Merge "Change visibility to avoid synthetic accessor method"
diff --git a/native/src/correction.cpp b/native/src/correction.cpp
index 22ee75a..2da82dc 100644
--- a/native/src/correction.cpp
+++ b/native/src/correction.cpp
@@ -32,48 +32,6 @@
 // edit distance funcitons //
 /////////////////////////////
 
-#if 0 /* no longer used */
-inline static int editDistance(
-        int* editDistanceTable, const unsigned short* input,
-        const int inputLength, const unsigned short* output, const int outputLength) {
-    // dp[li][lo] dp[a][b] = dp[ a * lo + b]
-    int* dp = editDistanceTable;
-    const int li = inputLength + 1;
-    const int lo = outputLength + 1;
-    for (int i = 0; i < li; ++i) {
-        dp[lo * i] = i;
-    }
-    for (int i = 0; i < lo; ++i) {
-        dp[i] = i;
-    }
-
-    for (int i = 0; i < li - 1; ++i) {
-        for (int j = 0; j < lo - 1; ++j) {
-            const uint32_t ci = toBaseLowerCase(input[i]);
-            const uint32_t co = toBaseLowerCase(output[j]);
-            const uint16_t cost = (ci == co) ? 0 : 1;
-            dp[(i + 1) * lo + (j + 1)] = min(dp[i * lo + (j + 1)] + 1,
-                    min(dp[(i + 1) * lo + j] + 1, dp[i * lo + j] + cost));
-            if (i > 0 && j > 0 && ci == toBaseLowerCase(output[j - 1])
-                    && co == toBaseLowerCase(input[i - 1])) {
-                dp[(i + 1) * lo + (j + 1)] = min(
-                        dp[(i + 1) * lo + (j + 1)], dp[(i - 1) * lo + (j - 1)] + cost);
-            }
-        }
-    }
-
-    if (DEBUG_EDIT_DISTANCE) {
-        LOGI("IN = %d, OUT = %d", inputLength, outputLength);
-        for (int i = 0; i < li; ++i) {
-            for (int j = 0; j < lo; ++j) {
-                LOGI("EDIT[%d][%d], %d", i, j, dp[i * lo + j]);
-            }
-        }
-    }
-    return dp[li * lo - 1];
-}
-#endif
-
 inline static void initEditDistance(int *editDistanceTable) {
     for (int i = 0; i <= MAX_WORD_LENGTH_INTERNAL; ++i) {
         editDistanceTable[i] = i;
@@ -145,7 +103,7 @@
 
 void Correction::setCorrectionParams(const int skipPos, const int excessivePos,
         const int transposedPos, const int spaceProximityPos, const int missingSpacePos,
-        const bool useFullEditDistance) {
+        const bool useFullEditDistance, const bool doAutoCompletion, const int maxErrors) {
     // TODO: remove
     mTransposedPos = transposedPos;
     mExcessivePos = excessivePos;
@@ -158,6 +116,8 @@
     mSpaceProximityPos = spaceProximityPos;
     mMissingSpacePos = missingSpacePos;
     mUseFullEditDistance = useFullEditDistance;
+    mDoAutoCompletion = doAutoCompletion;
+    mMaxErrors = maxErrors;
 }
 
 void Correction::checkState() {
@@ -279,7 +239,9 @@
 
 bool Correction::needsToPrune() const {
     // TODO: use edit distance here
-    return mOutputIndex - 1 >= mMaxDepth || mProximityCount > mMaxEditDistance;
+    return mOutputIndex - 1 >= mMaxDepth || mProximityCount > mMaxEditDistance
+            // Allow one char longer word for missing character
+            || (!mDoAutoCompletion && (mOutputIndex + 1 >= mInputLength));
 }
 
 void Correction::addCharToCurrentWord(const int32_t c) {
@@ -311,12 +273,17 @@
 Correction::CorrectionType Correction::processCharAndCalcState(
         const int32_t c, const bool isTerminal) {
     const int correctionCount = (mSkippedCount + mExcessiveCount + mTransposedCount);
+    if (correctionCount > mMaxErrors) {
+        return UNRELATED;
+    }
+
     // TODO: Change the limit if we'll allow two or more corrections
     const bool noCorrectionsHappenedSoFar = correctionCount == 0;
     const bool canTryCorrection = noCorrectionsHappenedSoFar;
     int proximityIndex = 0;
     mDistances[mOutputIndex] = NOT_A_DISTANCE;
 
+    // Skip checking this node
     if (mNeedsToTraverseAllNodes || isQuote(c)) {
         bool incremented = false;
         if (mLastCharExceeded && mInputIndex == mInputLength - 1) {
@@ -341,6 +308,7 @@
         return processSkipChar(c, isTerminal, incremented);
     }
 
+    // Check possible corrections.
     if (mExcessivePos >= 0) {
         if (mExcessiveCount == 0 && mExcessivePos < mOutputIndex) {
             mExcessivePos = mOutputIndex;
@@ -391,7 +359,12 @@
     }
 
     // TODO: Change the limit if we'll allow two or more proximity chars with corrections
-    const bool checkProximityChars = noCorrectionsHappenedSoFar ||  mProximityCount == 0;
+    // Work around: When the mMaxErrors is 1, we only allow just one error
+    // including proximity correction.
+    const bool checkProximityChars = (mMaxErrors > 1)
+            ? (noCorrectionsHappenedSoFar || mProximityCount == 0)
+            : (noCorrectionsHappenedSoFar && mProximityCount == 0);
+
     ProximityInfo::ProximityType matchedProximityCharId = secondTransposing
             ? ProximityInfo::EQUIVALENT_CHAR
             : mProximityInfo->getMatchedProximityId(
@@ -931,4 +904,46 @@
     return totalFreq;
 }
 
+#if 0 /* no longer used. keep just for reference */
+inline static int editDistance(
+        int* editDistanceTable, const unsigned short* input,
+        const int inputLength, const unsigned short* output, const int outputLength) {
+    // dp[li][lo] dp[a][b] = dp[ a * lo + b]
+    int* dp = editDistanceTable;
+    const int li = inputLength + 1;
+    const int lo = outputLength + 1;
+    for (int i = 0; i < li; ++i) {
+        dp[lo * i] = i;
+    }
+    for (int i = 0; i < lo; ++i) {
+        dp[i] = i;
+    }
+
+    for (int i = 0; i < li - 1; ++i) {
+        for (int j = 0; j < lo - 1; ++j) {
+            const uint32_t ci = toBaseLowerCase(input[i]);
+            const uint32_t co = toBaseLowerCase(output[j]);
+            const uint16_t cost = (ci == co) ? 0 : 1;
+            dp[(i + 1) * lo + (j + 1)] = min(dp[i * lo + (j + 1)] + 1,
+                    min(dp[(i + 1) * lo + j] + 1, dp[i * lo + j] + cost));
+            if (i > 0 && j > 0 && ci == toBaseLowerCase(output[j - 1])
+                    && co == toBaseLowerCase(input[i - 1])) {
+                dp[(i + 1) * lo + (j + 1)] = min(
+                        dp[(i + 1) * lo + (j + 1)], dp[(i - 1) * lo + (j - 1)] + cost);
+            }
+        }
+    }
+
+    if (DEBUG_EDIT_DISTANCE) {
+        LOGI("IN = %d, OUT = %d", inputLength, outputLength);
+        for (int i = 0; i < li; ++i) {
+            for (int j = 0; j < lo; ++j) {
+                LOGI("EDIT[%d][%d], %d", i, j, dp[i * lo + j]);
+            }
+        }
+    }
+    return dp[li * lo - 1];
+}
+#endif
+
 } // namespace latinime
diff --git a/native/src/correction.h b/native/src/correction.h
index d4e99f0..e55be8d 100644
--- a/native/src/correction.h
+++ b/native/src/correction.h
@@ -44,7 +44,8 @@
 
     // TODO: remove
     void setCorrectionParams(const int skipPos, const int excessivePos, const int transposedPos,
-            const int spaceProximityPos, const int missingSpacePos, const bool useFullEditDistance);
+            const int spaceProximityPos, const int missingSpacePos, const bool useFullEditDistance,
+            const bool doAutoCompletion, const int maxErrors);
     void checkState();
     bool initProcessState(const int index);
 
@@ -109,6 +110,7 @@
     const ProximityInfo *mProximityInfo;
 
     bool mUseFullEditDistance;
+    bool mDoAutoCompletion;
     int mMaxEditDistance;
     int mMaxDepth;
     int mInputLength;
@@ -116,6 +118,7 @@
     int mMissingSpacePos;
     int mTerminalInputIndex;
     int mTerminalOutputIndex;
+    int mMaxErrors;
 
     // The following arrays are state buffer.
     unsigned short mWord[MAX_WORD_LENGTH_INTERNAL];
diff --git a/native/src/defines.h b/native/src/defines.h
index ea643bf..e1d2ca3 100644
--- a/native/src/defines.h
+++ b/native/src/defines.h
@@ -202,6 +202,10 @@
 // This is only used for the size of array. Not to be used in c functions.
 #define MAX_WORD_LENGTH_INTERNAL 48
 
+// Word limit for sub queues used in WordsPriorityQueuePool.  Sub queues are temporary queues used
+// for better performance.
+#define SUB_QUEUE_MAX_WORDS 5
+
 #define MAX_DEPTH_MULTIPLIER 3
 
 // TODO: Reduce this constant if possible; check the maximum number of umlauts in the same German
diff --git a/native/src/dictionary.cpp b/native/src/dictionary.cpp
index 55358ec..e3673d4 100644
--- a/native/src/dictionary.cpp
+++ b/native/src/dictionary.cpp
@@ -39,7 +39,8 @@
         }
     }
     mCorrection = new Correction(typedLetterMultiplier, fullWordMultiplier);
-    mWordsPriorityQueue = new WordsPriorityQueue(maxWords, maxWordLength);
+    mWordsPriorityQueuePool = new WordsPriorityQueuePool(
+            maxWords, SUB_QUEUE_MAX_WORDS, maxWordLength);
     mUnigramDictionary = new UnigramDictionary(mDict, typedLetterMultiplier, fullWordMultiplier,
             maxWordLength, maxWords, maxAlternatives, IS_LATEST_DICT_VERSION);
     mBigramDictionary = new BigramDictionary(mDict, maxWordLength, maxAlternatives,
@@ -48,7 +49,7 @@
 
 Dictionary::~Dictionary() {
     delete mCorrection;
-    delete mWordsPriorityQueue;
+    delete mWordsPriorityQueuePool;
     delete mUnigramDictionary;
     delete mBigramDictionary;
 }
diff --git a/native/src/dictionary.h b/native/src/dictionary.h
index 2a6e4e0..52048ec 100644
--- a/native/src/dictionary.h
+++ b/native/src/dictionary.h
@@ -23,7 +23,7 @@
 #include "defines.h"
 #include "proximity_info.h"
 #include "unigram_dictionary.h"
-#include "words_priority_queue.h"
+#include "words_priority_queue_pool.h"
 
 namespace latinime {
 
@@ -34,7 +34,7 @@
 
     int getSuggestions(ProximityInfo *proximityInfo, int *xcoordinates, int *ycoordinates,
             int *codes, int codesSize, int flags, unsigned short *outWords, int *frequencies) {
-        return mUnigramDictionary->getSuggestions(proximityInfo, mWordsPriorityQueue,
+        return mUnigramDictionary->getSuggestions(proximityInfo, mWordsPriorityQueuePool,
                 mCorrection, xcoordinates, ycoordinates, codes,
                 codesSize, flags, outWords, frequencies);
     }
@@ -81,7 +81,7 @@
     const bool IS_LATEST_DICT_VERSION;
     UnigramDictionary *mUnigramDictionary;
     BigramDictionary *mBigramDictionary;
-    WordsPriorityQueue *mWordsPriorityQueue;
+    WordsPriorityQueuePool *mWordsPriorityQueuePool;
     Correction *mCorrection;
 };
 
diff --git a/native/src/unigram_dictionary.cpp b/native/src/unigram_dictionary.cpp
index a2c1f72..0db33e7 100644
--- a/native/src/unigram_dictionary.cpp
+++ b/native/src/unigram_dictionary.cpp
@@ -93,7 +93,7 @@
         const int *xcoordinates, const int *ycoordinates, const int *codesBuffer,
         const int codesBufferSize, const int flags, const int *codesSrc,
         const int codesRemain, const int currentDepth, int *codesDest, Correction *correction,
-        WordsPriorityQueue *queue) {
+        WordsPriorityQueuePool *queuePool) {
 
     if (currentDepth < MAX_UMLAUT_SEARCH_DEPTH) {
         for (int i = 0; i < codesRemain; ++i) {
@@ -110,7 +110,8 @@
                 getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates,
                         codesBuffer, codesBufferSize, flags,
                         codesSrc + (i + 1) * MAX_PROXIMITY_CHARS, codesRemain - i - 1,
-                        currentDepth + 1, codesDest + i * MAX_PROXIMITY_CHARS, correction, queue);
+                        currentDepth + 1, codesDest + i * MAX_PROXIMITY_CHARS, correction,
+                        queuePool);
 
                 // Copy the second char of the digraph in place, then continue processing on
                 // the remaining part of the word.
@@ -120,7 +121,7 @@
                 getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates,
                         codesBuffer, codesBufferSize, flags,
                         codesSrc + i * MAX_PROXIMITY_CHARS, codesRemain - i, currentDepth + 1,
-                        codesDest + i * MAX_PROXIMITY_CHARS, correction, queue);
+                        codesDest + i * MAX_PROXIMITY_CHARS, correction, queuePool);
                 return;
             }
         }
@@ -137,27 +138,28 @@
 
     getWordSuggestions(proximityInfo, xcoordinates, ycoordinates, codesBuffer,
             (codesDest - codesBuffer) / MAX_PROXIMITY_CHARS + codesRemain, flags, correction,
-            queue);
+            queuePool);
 }
 
-int UnigramDictionary::getSuggestions(ProximityInfo *proximityInfo, WordsPriorityQueue *queue,
-        Correction *correction, const int *xcoordinates, const int *ycoordinates, const int *codes,
-        const int codesSize, const int flags, unsigned short *outWords, int *frequencies) {
+int UnigramDictionary::getSuggestions(ProximityInfo *proximityInfo,
+        WordsPriorityQueuePool *queuePool, Correction *correction, const int *xcoordinates,
+        const int *ycoordinates, const int *codes, const int codesSize, const int flags,
+        unsigned short *outWords, int *frequencies) {
 
-    WordsPriorityQueue* masterQueue = queue;
     Correction* masterCorrection = correction;
     if (REQUIRES_GERMAN_UMLAUT_PROCESSING & flags)
     { // Incrementally tune the word and try all possibilities
         int codesBuffer[getCodesBufferSize(codes, codesSize, MAX_PROXIMITY_CHARS)];
         getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates, codesBuffer,
-                codesSize, flags, codes, codesSize, 0, codesBuffer, masterCorrection, masterQueue);
+                codesSize, flags, codes, codesSize, 0, codesBuffer, masterCorrection, queuePool);
     } else { // Normal processing
         getWordSuggestions(proximityInfo, xcoordinates, ycoordinates, codes, codesSize, flags,
-                masterCorrection, masterQueue);
+                masterCorrection, queuePool);
     }
 
     PROF_START(20);
-    const int suggestedWordsCount = masterQueue->outputSuggestions(frequencies, outWords);
+    const int suggestedWordsCount =
+            queuePool->getMasterQueue()->outputSuggestions(frequencies, outWords);
 
     if (DEBUG_DICT) {
         LOGI("Returning %d words", suggestedWordsCount);
@@ -178,11 +180,13 @@
 
 void UnigramDictionary::getWordSuggestions(ProximityInfo *proximityInfo,
         const int *xcoordinates, const int *ycoordinates, const int *codes,
-        const int inputLength, const int flags, Correction *correction, WordsPriorityQueue *queue) {
+        const int inputLength, const int flags, Correction *correction,
+        WordsPriorityQueuePool *queuePool) {
+    WordsPriorityQueue *masterQueue = queuePool->getMasterQueue();
 
     PROF_OPEN;
     PROF_START(0);
-    initSuggestions(proximityInfo, xcoordinates, ycoordinates, codes, inputLength, queue);
+    initSuggestions(proximityInfo, xcoordinates, ycoordinates, codes, inputLength, masterQueue);
     if (DEBUG_DICT) assert(codesSize == inputLength);
 
     const int maxDepth = min(inputLength * MAX_DEPTH_MULTIPLIER, MAX_WORD_LENGTH);
@@ -192,7 +196,7 @@
     const bool useFullEditDistance = USE_FULL_EDIT_DISTANCE & flags;
     // TODO: remove
     PROF_START(1);
-    getSuggestionCandidates(useFullEditDistance, inputLength, correction, queue);
+    getSuggestionCandidates(useFullEditDistance, inputLength, correction, masterQueue);
     PROF_END(1);
 
     PROF_START(2);
@@ -216,7 +220,7 @@
                 LOGI("--- Suggest missing space characters %d", i);
             }
             getMissingSpaceWords(
-                    inputLength, i, proximityInfo, correction, useFullEditDistance, queue);
+                    inputLength, i, proximityInfo, correction, useFullEditDistance, queuePool);
         }
     }
     PROF_END(5);
@@ -235,8 +239,8 @@
                         i, x, y, proximityInfo->hasSpaceProximity(x, y));
             }
             if (proximityInfo->hasSpaceProximity(x, y)) {
-                getMistypedSpaceWords(
-                        inputLength, i, proximityInfo, correction, useFullEditDistance, queue);
+                getMistypedSpaceWords(inputLength, i, proximityInfo, correction,
+                        useFullEditDistance, queuePool);
             }
         }
     }
@@ -260,7 +264,8 @@
         const int inputLength, Correction *correction, WordsPriorityQueue *queue) {
     // TODO: Remove setCorrectionParams
     correction->setCorrectionParams(0, 0, 0,
-            -1 /* spaceProximityPos */, -1 /* missingSpacePos */, useFullEditDistance);
+            -1 /* spaceProximityPos */, -1 /* missingSpacePos */, useFullEditDistance,
+            true /* doAutoCompletion */, DEFAULT_MAX_ERRORS);
     int rootPosition = ROOT_POS;
     // Get the number of children of root, then increment the position
     int childCount = Dictionary::getCount(DICT_ROOT, &rootPosition);
@@ -292,20 +297,20 @@
 
 void UnigramDictionary::getMissingSpaceWords(
         const int inputLength, const int missingSpacePos, ProximityInfo *proximityInfo,
-        Correction *correction, const bool useFullEditDistance, WordsPriorityQueue *queue) {
+        Correction *correction, const bool useFullEditDistance, WordsPriorityQueuePool *queuePool) {
     correction->setCorrectionParams(-1 /* skipPos */, -1 /* excessivePos */,
             -1 /* transposedPos */, -1 /* spaceProximityPos */, missingSpacePos,
-            useFullEditDistance);
-    getSplitTwoWordsSuggestion(inputLength, proximityInfo, correction, queue);
+            useFullEditDistance, false /* doAutoCompletion */, MAX_ERRORS_FOR_TWO_WORDS);
+    getSplitTwoWordsSuggestion(inputLength, proximityInfo, correction, queuePool);
 }
 
 void UnigramDictionary::getMistypedSpaceWords(
         const int inputLength, const int spaceProximityPos, ProximityInfo *proximityInfo,
-        Correction *correction, const bool useFullEditDistance, WordsPriorityQueue *queue) {
+        Correction *correction, const bool useFullEditDistance, WordsPriorityQueuePool *queuePool) {
     correction->setCorrectionParams(-1 /* skipPos */, -1 /* excessivePos */,
             -1 /* transposedPos */, spaceProximityPos, -1 /* missingSpacePos */,
-            useFullEditDistance);
-    getSplitTwoWordsSuggestion(inputLength, proximityInfo, correction, queue);
+            useFullEditDistance, false /* doAutoCompletion */, MAX_ERRORS_FOR_TWO_WORDS);
+    getSplitTwoWordsSuggestion(inputLength, proximityInfo, correction, queuePool);
 }
 
 inline void UnigramDictionary::onTerminal(
@@ -320,7 +325,9 @@
 
 void UnigramDictionary::getSplitTwoWordsSuggestion(
         const int inputLength, ProximityInfo *proximityInfo, Correction *correction,
-        WordsPriorityQueue *queue) {
+        WordsPriorityQueuePool *queuePool) {
+    WordsPriorityQueue *masterQueue = queuePool->getMasterQueue();
+
     const int spaceProximityPos = correction->getSpaceProximityPos();
     const int missingSpacePos = correction->getMissingSpacePos();
     if (DEBUG_DICT) {
@@ -372,7 +379,7 @@
     if (DEBUG_DICT) {
         LOGI("Split two words:  %d, %d, %d, %d", firstFreq, secondFreq, pairFreq, inputLength);
     }
-    addWord(word, newWordLength, pairFreq, queue);
+    addWord(word, newWordLength, pairFreq, masterQueue);
     return;
 }
 
@@ -585,7 +592,7 @@
         if (stateType == Correction::TRAVERSE_ALL_ON_TERMINAL
                 || stateType == Correction::ON_TERMINAL) {
             needsToInvokeOnTerminal = true;
-        } else if (stateType == Correction::UNRELATED) {
+        } else if (stateType == Correction::UNRELATED || correction->needsToPrune()) {
             // We found that this is an unrelated character, so we should give up traversing
             // this node and its children entirely.
             // However we may not be on the last virtual node yet so we skip the remaining
diff --git a/native/src/unigram_dictionary.h b/native/src/unigram_dictionary.h
index 0b01265..ce15cdd 100644
--- a/native/src/unigram_dictionary.h
+++ b/native/src/unigram_dictionary.h
@@ -23,6 +23,7 @@
 #include "defines.h"
 #include "proximity_info.h"
 #include "words_priority_queue.h"
+#include "words_priority_queue_pool.h"
 
 namespace latinime {
 
@@ -61,12 +62,16 @@
     static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES = 0x20;
     static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES = 0x30;
 
+    // Error tolerances
+    static const int DEFAULT_MAX_ERRORS = 2;
+    static const int MAX_ERRORS_FOR_TWO_WORDS = 1;
+
     UnigramDictionary(const uint8_t* const streamStart, int typedLetterMultipler,
             int fullWordMultiplier, int maxWordLength, int maxWords, int maxProximityChars,
             const bool isLatestDictVersion);
     bool isValidWord(const uint16_t* const inWord, const int length) const;
     int getBigramPosition(int pos, unsigned short *word, int offset, int length) const;
-    int getSuggestions(ProximityInfo *proximityInfo, WordsPriorityQueue *queue,
+    int getSuggestions(ProximityInfo *proximityInfo, WordsPriorityQueuePool *queuePool,
             Correction *correction, const int *xcoordinates,
             const int *ycoordinates, const int *codes, const int codesSize, const int flags,
             unsigned short *outWords, int *frequencies);
@@ -76,13 +81,13 @@
 
     void getWordSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
             const int *ycoordinates, const int *codes, const int inputLength,
-            const int flags, Correction *correction, WordsPriorityQueue *queue);
+            const int flags, Correction *correction, WordsPriorityQueuePool *queuePool);
     bool isDigraph(const int *codes, const int i, const int codesSize) const;
     void getWordWithDigraphSuggestionsRec(ProximityInfo *proximityInfo,
         const int *xcoordinates, const int* ycoordinates, const int *codesBuffer,
         const int codesBufferSize, const int flags, const int* codesSrc,
         const int codesRemain, const int currentDepth, int* codesDest, Correction *correction,
-        WordsPriorityQueue* queue);
+        WordsPriorityQueuePool* queuePool);
     void initSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
             const int *ycoordinates, const int *codes, const int codesSize,
             WordsPriorityQueue *queue);
@@ -90,13 +95,13 @@
             const bool useFullEditDistance, const int inputLength, Correction *correction,
             WordsPriorityQueue* queue);
     void getSplitTwoWordsSuggestion(const int inputLength, ProximityInfo *proximityInfo,
-            Correction *correction, WordsPriorityQueue *queue);
+            Correction *correction, WordsPriorityQueuePool *queuePool);
     void getMissingSpaceWords(const int inputLength, const int missingSpacePos,
             ProximityInfo *proximityInfo, Correction *correction,
-            const bool useFullEditDistance, WordsPriorityQueue *queue);
+            const bool useFullEditDistance, WordsPriorityQueuePool *queuePool);
     void getMistypedSpaceWords(const int inputLength, const int spaceProximityPos,
             ProximityInfo *proximityInfo, Correction *correction,
-            const bool useFullEditDistance, WordsPriorityQueue *queue);
+            const bool useFullEditDistance, WordsPriorityQueuePool *queuePool);
     void onTerminal(const int freq, Correction *correction, WordsPriorityQueue *queue);
     bool needsToSkipCurrentNode(const unsigned short c,
             const int inputIndex, const int skipPos, const int depth);
diff --git a/native/src/words_priority_queue.h b/native/src/words_priority_queue.h
index 366b1b6..a4175d3 100644
--- a/native/src/words_priority_queue.h
+++ b/native/src/words_priority_queue.h
@@ -24,7 +24,7 @@
 namespace latinime {
 
 class WordsPriorityQueue {
-private:
+public:
     class SuggestedWord {
     public:
         int mScore;
@@ -40,31 +40,6 @@
         }
     };
 
-    struct wordComparator {
-        bool operator ()(SuggestedWord * left, SuggestedWord * right) {
-            return left->mScore > right->mScore;
-        }
-    };
-
-    SuggestedWord* getFreeSuggestedWord(int score, unsigned short* word,
-            int wordLength) {
-        for (unsigned int i = 0; i < MAX_WORD_LENGTH; ++i) {
-            if (!mSuggestedWords[i].mUsed) {
-                mSuggestedWords[i].setParams(score, word, wordLength);
-                return &mSuggestedWords[i];
-            }
-        }
-        return 0;
-    }
-
-    typedef std::priority_queue<SuggestedWord*, std::vector<SuggestedWord*>,
-            wordComparator> Suggestions;
-    Suggestions mSuggestions;
-    const unsigned int MAX_WORDS;
-    const unsigned int MAX_WORD_LENGTH;
-    SuggestedWord* mSuggestedWords;
-
-public:
     WordsPriorityQueue(int maxWords, int maxWordLength) :
             MAX_WORDS((unsigned int) maxWords), MAX_WORD_LENGTH(
                     (unsigned int) maxWordLength) {
@@ -105,6 +80,13 @@
         mSuggestions.push(sw);
     }
 
+    SuggestedWord* topAndPop() {
+        if (mSuggestions.empty()) return 0;
+        SuggestedWord* sw = mSuggestions.top();
+        mSuggestions.pop();
+        return sw;
+    }
+
     int outputSuggestions(int *frequencies, unsigned short *outputChars) {
         const unsigned int size = min(MAX_WORDS, mSuggestions.size());
         int index = size - 1;
@@ -140,6 +122,30 @@
             mSuggestions.pop();
         }
     }
+private:
+    struct wordComparator {
+        bool operator ()(SuggestedWord * left, SuggestedWord * right) {
+            return left->mScore > right->mScore;
+        }
+    };
+
+    SuggestedWord* getFreeSuggestedWord(int score, unsigned short* word,
+            int wordLength) {
+        for (unsigned int i = 0; i < MAX_WORD_LENGTH; ++i) {
+            if (!mSuggestedWords[i].mUsed) {
+                mSuggestedWords[i].setParams(score, word, wordLength);
+                return &mSuggestedWords[i];
+            }
+        }
+        return 0;
+    }
+
+    typedef std::priority_queue<SuggestedWord*, std::vector<SuggestedWord*>,
+            wordComparator> Suggestions;
+    Suggestions mSuggestions;
+    const unsigned int MAX_WORDS;
+    const unsigned int MAX_WORD_LENGTH;
+    SuggestedWord* mSuggestedWords;
 };
 }
 
diff --git a/native/src/words_priority_queue_pool.h b/native/src/words_priority_queue_pool.h
new file mode 100644
index 0000000..d964bfc
--- /dev/null
+++ b/native/src/words_priority_queue_pool.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef LATINIME_WORDS_PRIORITY_QUEUE_POOL_H
+#define LATINIME_WORDS_PRIORITY_QUEUE_POOL_H
+
+#include "words_priority_queue.h"
+
+namespace latinime {
+
+class WordsPriorityQueuePool {
+public:
+    WordsPriorityQueuePool(int mainQueueMaxWords, int subQueueMaxWords, int maxWordLength) {
+        mMasterQueue = new WordsPriorityQueue(mainQueueMaxWords, maxWordLength);
+        mSubQueue1 = new WordsPriorityQueue(subQueueMaxWords, maxWordLength);
+        mSubQueue2 = new WordsPriorityQueue(subQueueMaxWords, maxWordLength);
+    }
+
+    ~WordsPriorityQueuePool() {
+        delete mMasterQueue;
+    }
+
+    WordsPriorityQueue* getMasterQueue() {
+        return mMasterQueue;
+    }
+    // TODO: Come up with more generic pool
+    WordsPriorityQueue* getSubQueue1() {
+        return mSubQueue1;
+    }
+    WordsPriorityQueue* getSubQueue2() {
+        return mSubQueue2;
+    }
+private:
+    WordsPriorityQueue *mMasterQueue;
+    WordsPriorityQueue *mSubQueue1;
+    WordsPriorityQueue *mSubQueue2;
+};
+}
+
+#endif // LATINIME_WORDS_PRIORITY_QUEUE_POOL_H