diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderUtils.java
index 25e1bcd..b534bcb 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderUtils.java
@@ -17,7 +17,6 @@
 package com.android.inputmethod.latin.makedict;
 
 import com.android.inputmethod.annotations.UsedForTesting;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 
 import java.io.File;
 import java.io.IOException;
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java
index 1593dea..39bd98b 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictEncoderUtils.java
@@ -22,7 +22,6 @@
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNode;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
index caf3cf3..a180f1c 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
@@ -18,13 +18,7 @@
 
 import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.Constants;
-import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils.DictBuffer;
-import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
-import com.android.inputmethod.latin.utils.ByteArrayDictBuffer;
 
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.ArrayList;
diff --git a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
index 8f73b27..e2be907 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
@@ -67,46 +67,6 @@
     }
 
     /**
-     * A string with a probability.
-     *
-     * This represents an "attribute", that is either a bigram or a shortcut.
-     */
-    public static final class WeightedString {
-        public final String mWord;
-        public ProbabilityInfo mProbabilityInfo;
-
-        public WeightedString(final String word, final int probability) {
-            this(word, new ProbabilityInfo(probability));
-        }
-
-        public WeightedString(final String word, final ProbabilityInfo probabilityInfo) {
-            mWord = word;
-            mProbabilityInfo = probabilityInfo;
-        }
-
-        public int getProbability() {
-            return mProbabilityInfo.mProbability;
-        }
-
-        public void setProbability(final int probability) {
-            mProbabilityInfo = new ProbabilityInfo(probability);
-        }
-
-        @Override
-        public int hashCode() {
-            return Arrays.hashCode(new Object[] { mWord, mProbabilityInfo});
-        }
-
-        @Override
-        public boolean equals(Object o) {
-            if (o == this) return true;
-            if (!(o instanceof WeightedString)) return false;
-            final WeightedString w = (WeightedString)o;
-            return mWord.equals(w.mWord) && mProbabilityInfo.equals(w.mProbabilityInfo);
-        }
-    }
-
-    /**
      * PtNode is a group of characters, with probability information, shortcut targets, bigrams,
      * and children (Pt means Patricia Trie).
      *
diff --git a/java/src/com/android/inputmethod/latin/makedict/PtNodeInfo.java b/java/src/com/android/inputmethod/latin/makedict/PtNodeInfo.java
index f52117c..862e8c1 100644
--- a/java/src/com/android/inputmethod/latin/makedict/PtNodeInfo.java
+++ b/java/src/com/android/inputmethod/latin/makedict/PtNodeInfo.java
@@ -16,15 +16,12 @@
 
 package com.android.inputmethod.latin.makedict;
 
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
-
 import java.util.ArrayList;
 
 /**
  * Raw PtNode info straight out of a file. This will contain numbers for addresses.
  */
 public final class PtNodeInfo {
-
     public final int mOriginalAddress;
     public final int mEndAddress;
     public final int mFlags;
diff --git a/java/src/com/android/inputmethod/latin/makedict/Ver2DictDecoder.java b/java/src/com/android/inputmethod/latin/makedict/Ver2DictDecoder.java
index ab24fbc..7091c11 100644
--- a/java/src/com/android/inputmethod/latin/makedict/Ver2DictDecoder.java
+++ b/java/src/com/android/inputmethod/latin/makedict/Ver2DictDecoder.java
@@ -20,7 +20,6 @@
 import com.android.inputmethod.latin.BinaryDictionary;
 import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils.CharEncoding;
 import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils.DictBuffer;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.utils.CollectionUtils;
 
 import java.io.File;
diff --git a/java/src/com/android/inputmethod/latin/makedict/Ver2DictEncoder.java b/java/src/com/android/inputmethod/latin/makedict/Ver2DictEncoder.java
index e247f01..a286190 100644
--- a/java/src/com/android/inputmethod/latin/makedict/Ver2DictEncoder.java
+++ b/java/src/com/android/inputmethod/latin/makedict/Ver2DictEncoder.java
@@ -21,7 +21,6 @@
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNode;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 
 import java.io.File;
 import java.io.FileNotFoundException;
diff --git a/java/src/com/android/inputmethod/latin/makedict/Ver4DictDecoder.java b/java/src/com/android/inputmethod/latin/makedict/Ver4DictDecoder.java
index afe8231..f3fad7e 100644
--- a/java/src/com/android/inputmethod/latin/makedict/Ver4DictDecoder.java
+++ b/java/src/com/android/inputmethod/latin/makedict/Ver4DictDecoder.java
@@ -18,7 +18,6 @@
 
 import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.BinaryDictionary;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.utils.CollectionUtils;
 import com.android.inputmethod.latin.utils.FileUtils;
 
diff --git a/java/src/com/android/inputmethod/latin/makedict/Ver4DictEncoder.java b/java/src/com/android/inputmethod/latin/makedict/Ver4DictEncoder.java
index a50bad9..dab9a43 100644
--- a/java/src/com/android/inputmethod/latin/makedict/Ver4DictEncoder.java
+++ b/java/src/com/android/inputmethod/latin/makedict/Ver4DictEncoder.java
@@ -21,7 +21,6 @@
 import com.android.inputmethod.latin.Dictionary;
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNode;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.utils.BinaryDictionaryUtils;
 import com.android.inputmethod.latin.utils.LocaleUtils;
 
diff --git a/java/src/com/android/inputmethod/latin/makedict/WeightedString.java b/java/src/com/android/inputmethod/latin/makedict/WeightedString.java
new file mode 100644
index 0000000..f6782df
--- /dev/null
+++ b/java/src/com/android/inputmethod/latin/makedict/WeightedString.java
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2014 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.annotations.UsedForTesting;
+
+import java.util.Arrays;
+
+/**
+ * A string with a probability.
+ *
+ * This represents an "attribute", that is either a bigram or a shortcut.
+ */
+public final class WeightedString {
+    public final String mWord;
+    public ProbabilityInfo mProbabilityInfo;
+
+    public WeightedString(final String word, final int probability) {
+        this(word, new ProbabilityInfo(probability));
+    }
+
+    public WeightedString(final String word, final ProbabilityInfo probabilityInfo) {
+        mWord = word;
+        mProbabilityInfo = probabilityInfo;
+    }
+
+    @UsedForTesting
+    public int getProbability() {
+        return mProbabilityInfo.mProbability;
+    }
+
+    public void setProbability(final int probability) {
+        mProbabilityInfo = new ProbabilityInfo(probability);
+    }
+
+    @Override
+    public int hashCode() {
+        return Arrays.hashCode(new Object[] { mWord, mProbabilityInfo});
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == this) return true;
+        if (!(o instanceof WeightedString)) return false;
+        final WeightedString w = (WeightedString)o;
+        return mWord.equals(w.mWord) && mProbabilityInfo.equals(w.mProbabilityInfo);
+    }
+}
\ No newline at end of file
diff --git a/java/src/com/android/inputmethod/latin/makedict/WordProperty.java b/java/src/com/android/inputmethod/latin/makedict/WordProperty.java
index 1fc61e1..d94cec4 100644
--- a/java/src/com/android/inputmethod/latin/makedict/WordProperty.java
+++ b/java/src/com/android/inputmethod/latin/makedict/WordProperty.java
@@ -18,7 +18,6 @@
 
 import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.BinaryDictionary;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.utils.CollectionUtils;
 import com.android.inputmethod.latin.utils.CombinedFormatUtils;
 import com.android.inputmethod.latin.utils.StringUtils;
diff --git a/java/src/com/android/inputmethod/latin/utils/CombinedFormatUtils.java b/java/src/com/android/inputmethod/latin/utils/CombinedFormatUtils.java
index bb7ae2f..c660075 100644
--- a/java/src/com/android/inputmethod/latin/utils/CombinedFormatUtils.java
+++ b/java/src/com/android/inputmethod/latin/utils/CombinedFormatUtils.java
@@ -18,8 +18,8 @@
 
 import com.android.inputmethod.latin.makedict.DictionaryHeader;
 import com.android.inputmethod.latin.makedict.ProbabilityInfo;
+import com.android.inputmethod.latin.makedict.WeightedString;
 import com.android.inputmethod.latin.makedict.WordProperty;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 
 import java.util.HashMap;
 
diff --git a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
index 31a4849..5b97283 100644
--- a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
+++ b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
@@ -46,15 +46,16 @@
     char sourceDirChars[sourceDirUtf8Length + 1];
     env->GetStringUTFRegion(sourceDir, 0, env->GetStringLength(sourceDir), sourceDirChars);
     sourceDirChars[sourceDirUtf8Length] = '\0';
-    DictionaryStructureWithBufferPolicy::StructurePolicyPtr dictionaryStructureWithBufferPolicy =
+    DictionaryStructureWithBufferPolicy::StructurePolicyPtr dictionaryStructureWithBufferPolicy(
             DictionaryStructureWithBufferPolicyFactory::newDictionaryStructureWithBufferPolicy(
                     sourceDirChars, static_cast<int>(dictOffset), static_cast<int>(dictSize),
-                    isUpdatable == JNI_TRUE);
-    if (!dictionaryStructureWithBufferPolicy.get()) {
+                    isUpdatable == JNI_TRUE));
+    if (!dictionaryStructureWithBufferPolicy) {
         return 0;
     }
 
-    Dictionary *const dictionary = new Dictionary(env, dictionaryStructureWithBufferPolicy);
+    Dictionary *const dictionary =
+            new Dictionary(env, std::move(dictionaryStructureWithBufferPolicy));
     PROF_END(66);
     PROF_CLOSE;
     return reinterpret_cast<jlong>(dictionary);
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.cpp b/native/jni/src/suggest/core/dictionary/dictionary.cpp
index 035232f..59a8a55 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary.cpp
@@ -34,9 +34,9 @@
 
 const int Dictionary::HEADER_ATTRIBUTE_BUFFER_SIZE = 32;
 
-Dictionary::Dictionary(JNIEnv *env, const DictionaryStructureWithBufferPolicy::StructurePolicyPtr
-        &dictionaryStructureWithBufferPolicy)
-        : mDictionaryStructureWithBufferPolicy(dictionaryStructureWithBufferPolicy),
+Dictionary::Dictionary(JNIEnv *env, DictionaryStructureWithBufferPolicy::StructurePolicyPtr
+        dictionaryStructureWithBufferPolicy)
+        : mDictionaryStructureWithBufferPolicy(std::move(dictionaryStructureWithBufferPolicy)),
           mBigramDictionary(new BigramDictionary(mDictionaryStructureWithBufferPolicy.get())),
           mGestureSuggest(new Suggest(GestureSuggestPolicyFactory::getGestureSuggestPolicy())),
           mTypingSuggest(new Suggest(TypingSuggestPolicyFactory::getTypingSuggestPolicy())) {
@@ -53,7 +53,7 @@
     if (suggestOptions->isGesture()) {
         DicTraverseSession::initSessionInstance(
                 traverseSession, this, prevWordCodePoints, prevWordLength, suggestOptions);
-        result = mGestureSuggest.get()->getSuggestions(proximityInfo, traverseSession, xcoordinates,
+        result = mGestureSuggest->getSuggestions(proximityInfo, traverseSession, xcoordinates,
                 ycoordinates, times, pointerIds, inputCodePoints, inputSize, commitPoint, outWords,
                 outputScores, spaceIndices, outputTypes, outputAutoCommitFirstWordConfidence);
         if (DEBUG_DICT) {
@@ -63,7 +63,7 @@
     } else {
         DicTraverseSession::initSessionInstance(
                 traverseSession, this, prevWordCodePoints, prevWordLength, suggestOptions);
-        result = mTypingSuggest.get()->getSuggestions(proximityInfo, traverseSession, xcoordinates,
+        result = mTypingSuggest->getSuggestions(proximityInfo, traverseSession, xcoordinates,
                 ycoordinates, times, pointerIds, inputCodePoints, inputSize, commitPoint,
                 outWords, outputScores, spaceIndices, outputTypes,
                 outputAutoCommitFirstWordConfidence);
@@ -78,7 +78,7 @@
         int *outputTypes) const {
     TimeKeeper::setCurrentTime();
     if (length <= 0) return 0;
-    return mBigramDictionary.get()->getPredictions(word, length, outWords, outputScores,
+    return mBigramDictionary->getPredictions(word, length, outWords, outputScores,
             outputTypes);
 }
 
@@ -95,7 +95,7 @@
 int Dictionary::getBigramProbability(const int *word0, int length0, const int *word1,
         int length1) const {
     TimeKeeper::setCurrentTime();
-    return mBigramDictionary.get()->getBigramProbability(word0, length0, word1, length1);
+    return mBigramDictionary->getBigramProbability(word0, length0, word1, length1);
 }
 
 void Dictionary::addUnigramWord(const int *const word, const int length, const int probability,
@@ -103,7 +103,7 @@
         const int shortcutProbability, const bool isNotAWord, const bool isBlacklisted,
         const int timestamp) {
     TimeKeeper::setCurrentTime();
-    mDictionaryStructureWithBufferPolicy.get()->addUnigramWord(word, length, probability,
+    mDictionaryStructureWithBufferPolicy->addUnigramWord(word, length, probability,
             shortcutTargetCodePoints, shortcutLength, shortcutProbability, isNotAWord,
             isBlacklisted, timestamp);
 }
@@ -111,48 +111,48 @@
 void Dictionary::addBigramWords(const int *const word0, const int length0, const int *const word1,
         const int length1, const int probability, const int timestamp) {
     TimeKeeper::setCurrentTime();
-    mDictionaryStructureWithBufferPolicy.get()->addBigramWords(word0, length0, word1, length1,
+    mDictionaryStructureWithBufferPolicy->addBigramWords(word0, length0, word1, length1,
             probability, timestamp);
 }
 
 void Dictionary::removeBigramWords(const int *const word0, const int length0,
         const int *const word1, const int length1) {
     TimeKeeper::setCurrentTime();
-    mDictionaryStructureWithBufferPolicy.get()->removeBigramWords(word0, length0, word1, length1);
+    mDictionaryStructureWithBufferPolicy->removeBigramWords(word0, length0, word1, length1);
 }
 
 void Dictionary::flush(const char *const filePath) {
     TimeKeeper::setCurrentTime();
-    mDictionaryStructureWithBufferPolicy.get()->flush(filePath);
+    mDictionaryStructureWithBufferPolicy->flush(filePath);
 }
 
 void Dictionary::flushWithGC(const char *const filePath) {
     TimeKeeper::setCurrentTime();
-    mDictionaryStructureWithBufferPolicy.get()->flushWithGC(filePath);
+    mDictionaryStructureWithBufferPolicy->flushWithGC(filePath);
 }
 
 bool Dictionary::needsToRunGC(const bool mindsBlockByGC) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy.get()->needsToRunGC(mindsBlockByGC);
+    return mDictionaryStructureWithBufferPolicy->needsToRunGC(mindsBlockByGC);
 }
 
 void Dictionary::getProperty(const char *const query, const int queryLength, char *const outResult,
         const int maxResultLength) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy.get()->getProperty(query, queryLength, outResult,
+    return mDictionaryStructureWithBufferPolicy->getProperty(query, queryLength, outResult,
             maxResultLength);
 }
 
 const WordProperty Dictionary::getWordProperty(const int *const codePoints,
         const int codePointCount) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy.get()->getWordProperty(
+    return mDictionaryStructureWithBufferPolicy->getWordProperty(
             codePoints, codePointCount);
 }
 
 int Dictionary::getNextWordAndNextToken(const int token, int *const outCodePoints) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy.get()->getNextWordAndNextToken(
+    return mDictionaryStructureWithBufferPolicy->getNextWordAndNextToken(
             token, outCodePoints);
 }
 
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.h b/native/jni/src/suggest/core/dictionary/dictionary.h
index c58be84..a7f19c9 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.h
+++ b/native/jni/src/suggest/core/dictionary/dictionary.h
@@ -18,6 +18,7 @@
 #define LATINIME_DICTIONARY_H
 
 #include <stdint.h>
+#include <memory>
 
 #include "defines.h"
 #include "jni.h"
@@ -26,7 +27,6 @@
 #include "suggest/core/policy/dictionary_header_structure_policy.h"
 #include "suggest/core/policy/dictionary_structure_with_buffer_policy.h"
 #include "suggest/core/suggest_interface.h"
-#include "utils/exclusive_ownership_pointer.h"
 
 namespace latinime {
 
@@ -58,8 +58,8 @@
     static const int KIND_FLAG_POSSIBLY_OFFENSIVE = 0x80000000;
     static const int KIND_FLAG_EXACT_MATCH = 0x40000000;
 
-    Dictionary(JNIEnv *env, const DictionaryStructureWithBufferPolicy::StructurePolicyPtr
-            &dictionaryStructureWithBufferPolicy);
+    Dictionary(JNIEnv *env, DictionaryStructureWithBufferPolicy::StructurePolicyPtr
+            dictionaryStructureWithBufferPolicy);
 
     int getSuggestions(ProximityInfo *proximityInfo, DicTraverseSession *traverseSession,
             int *xcoordinates, int *ycoordinates, int *times, int *pointerIds, int *inputCodePoints,
@@ -108,8 +108,8 @@
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(Dictionary);
 
-    typedef ExclusiveOwnershipPointer<BigramDictionary> BigramDictionaryPtr;
-    typedef ExclusiveOwnershipPointer<SuggestInterface> SuggestInterfacePtr;
+    typedef std::unique_ptr<BigramDictionary> BigramDictionaryPtr;
+    typedef std::unique_ptr<SuggestInterface> SuggestInterfacePtr;
 
     static const int HEADER_ATTRIBUTE_BUFFER_SIZE;
 
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 38e8ff1..b6dc7d0 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
@@ -17,9 +17,10 @@
 #ifndef LATINIME_DICTIONARY_STRUCTURE_POLICY_H
 #define LATINIME_DICTIONARY_STRUCTURE_POLICY_H
 
+#include <memory>
+
 #include "defines.h"
 #include "suggest/core/dictionary/word_property.h"
-#include "utils/exclusive_ownership_pointer.h"
 
 namespace latinime {
 
@@ -35,7 +36,7 @@
  */
 class DictionaryStructureWithBufferPolicy {
  public:
-    typedef ExclusiveOwnershipPointer<DictionaryStructureWithBufferPolicy> StructurePolicyPtr;
+    typedef std::unique_ptr<DictionaryStructureWithBufferPolicy> StructurePolicyPtr;
 
     virtual ~DictionaryStructureWithBufferPolicy() {}
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.cpp
index 04f1198..79bcf6f 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.cpp
@@ -41,7 +41,7 @@
         if (isUpdatable) {
             AKLOGE("One file dictionaries don't support updating. path: %s", path);
             ASSERT(false);
-            return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+            return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
         }
         return newPolicyforFileDict(path, bufOffset, size);
     }
@@ -55,13 +55,13 @@
     getHeaderFilePathInDictDir(path, headerFilePathBufSize, headerFilePath);
     // Allocated buffer in MmapedBuffer::openBuffer() will be freed in the destructor of
     // MmappedBufferPtr if the instance has the responsibility.
-    MmappedBuffer::MmappedBufferPtr mmappedBuffer = MmappedBuffer::openBuffer(headerFilePath,
-            isUpdatable);
-    if (!mmappedBuffer.get()) {
-        return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+    MmappedBuffer::MmappedBufferPtr mmappedBuffer(
+            MmappedBuffer::openBuffer(headerFilePath, isUpdatable));
+    if (!mmappedBuffer) {
+        return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
     }
-    switch (FormatUtils::detectFormatVersion(mmappedBuffer.get()->getBuffer(),
-            mmappedBuffer.get()->getBufferSize())) {
+    switch (FormatUtils::detectFormatVersion(mmappedBuffer->getBuffer(),
+            mmappedBuffer->getBufferSize())) {
         case FormatUtils::VERSION_2:
             AKLOGE("Given path is a directory but the format is version 2. path: %s", path);
             break;
@@ -72,25 +72,25 @@
                     Ver4DictConstants::HEADER_FILE_EXTENSION, dictDirPathBufSize, dictPath)) {
                 AKLOGE("Dictionary file name is not valid as a ver4 dictionary. path: %s", path);
                 ASSERT(false);
-                return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+                return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
             }
-            const Ver4DictBuffers::Ver4DictBuffersPtr dictBuffers =
-                    Ver4DictBuffers::openVer4DictBuffers(dictPath, mmappedBuffer);
-            if (!dictBuffers.get() || !dictBuffers.get()->isValid()) {
+            Ver4DictBuffers::Ver4DictBuffersPtr dictBuffers(
+                    Ver4DictBuffers::openVer4DictBuffers(dictPath, std::move(mmappedBuffer)));
+            if (!dictBuffers || !dictBuffers->isValid()) {
                 AKLOGE("DICT: The dictionary doesn't satisfy ver4 format requirements. path: %s",
                         path);
                 ASSERT(false);
-                return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+                return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
             }
             return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(
-                    new Ver4PatriciaTriePolicy(dictBuffers));
+                    new Ver4PatriciaTriePolicy(std::move(dictBuffers)));
         }
         default:
             AKLOGE("DICT: dictionary format is unknown, bad magic number. path: %s", path);
             break;
     }
     ASSERT(false);
-    return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+    return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
 }
 
 /* static */ DictionaryStructureWithBufferPolicy::StructurePolicyPtr
@@ -98,16 +98,16 @@
                 const char *const path, const int bufOffset, const int size) {
     // Allocated buffer in MmapedBuffer::openBuffer() will be freed in the destructor of
     // MmappedBufferPtr if the instance has the responsibility.
-    MmappedBuffer::MmappedBufferPtr mmappedBuffer = MmappedBuffer::openBuffer(path, bufOffset,
-            size, false /* isUpdatable */);
-    if (!mmappedBuffer.get()) {
-        return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+    MmappedBuffer::MmappedBufferPtr mmappedBuffer(
+            MmappedBuffer::openBuffer(path, bufOffset, size, false /* isUpdatable */));
+    if (!mmappedBuffer) {
+        return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
     }
-    switch (FormatUtils::detectFormatVersion(mmappedBuffer.get()->getBuffer(),
-            mmappedBuffer.get()->getBufferSize())) {
+    switch (FormatUtils::detectFormatVersion(mmappedBuffer->getBuffer(),
+            mmappedBuffer->getBufferSize())) {
         case FormatUtils::VERSION_2:
             return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(
-                    new PatriciaTriePolicy(mmappedBuffer));
+                    new PatriciaTriePolicy(std::move(mmappedBuffer)));
         case FormatUtils::VERSION_4:
             AKLOGE("Given path is a file but the format is version 4. path: %s", path);
             break;
@@ -116,7 +116,7 @@
             break;
     }
     ASSERT(false);
-    return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(0);
+    return DictionaryStructureWithBufferPolicy::StructurePolicyPtr(nullptr);
 }
 
 /* static */ void DictionaryStructureWithBufferPolicyFactory::getHeaderFilePathInDictDir(
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.h b/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.h
index 45ab529..9454ddf 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/dictionary_structure_with_buffer_policy_factory.h
@@ -21,7 +21,6 @@
 
 #include "defines.h"
 #include "suggest/core/policy/dictionary_structure_with_buffer_policy.h"
-#include "utils/exclusive_ownership_pointer.h"
 
 namespace latinime {
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h
index 6a2345a..11a40de 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h
@@ -37,12 +37,11 @@
 
 class PatriciaTriePolicy : public DictionaryStructureWithBufferPolicy {
  public:
-    PatriciaTriePolicy(const MmappedBuffer::MmappedBufferPtr &mmappedBuffer)
-            : mMmappedBuffer(mmappedBuffer),
-              mHeaderPolicy(mMmappedBuffer.get()->getBuffer(), FormatUtils::VERSION_2),
-              mDictRoot(mMmappedBuffer.get()->getBuffer() + mHeaderPolicy.getSize()),
-              mDictBufferSize(mMmappedBuffer.get()->getBufferSize()
-                      - mHeaderPolicy.getSize()),
+    PatriciaTriePolicy(MmappedBuffer::MmappedBufferPtr mmappedBuffer)
+            : mMmappedBuffer(std::move(mmappedBuffer)),
+              mHeaderPolicy(mMmappedBuffer->getBuffer(), FormatUtils::VERSION_2),
+              mDictRoot(mMmappedBuffer->getBuffer() + mHeaderPolicy.getSize()),
+              mDictBufferSize(mMmappedBuffer->getBufferSize() - mHeaderPolicy.getSize()),
               mBigramListPolicy(mDictRoot), mShortcutListPolicy(mDictRoot),
               mPtNodeReader(mDictRoot, mDictBufferSize, &mBigramListPolicy, &mShortcutListPolicy),
               mPtNodeArrayReader(mDictRoot, mDictBufferSize),
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/single_dict_content.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/single_dict_content.h
index edf6583..2156422 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/single_dict_content.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/single_dict_content.h
@@ -31,15 +31,14 @@
     SingleDictContent(const char *const dictPath, const char *const contentFileName,
             const bool isUpdatable)
             : mMmappedBuffer(MmappedBuffer::openBuffer(dictPath, contentFileName, isUpdatable)),
-              mExpandableContentBuffer(mMmappedBuffer.get() ?
-                              mMmappedBuffer.get()->getBuffer() : nullptr,
-                      mMmappedBuffer.get() ? mMmappedBuffer.get()->getBufferSize() : 0,
+              mExpandableContentBuffer(mMmappedBuffer ? mMmappedBuffer->getBuffer() : nullptr,
+                      mMmappedBuffer ? mMmappedBuffer->getBufferSize() : 0,
                       BufferWithExtendableBuffer::DEFAULT_MAX_ADDITIONAL_BUFFER_SIZE),
-              mIsValid(mMmappedBuffer.get()) {}
+              mIsValid(mMmappedBuffer) {}
 
     SingleDictContent()
-            : mMmappedBuffer(0), mExpandableContentBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE),
-              mIsValid(true) {}
+            : mMmappedBuffer(nullptr),
+              mExpandableContentBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE), mIsValid(true) {}
 
     virtual ~SingleDictContent() {}
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/sparse_table_dict_content.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/sparse_table_dict_content.h
index 2bb7f9a..fb6c88e 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/sparse_table_dict_content.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/content/sparse_table_dict_content.h
@@ -38,26 +38,25 @@
                       MmappedBuffer::openBuffer(dictPath, lookupTableFileName, isUpdatable)),
               mAddressTableBuffer(
                       MmappedBuffer::openBuffer(dictPath, addressTableFileName, isUpdatable)),
-              mContentBuffer(MmappedBuffer::openBuffer(dictPath, contentFileName, isUpdatable)),
+              mContentBuffer(
+                      MmappedBuffer::openBuffer(dictPath, contentFileName, isUpdatable)),
               mExpandableLookupTableBuffer(
-                      mLookupTableBuffer.get() ? mLookupTableBuffer.get()->getBuffer() : nullptr,
-                      mLookupTableBuffer.get() ? mLookupTableBuffer.get()->getBufferSize() : 0,
+                      mLookupTableBuffer ? mLookupTableBuffer->getBuffer() : nullptr,
+                      mLookupTableBuffer ? mLookupTableBuffer->getBufferSize() : 0,
                       BufferWithExtendableBuffer::DEFAULT_MAX_ADDITIONAL_BUFFER_SIZE),
               mExpandableAddressTableBuffer(
-                      mAddressTableBuffer.get() ? mAddressTableBuffer.get()->getBuffer() : nullptr,
-                      mAddressTableBuffer.get() ? mAddressTableBuffer.get()->getBufferSize() : 0,
+                      mAddressTableBuffer ? mAddressTableBuffer->getBuffer() : nullptr,
+                      mAddressTableBuffer ? mAddressTableBuffer->getBufferSize() : 0,
                       BufferWithExtendableBuffer::DEFAULT_MAX_ADDITIONAL_BUFFER_SIZE),
-              mExpandableContentBuffer(mContentBuffer.get() ?
-                              mContentBuffer.get()->getBuffer() : nullptr,
-                      mContentBuffer.get() ? mContentBuffer.get()->getBufferSize() : 0,
+              mExpandableContentBuffer(mContentBuffer ? mContentBuffer->getBuffer() : nullptr,
+                      mContentBuffer ? mContentBuffer->getBufferSize() : 0,
                       BufferWithExtendableBuffer::DEFAULT_MAX_ADDITIONAL_BUFFER_SIZE),
               mAddressLookupTable(&mExpandableLookupTableBuffer, &mExpandableAddressTableBuffer,
                       sparseTableBlockSize, sparseTableDataSize),
-              mIsValid(mLookupTableBuffer.get() && mAddressTableBuffer.get()
-                      && mContentBuffer.get()) {}
+              mIsValid(mLookupTableBuffer && mAddressTableBuffer && mContentBuffer) {}
 
     SparseTableDictContent(const int sparseTableBlockSize, const int sparseTableDataSize)
-            : mLookupTableBuffer(0), mAddressTableBuffer(0), mContentBuffer(0),
+            : mLookupTableBuffer(), mAddressTableBuffer(), mContentBuffer(),
               mExpandableLookupTableBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE),
               mExpandableAddressTableBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE),
               mExpandableContentBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE),
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.cpp
index 5ee4b79..9319ea9 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.cpp
@@ -27,15 +27,15 @@
 namespace latinime {
 
 /* static */ Ver4DictBuffers::Ver4DictBuffersPtr Ver4DictBuffers::openVer4DictBuffers(
-        const char *const dictPath, const MmappedBuffer::MmappedBufferPtr &headerBuffer) {
-    if (!headerBuffer.get()) {
+        const char *const dictPath, MmappedBuffer::MmappedBufferPtr headerBuffer) {
+    if (!headerBuffer) {
         ASSERT(false);
         AKLOGE("The header buffer must be valid to open ver4 dict buffers.");
         return Ver4DictBuffersPtr(nullptr);
     }
     // TODO: take only dictDirPath, and open both header and trie files in the constructor below
-    return Ver4DictBuffersPtr(new Ver4DictBuffers(
-            dictPath, headerBuffer, headerBuffer.get()->isUpdatable()));
+    const bool isUpdatable = headerBuffer->isUpdatable();
+    return Ver4DictBuffersPtr(new Ver4DictBuffers(dictPath, std::move(headerBuffer), isUpdatable));
 }
 
 bool Ver4DictBuffers::flushHeaderAndDictBuffers(const char *const dictDirPath,
@@ -113,27 +113,25 @@
 }
 
 Ver4DictBuffers::Ver4DictBuffers(const char *const dictPath,
-        const MmappedBuffer::MmappedBufferPtr &headerBuffer, const bool isUpdatable)
-        : mHeaderBuffer(headerBuffer),
+        MmappedBuffer::MmappedBufferPtr headerBuffer, const bool isUpdatable)
+        : mHeaderBuffer(std::move(headerBuffer)),
           mDictBuffer(MmappedBuffer::openBuffer(dictPath,
                   Ver4DictConstants::TRIE_FILE_EXTENSION, isUpdatable)),
-          mHeaderPolicy(headerBuffer.get()->getBuffer(), FormatUtils::VERSION_4),
-          mExpandableHeaderBuffer(headerBuffer.get() ? headerBuffer.get()->getBuffer() : nullptr,
+          mHeaderPolicy(mHeaderBuffer->getBuffer(), FormatUtils::VERSION_4),
+          mExpandableHeaderBuffer(mHeaderBuffer ? mHeaderBuffer->getBuffer() : nullptr,
                   mHeaderPolicy.getSize(),
                   BufferWithExtendableBuffer::DEFAULT_MAX_ADDITIONAL_BUFFER_SIZE),
-          mExpandableTrieBuffer(mDictBuffer.get() ? mDictBuffer.get()->getBuffer() : nullptr,
-                  mDictBuffer.get() ? mDictBuffer.get()->getBufferSize() : 0,
+          mExpandableTrieBuffer(mDictBuffer ? mDictBuffer->getBuffer() : nullptr,
+                  mDictBuffer ? mDictBuffer->getBufferSize() : 0,
                   BufferWithExtendableBuffer::DEFAULT_MAX_ADDITIONAL_BUFFER_SIZE),
           mTerminalPositionLookupTable(dictPath, isUpdatable),
-          mProbabilityDictContent(dictPath, mHeaderPolicy.hasHistoricalInfoOfWords(),
-                  isUpdatable),
-          mBigramDictContent(dictPath, mHeaderPolicy.hasHistoricalInfoOfWords(),
-                  isUpdatable),
+          mProbabilityDictContent(dictPath, mHeaderPolicy.hasHistoricalInfoOfWords(), isUpdatable),
+          mBigramDictContent(dictPath, mHeaderPolicy.hasHistoricalInfoOfWords(), isUpdatable),
           mShortcutDictContent(dictPath, isUpdatable),
           mIsUpdatable(isUpdatable) {}
 
 Ver4DictBuffers::Ver4DictBuffers(const HeaderPolicy *const headerPolicy)
-        : mHeaderBuffer(0), mDictBuffer(0), mHeaderPolicy(),
+        : mHeaderBuffer(nullptr), mDictBuffer(nullptr), mHeaderPolicy(),
           mExpandableHeaderBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE),
           mExpandableTrieBuffer(Ver4DictConstants::MAX_DICTIONARY_SIZE),
           mTerminalPositionLookupTable(),
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.h
index 776bb98..ab756bb 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_dict_buffers.h
@@ -17,6 +17,8 @@
 #ifndef LATINIME_VER4_DICT_BUFFER_H
 #define LATINIME_VER4_DICT_BUFFER_H
 
+#include <memory>
+
 #include "defines.h"
 #include "suggest/policyimpl/dictionary/header/header_policy.h"
 #include "suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.h"
@@ -31,10 +33,10 @@
 
 class Ver4DictBuffers {
  public:
-    typedef ExclusiveOwnershipPointer<Ver4DictBuffers> Ver4DictBuffersPtr;
+    typedef std::unique_ptr<Ver4DictBuffers> Ver4DictBuffersPtr;
 
     static Ver4DictBuffersPtr openVer4DictBuffers(const char *const dictDirPath,
-            const MmappedBuffer::MmappedBufferPtr &headerBuffer);
+            MmappedBuffer::MmappedBufferPtr headerBuffer);
 
     static AK_FORCE_INLINE Ver4DictBuffersPtr createVer4DictBuffers(
             const HeaderPolicy *const headerPolicy) {
@@ -42,7 +44,7 @@
     }
 
     AK_FORCE_INLINE bool isValid() const {
-        return mHeaderBuffer.get() && mDictBuffer.get() && mHeaderPolicy.isValid()
+        return mHeaderBuffer && mDictBuffer && mHeaderPolicy.isValid()
                 && mProbabilityDictContent.isValid() && mTerminalPositionLookupTable.isValid()
                 && mBigramDictContent.isValid() && mShortcutDictContent.isValid();
     }
@@ -118,7 +120,7 @@
     DISALLOW_COPY_AND_ASSIGN(Ver4DictBuffers);
 
     Ver4DictBuffers(const char *const dictDirPath,
-            const MmappedBuffer::MmappedBufferPtr &headerBuffer, const bool isUpdatable);
+            const MmappedBuffer::MmappedBufferPtr headerBuffer, const bool isUpdatable);
 
     Ver4DictBuffers(const HeaderPolicy *const headerPolicy);
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp
index 4d1b0da..1a38a27 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp
@@ -135,7 +135,7 @@
     if (ptNodeParams.isDeleted()) {
         return NOT_A_DICT_POS;
     }
-    return mBuffers.get()->getShortcutDictContent()->getShortcutListHeadPos(
+    return mBuffers->getShortcutDictContent()->getShortcutListHeadPos(
             ptNodeParams.getTerminalId());
 }
 
@@ -147,7 +147,7 @@
     if (ptNodeParams.isDeleted()) {
         return NOT_A_DICT_POS;
     }
-    return mBuffers.get()->getBigramDictContent()->getBigramListHeadPos(
+    return mBuffers->getBigramDictContent()->getBigramListHeadPos(
             ptNodeParams.getTerminalId());
 }
 
@@ -155,7 +155,7 @@
         const int probability, const int *const shortcutTargetCodePoints, const int shortcutLength,
         const int shortcutProbability, const bool isNotAWord, const bool isBlacklisted,
         const int timestamp) {
-    if (!mBuffers.get()->isUpdatable()) {
+    if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: addUnigramWord() is called for non-updatable dictionary.");
         return false;
     }
@@ -205,7 +205,7 @@
 bool Ver4PatriciaTriePolicy::addBigramWords(const int *const word0, const int length0,
         const int *const word1, const int length1, const int probability,
         const int timestamp) {
-    if (!mBuffers.get()->isUpdatable()) {
+    if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: addBigramWords() is called for non-updatable dictionary.");
         return false;
     }
@@ -243,7 +243,7 @@
 
 bool Ver4PatriciaTriePolicy::removeBigramWords(const int *const word0, const int length0,
         const int *const word1, const int length1) {
-    if (!mBuffers.get()->isUpdatable()) {
+    if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: addBigramWords() is called for non-updatable dictionary.");
         return false;
     }
@@ -276,7 +276,7 @@
 }
 
 void Ver4PatriciaTriePolicy::flush(const char *const filePath) {
-    if (!mBuffers.get()->isUpdatable()) {
+    if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: flush() is called for non-updatable dictionary. filePath: %s", filePath);
         return;
     }
@@ -287,7 +287,7 @@
 }
 
 void Ver4PatriciaTriePolicy::flushWithGC(const char *const filePath) {
-    if (!mBuffers.get()->isUpdatable()) {
+    if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: flushWithGC() is called for non-updatable dictionary.");
         return;
     }
@@ -298,11 +298,11 @@
 }
 
 bool Ver4PatriciaTriePolicy::needsToRunGC(const bool mindsBlockByGC) const {
-    if (!mBuffers.get()->isUpdatable()) {
+    if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: needsToRunGC() is called for non-updatable dictionary.");
         return false;
     }
-    if (mBuffers.get()->isNearSizeLimit()) {
+    if (mBuffers->isNearSizeLimit()) {
         // Additional buffer size is near the limit.
         return true;
     } else if (mHeaderPolicy->getExtendedRegionSize() + mDictBuffer->getUsedAdditionalBufferSize()
@@ -354,7 +354,7 @@
     std::vector<int> codePointVector(ptNodeParams.getCodePoints(),
             ptNodeParams.getCodePoints() + ptNodeParams.getCodePointCount());
     const ProbabilityEntry probabilityEntry =
-            mBuffers.get()->getProbabilityDictContent()->getProbabilityEntry(
+            mBuffers->getProbabilityDictContent()->getProbabilityEntry(
                     ptNodeParams.getTerminalId());
     const HistoricalInfo *const historicalInfo = probabilityEntry.getHistoricalInfo();
     // Fetch bigram information.
@@ -362,9 +362,9 @@
     const int bigramListPos = getBigramsPositionOfPtNode(ptNodePos);
     if (bigramListPos != NOT_A_DICT_POS) {
         int bigramWord1CodePoints[MAX_WORD_LENGTH];
-        const BigramDictContent *const bigramDictContent = mBuffers.get()->getBigramDictContent();
+        const BigramDictContent *const bigramDictContent = mBuffers->getBigramDictContent();
         const TerminalPositionLookupTable *const terminalPositionLookupTable =
-                mBuffers.get()->getTerminalPositionLookupTable();
+                mBuffers->getTerminalPositionLookupTable();
         bool hasNext = true;
         int readingPos = bigramListPos;
         while (hasNext) {
@@ -400,7 +400,7 @@
     if (shortcutPos != NOT_A_DICT_POS) {
         int shortcutTarget[MAX_WORD_LENGTH];
         const ShortcutDictContent *const shortcutDictContent =
-                mBuffers.get()->getShortcutDictContent();
+                mBuffers->getShortcutDictContent();
         bool hasNext = true;
         while (hasNext) {
             int shortcutTargetLength = 0;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h
index 639c153..cffb1f6 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h
@@ -37,17 +37,16 @@
 class DicNode;
 class DicNodeVector;
 
-// TODO: Implement.
 class Ver4PatriciaTriePolicy : public DictionaryStructureWithBufferPolicy {
  public:
-    Ver4PatriciaTriePolicy(const Ver4DictBuffers::Ver4DictBuffersPtr &buffers)
-            : mBuffers(buffers), mHeaderPolicy(mBuffers.get()->getHeaderPolicy()),
-              mDictBuffer(mBuffers.get()->getWritableTrieBuffer()),
-              mBigramPolicy(mBuffers.get()->getMutableBigramDictContent(),
-                      mBuffers.get()->getTerminalPositionLookupTable(), mHeaderPolicy),
-              mShortcutPolicy(mBuffers.get()->getMutableShortcutDictContent(),
-                      mBuffers.get()->getTerminalPositionLookupTable()),
-              mNodeReader(mDictBuffer, mBuffers.get()->getProbabilityDictContent(), mHeaderPolicy),
+    Ver4PatriciaTriePolicy(Ver4DictBuffers::Ver4DictBuffersPtr buffers)
+            : mBuffers(std::move(buffers)), mHeaderPolicy(mBuffers->getHeaderPolicy()),
+              mDictBuffer(mBuffers->getWritableTrieBuffer()),
+              mBigramPolicy(mBuffers->getMutableBigramDictContent(),
+                      mBuffers->getTerminalPositionLookupTable(), mHeaderPolicy),
+              mShortcutPolicy(mBuffers->getMutableShortcutDictContent(),
+                      mBuffers->getTerminalPositionLookupTable()),
+              mNodeReader(mDictBuffer, mBuffers->getProbabilityDictContent(), mHeaderPolicy),
               mPtNodeArrayReader(mDictBuffer),
               mNodeWriter(mDictBuffer, mBuffers.get(), mHeaderPolicy, &mNodeReader,
                       &mPtNodeArrayReader, &mBigramPolicy, &mShortcutPolicy),
@@ -132,7 +131,7 @@
     static const int MARGIN_TO_REFUSE_DYNAMIC_OPERATIONS;
     static const int MIN_DICT_SIZE_TO_REFUSE_DYNAMIC_OPERATIONS;
 
-    Ver4DictBuffers::Ver4DictBuffersPtr mBuffers;
+    const Ver4DictBuffers::Ver4DictBuffersPtr mBuffers;
     const HeaderPolicy *const mHeaderPolicy;
     BufferWithExtendableBuffer *const mDictBuffer;
     Ver4BigramListPolicy mBigramPolicy;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.cpp
index 3907c84..2b1f60e 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.cpp
@@ -67,7 +67,7 @@
             unigramCount, bigramCount, 0 /* extendedRegionSize */, &headerBuffer)) {
         return false;
     }
-    return dictBuffers.get()->flushHeaderAndDictBuffers(dictDirPath, &headerBuffer);
+    return dictBuffers->flushHeaderAndDictBuffers(dictDirPath, &headerBuffer);
 }
 
 bool Ver4PatriciaTrieWritingHelper::runGC(const int rootPtNodeArrayPos,
diff --git a/native/jni/src/suggest/policyimpl/dictionary/utils/dict_file_writing_utils.cpp b/native/jni/src/suggest/policyimpl/dictionary/utils/dict_file_writing_utils.cpp
index faef720..4459e86 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/utils/dict_file_writing_utils.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/utils/dict_file_writing_utils.cpp
@@ -48,17 +48,17 @@
         const std::vector<int> localeAsCodePointVector,
         const DictionaryHeaderStructurePolicy::AttributeMap *const attributeMap) {
     HeaderPolicy headerPolicy(FormatUtils::VERSION_4, localeAsCodePointVector, attributeMap);
-    Ver4DictBuffers::Ver4DictBuffersPtr dictBuffers =
-            Ver4DictBuffers::createVer4DictBuffers(&headerPolicy);
+    Ver4DictBuffers::Ver4DictBuffersPtr dictBuffers(
+            Ver4DictBuffers::createVer4DictBuffers(&headerPolicy));
     headerPolicy.fillInAndWriteHeaderToBuffer(true /* updatesLastDecayedTime */,
             0 /* unigramCount */, 0 /* bigramCount */,
-            0 /* extendedRegionSize */, dictBuffers.get()->getWritableHeaderBuffer());
+            0 /* extendedRegionSize */, dictBuffers->getWritableHeaderBuffer());
     if (!DynamicPtWritingUtils::writeEmptyDictionary(
-            dictBuffers.get()->getWritableTrieBuffer(), 0 /* rootPos */)) {
+            dictBuffers->getWritableTrieBuffer(), 0 /* rootPos */)) {
         AKLOGE("Empty ver4 dictionary structure cannot be created on memory.");
         return false;
     }
-    return dictBuffers.get()->flush(dirPath);
+    return dictBuffers->flush(dirPath);
 }
 
 /* static */ bool DictFileWritingUtils::flushAllHeaderAndBodyToFile(const char *const filePath,
diff --git a/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.cpp b/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.cpp
index e88d6e0..d3e0c23 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.cpp
@@ -33,7 +33,7 @@
     const int mmapFd = open(path, O_RDONLY);
     if (mmapFd < 0) {
         AKLOGE("DICT: Can't open the source. path=%s errno=%d", path, errno);
-        return MmappedBufferPtr(0);
+        return MmappedBufferPtr(nullptr);
     }
     const int pagesize = sysconf(_SC_PAGESIZE);
     const int offset = bufferOffset % pagesize;
@@ -45,13 +45,13 @@
     if (mmappedBuffer == MAP_FAILED) {
         AKLOGE("DICT: Can't mmap dictionary. errno=%d", errno);
         close(mmapFd);
-        return MmappedBufferPtr(0);
+        return MmappedBufferPtr(nullptr);
     }
     uint8_t *const buffer = static_cast<uint8_t *>(mmappedBuffer) + offset;
     if (!buffer) {
         AKLOGE("DICT: buffer is null");
         close(mmapFd);
-        return MmappedBufferPtr(0);
+        return MmappedBufferPtr(nullptr);
     }
     return MmappedBufferPtr(new MmappedBuffer(buffer, bufferSize, mmappedBuffer, alignedSize,
             mmapFd, isUpdatable));
@@ -61,7 +61,7 @@
         const char *const path, const bool isUpdatable) {
     const int fileSize = FileUtils::getFileSize(path);
     if (fileSize == -1) {
-        return MmappedBufferPtr(0);
+        return MmappedBufferPtr(nullptr);
     } else if (fileSize == 0) {
         return MmappedBufferPtr(new MmappedBuffer(isUpdatable));
     } else {
@@ -76,7 +76,7 @@
     const int filePathLength = snprintf(filePath, filePathBufferSize, "%s%s", dirPath,
             fileName);
     if (filePathLength >= filePathBufferSize) {
-        return 0;
+        return MmappedBufferPtr(nullptr);
     }
     return openBuffer(filePath, isUpdatable);
 }
diff --git a/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.h b/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.h
index 27ec4b2..f73716c 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/utils/mmapped_buffer.h
@@ -17,16 +17,16 @@
 #ifndef LATINIME_MMAPPED_BUFFER_H
 #define LATINIME_MMAPPED_BUFFER_H
 
+#include <memory>
 #include <stdint.h>
 
 #include "defines.h"
-#include "utils/exclusive_ownership_pointer.h"
 
 namespace latinime {
 
 class MmappedBuffer {
  public:
-    typedef ExclusiveOwnershipPointer<MmappedBuffer> MmappedBufferPtr;
+    typedef std::unique_ptr<const MmappedBuffer> MmappedBufferPtr;
 
     static MmappedBufferPtr openBuffer(const char *const path,
             const int bufferOffset, const int bufferSize, const bool isUpdatable);
diff --git a/native/jni/src/utils/exclusive_ownership_pointer.h b/native/jni/src/utils/exclusive_ownership_pointer.h
deleted file mode 100644
index 081802e..0000000
--- a/native/jni/src/utils/exclusive_ownership_pointer.h
+++ /dev/null
@@ -1,81 +0,0 @@
-/*
- * 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_EXCLUSIVE_OWNERSHIP_POINTER_H
-#define LATINIME_EXCLUSIVE_OWNERSHIP_POINTER_H
-
-#include "defines.h"
-
-namespace latinime {
-
-template<class T>
-class ExclusiveOwnershipPointer {
- public:
-    // This instance become an owner of the raw pointer.
-    AK_FORCE_INLINE ExclusiveOwnershipPointer(T *const rawPointer)
-            : mPointer(rawPointer),
-              mSharedOwnerPtr(new (ExclusiveOwnershipPointer<T> *)(this)) {}
-
-    // Move the ownership.
-    AK_FORCE_INLINE ExclusiveOwnershipPointer(const ExclusiveOwnershipPointer<T> &pointer)
-            : mPointer(pointer.mPointer), mSharedOwnerPtr(pointer.mSharedOwnerPtr) {
-        transferOwnership(&pointer);
-    }
-
-    AK_FORCE_INLINE ~ExclusiveOwnershipPointer() {
-        deletePointersIfHavingOwnership();
-    }
-
-    AK_FORCE_INLINE T *get() const {
-        return mPointer;
-    }
-
- private:
-    // This class allows to copy and ensures only one instance has the ownership of the
-    // managed pointer.
-    DISALLOW_DEFAULT_CONSTRUCTOR(ExclusiveOwnershipPointer);
-    DISALLOW_ASSIGNMENT_OPERATOR(ExclusiveOwnershipPointer);
-
-    void transferOwnership(const ExclusiveOwnershipPointer<T> *const src) {
-        if (*mSharedOwnerPtr != src) {
-           AKLOGE("Failed to transfer the ownership because src is not the current owner."
-                   "src: %p, owner: %p", src, *mSharedOwnerPtr);
-           ASSERT(false);
-           return;
-        }
-        // Transfer the ownership from src to this instance.
-        *mSharedOwnerPtr = this;
-    }
-
-    void deletePointersIfHavingOwnership() {
-        if (mSharedOwnerPtr && *mSharedOwnerPtr == this) {
-            if (mPointer) {
-                if (DEBUG_DICT) {
-                    AKLOGI("Releasing pointer: %p", mPointer);
-                }
-                delete mPointer;
-            }
-            delete mSharedOwnerPtr;
-        }
-    }
-
-    T *mPointer;
-    // mSharedOwnerPtr points a shared memory space where the instance which has the ownership is
-    // stored.
-    ExclusiveOwnershipPointer<T> **mSharedOwnerPtr;
-};
-} // namespace latinime
-#endif /* LATINIME_EXCLUSIVE_OWNERSHIP_POINTER_H */
diff --git a/tests/src/com/android/inputmethod/latin/BinaryDictionaryTests.java b/tests/src/com/android/inputmethod/latin/BinaryDictionaryTests.java
index 4f9245c..d9c35c4 100644
--- a/tests/src/com/android/inputmethod/latin/BinaryDictionaryTests.java
+++ b/tests/src/com/android/inputmethod/latin/BinaryDictionaryTests.java
@@ -23,7 +23,7 @@
 
 import com.android.inputmethod.latin.makedict.CodePointUtils;
 import com.android.inputmethod.latin.makedict.FormatSpec;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
+import com.android.inputmethod.latin.makedict.WeightedString;
 import com.android.inputmethod.latin.makedict.WordProperty;
 import com.android.inputmethod.latin.utils.BinaryDictionaryUtils;
 import com.android.inputmethod.latin.utils.FileUtils;
diff --git a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java
index 80978df..4bf6174 100644
--- a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java
+++ b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java
@@ -28,7 +28,6 @@
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNode;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNodeArray;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
 import com.android.inputmethod.latin.utils.BinaryDictionaryUtils;
 import com.android.inputmethod.latin.utils.ByteArrayDictBuffer;
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/CombinedInputOutput.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/CombinedInputOutput.java
index b6795ea..2c60fc7 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/CombinedInputOutput.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/CombinedInputOutput.java
@@ -20,8 +20,8 @@
 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.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.makedict.ProbabilityInfo;
+import com.android.inputmethod.latin.makedict.WeightedString;
 import com.android.inputmethod.latin.makedict.WordProperty;
 import com.android.inputmethod.latin.utils.CombinedFormatUtils;
 
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java
index ce9b9f3..cd3d4d3 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java
@@ -18,7 +18,7 @@
 
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNode;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
+import com.android.inputmethod.latin.makedict.WeightedString;
 import com.android.inputmethod.latin.makedict.WordProperty;
 
 import java.util.Arrays;
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java
index 178df5c..9b2567f 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java
@@ -19,7 +19,7 @@
 import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.PtNode;
-import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
+import com.android.inputmethod.latin.makedict.WeightedString;
 import com.android.inputmethod.latin.makedict.WordProperty;
 
 import java.util.Arrays;
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java
index 2ac842a..b5d5239 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java
@@ -19,8 +19,8 @@
 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.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.makedict.ProbabilityInfo;
+import com.android.inputmethod.latin.makedict.WeightedString;
 import com.android.inputmethod.latin.makedict.WordProperty;
 
 import java.io.BufferedReader;