,12 @@
     }
 
     /**
-     * Compute the binary size of the group count
-     * @param count the group count
-     * @return the size of the group count, either 1 or 2 bytes.
-     */
-    public static int getGroupCountSize(final int count) {
-        if (FormatSpec.MAX_CHARGROUPS_FOR_ONE_BYTE_CHARGROUP_COUNT >= count) {
-            return 1;
-        } else if (FormatSpec.MAX_CHARGROUPS_IN_A_NODE >= count) {
-            return 2;
-        } else {
-            throw new RuntimeException("Can't have more than "
-                    + FormatSpec.MAX_CHARGROUPS_IN_A_NODE + " groups in a node (found " + count
-                    + ")");
-        }
-    }
-
-    /**
      * Compute the binary size of the group count for a node
      * @param node the node
      * @return the size of the group count, either 1 or 2 bytes.
      */
     private static int getGroupCountSize(final Node node) {
-        return getGroupCountSize(node.mData.size());
+        return BinaryDictIOUtils.getGroupCountSize(node.mData.size());
     }
 
     /**
@@ -404,44 +387,13 @@
     }
 
     /**
-     * Helper method to hide the actual value of the no children address.
-     */
-    public static boolean hasChildrenAddress(final int address) {
-        return FormatSpec.NO_CHILDREN_ADDRESS != address;
-    }
-
-    /**
-     * Helper method to check whether the group is moved.
-     */
-    public static boolean isMovedGroup(final int flags, final FormatOptions options) {
-        return options.mSupportsDynamicUpdate
-                && ((flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) == FormatSpec.FLAG_IS_MOVED);
-    }
-
-    /**
-     * Helper method to check whether the group is deleted.
-     */
-    public static boolean isDeletedGroup(final int flags, final FormatOptions formatOptions) {
-        return formatOptions.mSupportsDynamicUpdate
-                && ((flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) == FormatSpec.FLAG_IS_DELETED);
-    }
-
-    /**
-     * Helper method to check whether the dictionary can be updated dynamically.
-     */
-    public static boolean supportsDynamicUpdate(final FormatOptions options) {
-        return options.mVersion >= FormatSpec.FIRST_VERSION_WITH_DYNAMIC_UPDATE
-                && options.mSupportsDynamicUpdate;
-    }
-
-    /**
      * Compute the size of the header (flag + [parent address] + characters size) of a CharGroup.
      *
      * @param group the group of which to compute the size of the header
      * @param options file format options.
      */
     private static int getGroupHeaderSize(final CharGroup group, final FormatOptions options) {
-        if (supportsDynamicUpdate(options)) {
+        if (BinaryDictIOUtils.supportsDynamicUpdate(options)) {
             return FormatSpec.GROUP_FLAGS_SIZE + FormatSpec.PARENT_ADDRESS_SIZE
                     + getGroupCharactersSize(group);
         } else {
@@ -461,7 +413,7 @@
      */
     static int getByteSize(final int address) {
         assert(address <= FormatSpec.UINT24_MAX);
-        if (!hasChildrenAddress(address)) {
+        if (!BinaryDictIOUtils.hasChildrenAddress(address)) {
             return 0;
         } else if (Math.abs(address) <= FormatSpec.UINT8_MAX) {
             return 1;
@@ -802,7 +754,7 @@
      */
     private static int writeVariableSignedAddress(final byte[] buffer, int index,
             final int address) {
-        if (!hasChildrenAddress(address)) {
+        if (!BinaryDictIOUtils.hasChildrenAddress(address)) {
             buffer[index] = buffer[index + 1] = buffer[index + 2] = 0;
         } else {
             final int absAddress = Math.abs(address);
@@ -966,7 +918,7 @@
 
     private static final int writeParentAddress(final byte[] buffer, final int index,
             final int address, final FormatOptions formatOptions) {
-        if (supportsDynamicUpdate(formatOptions)) {
+        if (BinaryDictIOUtils.supportsDynamicUpdate(formatOptions)) {
             if (address == FormatSpec.NO_PARENT_ADDRESS) {
                 buffer[index] = buffer[index + 1] = buffer[index + 2] = 0;
             } else {
@@ -1315,7 +1267,7 @@
 
     static int readParentAddress(final FusionDictionaryBufferInterface buffer,
             final FormatOptions formatOptions) {
-        if (supportsDynamicUpdate(formatOptions)) {
+        if (BinaryDictIOUtils.supportsDynamicUpdate(formatOptions)) {
             final int parentAddress = buffer.readUnsignedInt24();
             final int sign = ((parentAddress & FormatSpec.MSB24) != 0) ? -1 : 1;
             return sign * (parentAddress & FormatSpec.SINT24_MAX);
@@ -1332,7 +1284,7 @@
         ++addressPointer;
 
         final int parentAddress = readParentAddress(buffer, options);
-        if (supportsDynamicUpdate(options)) {
+        if (BinaryDictIOUtils.supportsDynamicUpdate(options)) {
             addressPointer += 3;
         }
 
@@ -1459,7 +1411,7 @@
         final int originalPointer = buffer.position();
         buffer.position(address);
 
-        if (supportsDynamicUpdate(formatOptions)) {
+        if (BinaryDictIOUtils.supportsDynamicUpdate(formatOptions)) {
             result = getWordAtAddressWithParentAddress(buffer, headerSize, address, formatOptions);
         } else {
             result = getWordAtAddressWithoutParentAddress(buffer, headerSize, address,
@@ -1488,13 +1440,13 @@
             do {
                 buffer.position(currentAddress + headerSize);
                 currentInfo = readCharGroup(buffer, currentAddress, options);
-                if (isMovedGroup(currentInfo.mFlags, options)) {
+                if (BinaryDictIOUtils.isMovedGroup(currentInfo.mFlags, options)) {
                     currentAddress = currentInfo.mParentAddress + currentInfo.mOriginalAddress;
                 }
                 if (DBG && loopCounter++ > MAX_JUMPS) {
                     MakedictLog.d("Too many jumps - probably a bug");
                 }
-            } while (isMovedGroup(currentInfo.mFlags, options));
+            } while (BinaryDictIOUtils.isMovedGroup(currentInfo.mFlags, options));
             if (Integer.MIN_VALUE == frequency) frequency = currentInfo.mFrequency;
             for (int i = 0; i < currentInfo.mCharacters.length; ++i) {
                 sGetWordBuffer[index--] =
@@ -1514,7 +1466,7 @@
             final FormatOptions options) {
         buffer.position(headerSize);
         final int count = readCharGroupCount(buffer);
-        int groupOffset = getGroupCountSize(count);
+        int groupOffset = BinaryDictIOUtils.getGroupCountSize(count);
         final StringBuilder builder = new StringBuilder();
         WeightedString result = null;
 
@@ -1527,23 +1479,23 @@
                 result = new WeightedString(builder.toString(), info.mFrequency);
                 break; // and return
             }
-            if (hasChildrenAddress(info.mChildrenAddress)) {
+            if (BinaryDictIOUtils.hasChildrenAddress(info.mChildrenAddress)) {
                 if (info.mChildrenAddress > address) {
                     if (null == last) continue;
                     builder.append(new String(last.mCharacters, 0, last.mCharacters.length));
                     buffer.position(last.mChildrenAddress + headerSize);
                     i = readCharGroupCount(buffer);
-                    groupOffset = last.mChildrenAddress + getGroupCountSize(i);
+                    groupOffset = last.mChildrenAddress + BinaryDictIOUtils.getGroupCountSize(i);
                     last = null;
                     continue;
                 }
                 last = info;
             }
-            if (0 == i && hasChildrenAddress(last.mChildrenAddress)) {
+            if (0 == i && BinaryDictIOUtils.hasChildrenAddress(last.mChildrenAddress)) {
                 builder.append(new String(last.mCharacters, 0, last.mCharacters.length));
                 buffer.position(last.mChildrenAddress + headerSize);
                 i = readCharGroupCount(buffer);
-                groupOffset = last.mChildrenAddress + getGroupCountSize(i);
+                groupOffset = last.mChildrenAddress + BinaryDictIOUtils.getGroupCountSize(i);
                 last = null;
                 continue;
             }
@@ -1576,10 +1528,10 @@
         do { // Scan the linked-list node.
             final int nodeHeadPosition = buffer.position() - headerSize;
             final int count = readCharGroupCount(buffer);
-            int groupOffset = nodeHeadPosition + getGroupCountSize(count);
+            int groupOffset = nodeHeadPosition + BinaryDictIOUtils.getGroupCountSize(count);
             for (int i = count; i > 0; --i) { // Scan the array of CharGroup.
                 CharGroupInfo info = readCharGroup(buffer, groupOffset, options);
-                if (isMovedGroup(info.mFlags, options)) continue;
+                if (BinaryDictIOUtils.isMovedGroup(info.mFlags, options)) continue;
                 ArrayList<WeightedString> shortcutTargets = info.mShortcutTargets;
                 ArrayList<WeightedString> bigrams = null;
                 if (null != info.mBigrams) {
@@ -1592,7 +1544,7 @@
                         bigrams.add(new WeightedString(word.mWord, reconstructedFrequency));
                     }
                 }
-                if (hasChildrenAddress(info.mChildrenAddress)) {
+                if (BinaryDictIOUtils.hasChildrenAddress(info.mChildrenAddress)) {
                     Node children = reverseNodeMap.get(info.mChildrenAddress);
                     if (null == children) {
                         final int currentPosition = buffer.position();
diff --git a/java/src/com/android/inputmethod/latin/makedict/DynamicBinaryDictIOUtils.java b/java/src/com/android/inputmethod/latin/makedict/DynamicBinaryDictIOUtils.java
index fd728f1..5b10912 100644
--- a/java/src/com/android/inputmethod/latin/makedict/DynamicBinaryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/DynamicBinaryDictIOUtils.java
@@ -85,7 +85,7 @@
             throw new RuntimeException("this file format does not support parent addresses");
         }
         final int flags = buffer.readUnsignedByte();
-        if (BinaryDictInputOutput.isMovedGroup(flags, formatOptions)) {
+        if (BinaryDictIOUtils.isMovedGroup(flags, formatOptions)) {
             // if the group is moved, the parent address is stored in the destination group.
             // We are guaranteed to process the destination group later, so there is no need to
             // update anything here.
@@ -286,7 +286,7 @@
                 address = buffer.position();
                 final CharGroupInfo currentInfo = BinaryDictInputOutput.readCharGroup(buffer,
                         buffer.position(), header.mFormatOptions);
-                final boolean isMovedGroup = BinaryDictInputOutput.isMovedGroup(currentInfo.mFlags,
+                final boolean isMovedGroup = BinaryDictIOUtils.isMovedGroup(currentInfo.mFlags,
                         header.mFormatOptions);
                 if (isMovedGroup) continue;
                 nodeParentAddress = (currentInfo.mParentAddress == FormatSpec.NO_PARENT_ADDRESS)
diff --git a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
index a25cef5..c895a86 100644
--- a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
+++ b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
@@ -53,6 +53,7 @@
         jlong dictOffset, jlong dictSize, jboolean isUpdatable) {
     PROF_OPEN;
     PROF_START(66);
+    // TODO: Move dictionary buffer handling to policyimpl.
     const jsize sourceDirUtf8Length = env->GetStringUTFLength(sourceDir);
     if (sourceDirUtf8Length <= 0) {
         AKLOGE("DICT: Can't get sourceDir string");
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
index e50baae..7f646e3 100644
--- a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
@@ -49,9 +49,7 @@
     }
 
     AK_FORCE_INLINE bool isDynamicallyUpdatable() const {
-        // TODO: Support dynamic dictionary formats.
-        const bool isUpdatableDictionaryFormat = false;
-        return mIsUpdatable && isUpdatableDictionaryFormat;
+        return mIsUpdatable;
     }
 
  private:
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.cpp b/native/jni/src/suggest/core/dictionary/dictionary.cpp
index af00e99..2ffd494 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary.cpp
@@ -107,7 +107,7 @@
         AKLOGI("Warning: Dictionary::addUnigramWord() is called for non-updatable dictionary.");
         return;
     }
-    // TODO: Support dynamic update
+    mDictionaryStructureWithBufferPolicy->addUnigramWord(word, length, probability);
 }
 
 void Dictionary::addBigramWords(const int *const word0, const int length0, const int *const word1,
@@ -117,7 +117,8 @@
         AKLOGI("Warning: Dictionary::addBigramWords() is called for non-updatable dictionary.");
         return;
     }
-    // TODO: Support dynamic update
+    mDictionaryStructureWithBufferPolicy->addBigramWords(word0, length0, word1, length1,
+            probability);
 }
 
 void Dictionary::removeBigramWords(const int *const word0, const int length0,
@@ -127,7 +128,7 @@
         AKLOGI("Warning: Dictionary::removeBigramWords() is called for non-updatable dictionary.");
         return;
     }
-    // TODO: Support dynamic update
+    mDictionaryStructureWithBufferPolicy->removeBigramWords(word0, length0, word1, length1);
 }
 
 void Dictionary::logDictionaryInfo(JNIEnv *const env) const {
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.h b/native/jni/src/suggest/core/dictionary/dictionary.h
index 17ce479..a54b62f 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.h
+++ b/native/jni/src/suggest/core/dictionary/dictionary.h
@@ -94,9 +94,9 @@
 
     const BinaryDictionaryInfo mBinaryDictionaryInfo;
     DictionaryStructureWithBufferPolicy *const mDictionaryStructureWithBufferPolicy;
-    const BigramDictionary *mBigramDictionary;
-    SuggestInterface *mGestureSuggest;
-    SuggestInterface *mTypingSuggest;
+    const BigramDictionary *const mBigramDictionary;
+    const SuggestInterface *const mGestureSuggest;
+    const SuggestInterface *const mTypingSuggest;
 
     void logDictionaryInfo(JNIEnv *const env) const;
 };
diff --git a/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h b/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
index 37daef9..5324115 100644
--- a/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
+++ b/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
@@ -59,6 +59,18 @@
 
     virtual const DictionaryShortcutsStructurePolicy *getShortcutsStructurePolicy() const = 0;
 
+    // Returns whether the update was success or not.
+    virtual bool addUnigramWord(const int *const word, const int length,
+            const int probability) = 0;
+
+    // Returns whether the update was success or not.
+    virtual bool addBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1, const int probability) = 0;
+
+    // Returns whether the update was success or not.
+    virtual bool removeBigramWords(const int *const word0, const int length0,
+            const int *const word1, const int length1) = 0;
+
  protected:
     DictionaryStructureWithBufferPolicy() {}
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp
index cca8010..311e94d 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp
@@ -231,4 +231,22 @@
     return nodeReader.getBigramsPos();
 }
 
+bool DynamicPatriciaTriePolicy::addUnigramWord(const int *const word, const int length,
+        const int probability) {
+    // TODO: Implement.
+    return false;
+}
+
+bool DynamicPatriciaTriePolicy::addBigramWords(const int *const word0, const int length0,
+        const int *const word1, const int length1, const int probability) {
+    // TODO: Implement.
+    return false;
+}
+
+bool DynamicPatriciaTriePolicy::removeBigramWords(const int *const word0, const int length0,
+        const int *const word1, const int length1) {
+    // TODO: Implement.
+    return false;
+}
+
 } // namespace latinime
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 ad8911c..4a5192c 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
@@ -70,6 +70,14 @@
         return &mShortcutListPolicy;
     }
 
+    bool addUnigramWord(const int *const word, const int length, const int probability);
+
+    bool addBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1, const int probability);
+
+    bool removeBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1);
+
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(DynamicPatriciaTriePolicy);
     static const int MAX_CHILD_COUNT_TO_AVOID_INFINITE_LOOP;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/header/header_reading_utils.cpp b/native/jni/src/suggest/policyimpl/dictionary/header/header_reading_utils.cpp
index 23b88ec..f323876 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/header/header_reading_utils.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/header/header_reading_utils.cpp
@@ -34,7 +34,7 @@
 const HeaderReadingUtils::DictionaryFlags
         HeaderReadingUtils::NO_FLAGS = 0;
 // Flags for special processing
-// Those *must* match the flags in makedict (BinaryDictInputOutput#*_PROCESSING_FLAG) or
+// Those *must* match the flags in makedict (FormatSpec#*_PROCESSING_FLAG) or
 // something very bad (like, the apocalypse) will happen. Please update both at the same time.
 const HeaderReadingUtils::DictionaryFlags
         HeaderReadingUtils::GERMAN_UMLAUT_PROCESSING_FLAG = 0x1;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h
index 2e34480..0ed7945 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h
@@ -70,6 +70,23 @@
         return &mShortcutListPolicy;
     }
 
+    bool addUnigramWord(const int *const word, const int length, const int probability) {
+        // This dictionary format is not updatable.
+        return false;
+    }
+
+    bool addBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1, const int probability) {
+        // This dictionary format is not updatable.
+        return false;
+    }
+
+    bool removeBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1) {
+        // This dictionary format is not updatable.
+        return false;
+    }
+
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(PatriciaTriePolicy);