| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.inputmethod.latin.makedict; |
| |
| import com.android.inputmethod.latin.makedict.BinaryDictDecoderUtils.CharEncoding; |
| 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 java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.Map.Entry; |
| |
| /** |
| * Encodes binary files for a FusionDictionary. |
| * |
| * All the methods in this class are static. |
| * |
| * TODO: Rename this class to DictEncoderUtils. |
| */ |
| public class BinaryDictEncoderUtils { |
| |
| private static final boolean DBG = MakedictLog.DBG; |
| |
| private BinaryDictEncoderUtils() { |
| // This utility class is not publicly instantiable. |
| } |
| |
| // Arbitrary limit to how much passes we consider address size compression should |
| // terminate in. At the time of this writing, our largest dictionary completes |
| // compression in five passes. |
| // If the number of passes exceeds this number, makedict bails with an exception on |
| // suspicion that a bug might be causing an infinite loop. |
| private static final int MAX_PASSES = 24; |
| |
| /** |
| * Compute the binary size of the character array. |
| * |
| * If only one character, this is the size of this character. If many, it's the sum of their |
| * sizes + 1 byte for the terminator. |
| * |
| * @param characters the character array |
| * @return the size of the char array, including the terminator if any |
| */ |
| static int getPtNodeCharactersSize(final int[] characters, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| int size = CharEncoding.getCharArraySize(characters, codePointToOneByteCodeMap); |
| if (characters.length > 1) size += FormatSpec.PTNODE_TERMINATOR_SIZE; |
| return size; |
| } |
| |
| /** |
| * Compute the binary size of the character array in a PtNode |
| * |
| * If only one character, this is the size of this character. If many, it's the sum of their |
| * sizes + 1 byte for the terminator. |
| * |
| * @param ptNode the PtNode |
| * @return the size of the char array, including the terminator if any |
| */ |
| private static int getPtNodeCharactersSize(final PtNode ptNode, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| return getPtNodeCharactersSize(ptNode.mChars, codePointToOneByteCodeMap); |
| } |
| |
| /** |
| * Compute the binary size of the PtNode count for a node array. |
| * @param nodeArray the nodeArray |
| * @return the size of the PtNode count, either 1 or 2 bytes. |
| */ |
| private static int getPtNodeCountSize(final PtNodeArray nodeArray) { |
| return BinaryDictIOUtils.getPtNodeCountSize(nodeArray.mData.size()); |
| } |
| |
| /** |
| * Compute the maximum size of a PtNode, assuming 3-byte addresses for everything. |
| * |
| * @param ptNode the PtNode to compute the size of. |
| * @return the maximum size of the PtNode. |
| */ |
| private static int getPtNodeMaximumSize(final PtNode ptNode, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| int size = getNodeHeaderSize(ptNode, codePointToOneByteCodeMap); |
| if (ptNode.isTerminal()) { |
| // If terminal, one byte for the frequency. |
| size += FormatSpec.PTNODE_FREQUENCY_SIZE; |
| } |
| size += FormatSpec.PTNODE_MAX_ADDRESS_SIZE; // For children address |
| if (null != ptNode.mBigrams) { |
| size += (FormatSpec.PTNODE_ATTRIBUTE_FLAGS_SIZE |
| + FormatSpec.PTNODE_ATTRIBUTE_MAX_ADDRESS_SIZE) |
| * ptNode.mBigrams.size(); |
| } |
| return size; |
| } |
| |
| /** |
| * Compute the maximum size of each PtNode of a PtNode array, assuming 3-byte addresses for |
| * everything, and caches it in the `mCachedSize' member of the nodes; deduce the size of |
| * the containing node array, and cache it it its 'mCachedSize' member. |
| * |
| * @param ptNodeArray the node array to compute the maximum size of. |
| */ |
| private static void calculatePtNodeArrayMaximumSize(final PtNodeArray ptNodeArray, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| int size = getPtNodeCountSize(ptNodeArray); |
| for (PtNode node : ptNodeArray.mData) { |
| final int nodeSize = getPtNodeMaximumSize(node, codePointToOneByteCodeMap); |
| node.mCachedSize = nodeSize; |
| size += nodeSize; |
| } |
| ptNodeArray.mCachedSize = size; |
| } |
| |
| /** |
| * Compute the size of the header (flag + [parent address] + characters size) of a PtNode. |
| * |
| * @param ptNode the PtNode of which to compute the size of the header |
| */ |
| private static int getNodeHeaderSize(final PtNode ptNode, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| return FormatSpec.PTNODE_FLAGS_SIZE + getPtNodeCharactersSize(ptNode, |
| codePointToOneByteCodeMap); |
| } |
| |
| /** |
| * Compute the size, in bytes, that an address will occupy. |
| * |
| * This can be used either for children addresses (which are always positive) or for |
| * attribute, which may be positive or negative but |
| * store their sign bit separately. |
| * |
| * @param address the address |
| * @return the byte size. |
| */ |
| static int getByteSize(final int address) { |
| assert(address <= FormatSpec.UINT24_MAX); |
| if (!BinaryDictIOUtils.hasChildrenAddress(address)) { |
| return 0; |
| } else if (Math.abs(address) <= FormatSpec.UINT8_MAX) { |
| return 1; |
| } else if (Math.abs(address) <= FormatSpec.UINT16_MAX) { |
| return 2; |
| } else { |
| return 3; |
| } |
| } |
| |
| static int writeUIntToBuffer(final byte[] buffer, final int fromPosition, final int value, |
| final int size) { |
| int position = fromPosition; |
| switch(size) { |
| case 4: |
| buffer[position++] = (byte) ((value >> 24) & 0xFF); |
| /* fall through */ |
| case 3: |
| buffer[position++] = (byte) ((value >> 16) & 0xFF); |
| /* fall through */ |
| case 2: |
| buffer[position++] = (byte) ((value >> 8) & 0xFF); |
| /* fall through */ |
| case 1: |
| buffer[position++] = (byte) (value & 0xFF); |
| break; |
| default: |
| /* nop */ |
| } |
| return position; |
| } |
| |
| static void writeUIntToStream(final OutputStream stream, final int value, final int size) |
| throws IOException { |
| switch(size) { |
| case 4: |
| stream.write((value >> 24) & 0xFF); |
| /* fall through */ |
| case 3: |
| stream.write((value >> 16) & 0xFF); |
| /* fall through */ |
| case 2: |
| stream.write((value >> 8) & 0xFF); |
| /* fall through */ |
| case 1: |
| stream.write(value & 0xFF); |
| break; |
| default: |
| /* nop */ |
| } |
| } |
| |
| // End utility methods |
| |
| // This method is responsible for finding a nice ordering of the nodes that favors run-time |
| // cache performance and dictionary size. |
| /* package for tests */ static ArrayList<PtNodeArray> flattenTree( |
| final PtNodeArray rootNodeArray) { |
| final int treeSize = FusionDictionary.countPtNodes(rootNodeArray); |
| MakedictLog.i("Counted nodes : " + treeSize); |
| final ArrayList<PtNodeArray> flatTree = new ArrayList<>(treeSize); |
| return flattenTreeInner(flatTree, rootNodeArray); |
| } |
| |
| private static ArrayList<PtNodeArray> flattenTreeInner(final ArrayList<PtNodeArray> list, |
| final PtNodeArray ptNodeArray) { |
| // Removing the node is necessary if the tails are merged, because we would then |
| // add the same node several times when we only want it once. A number of places in |
| // the code also depends on any node being only once in the list. |
| // Merging tails can only be done if there are no attributes. Searching for attributes |
| // in LatinIME code depends on a total breadth-first ordering, which merging tails |
| // breaks. If there are no attributes, it should be fine (and reduce the file size) |
| // to merge tails, and removing the node from the list would be necessary. However, |
| // we don't merge tails because breaking the breadth-first ordering would result in |
| // extreme overhead at bigram lookup time (it would make the search function O(n) instead |
| // of the current O(log(n)), where n=number of nodes in the dictionary which is pretty |
| // high). |
| // If no nodes are ever merged, we can't have the same node twice in the list, hence |
| // searching for duplicates in unnecessary. It is also very performance consuming, |
| // since `list' is an ArrayList so it's an O(n) operation that runs on all nodes, making |
| // this simple list.remove operation O(n*n) overall. On Android this overhead is very |
| // high. |
| // For future reference, the code to remove duplicate is a simple : list.remove(node); |
| list.add(ptNodeArray); |
| final ArrayList<PtNode> branches = ptNodeArray.mData; |
| for (PtNode ptNode : branches) { |
| if (null != ptNode.mChildren) flattenTreeInner(list, ptNode.mChildren); |
| } |
| return list; |
| } |
| |
| /** |
| * Get the offset from a position inside a current node array to a target node array, during |
| * update. |
| * |
| * If the current node array is before the target node array, the target node array has not |
| * been updated yet, so we should return the offset from the old position of the current node |
| * array to the old position of the target node array. If on the other hand the target is |
| * before the current node array, it already has been updated, so we should return the offset |
| * from the new position in the current node array to the new position in the target node |
| * array. |
| * |
| * @param currentNodeArray node array containing the PtNode where the offset will be written |
| * @param offsetFromStartOfCurrentNodeArray offset, in bytes, from the start of currentNodeArray |
| * @param targetNodeArray the target node array to get the offset to |
| * @return the offset to the target node array |
| */ |
| private static int getOffsetToTargetNodeArrayDuringUpdate(final PtNodeArray currentNodeArray, |
| final int offsetFromStartOfCurrentNodeArray, final PtNodeArray targetNodeArray) { |
| final boolean isTargetBeforeCurrent = (targetNodeArray.mCachedAddressBeforeUpdate |
| < currentNodeArray.mCachedAddressBeforeUpdate); |
| if (isTargetBeforeCurrent) { |
| return targetNodeArray.mCachedAddressAfterUpdate |
| - (currentNodeArray.mCachedAddressAfterUpdate |
| + offsetFromStartOfCurrentNodeArray); |
| } |
| return targetNodeArray.mCachedAddressBeforeUpdate |
| - (currentNodeArray.mCachedAddressBeforeUpdate + offsetFromStartOfCurrentNodeArray); |
| } |
| |
| /** |
| * Get the offset from a position inside a current node array to a target PtNode, during |
| * update. |
| * |
| * @param currentNodeArray node array containing the PtNode where the offset will be written |
| * @param offsetFromStartOfCurrentNodeArray offset, in bytes, from the start of currentNodeArray |
| * @param targetPtNode the target PtNode to get the offset to |
| * @return the offset to the target PtNode |
| */ |
| // TODO: is there any way to factorize this method with the one above? |
| private static int getOffsetToTargetPtNodeDuringUpdate(final PtNodeArray currentNodeArray, |
| final int offsetFromStartOfCurrentNodeArray, final PtNode targetPtNode) { |
| final int oldOffsetBasePoint = currentNodeArray.mCachedAddressBeforeUpdate |
| + offsetFromStartOfCurrentNodeArray; |
| final boolean isTargetBeforeCurrent = (targetPtNode.mCachedAddressBeforeUpdate |
| < oldOffsetBasePoint); |
| // If the target is before the current node array, then its address has already been |
| // updated. We can use the AfterUpdate member, and compare it to our own member after |
| // update. Otherwise, the AfterUpdate member is not updated yet, so we need to use the |
| // BeforeUpdate member, and of course we have to compare this to our own address before |
| // update. |
| if (isTargetBeforeCurrent) { |
| final int newOffsetBasePoint = currentNodeArray.mCachedAddressAfterUpdate |
| + offsetFromStartOfCurrentNodeArray; |
| return targetPtNode.mCachedAddressAfterUpdate - newOffsetBasePoint; |
| } |
| return targetPtNode.mCachedAddressBeforeUpdate - oldOffsetBasePoint; |
| } |
| |
| /** |
| * Computes the actual node array size, based on the cached addresses of the children nodes. |
| * |
| * Each node array stores its tentative address. During dictionary address computing, these |
| * are not final, but they can be used to compute the node array size (the node array size |
| * depends on the address of the children because the number of bytes necessary to store an |
| * address depends on its numeric value. The return value indicates whether the node array |
| * contents (as in, any of the addresses stored in the cache fields) have changed with |
| * respect to their previous value. |
| * |
| * @param ptNodeArray the node array to compute the size of. |
| * @param dict the dictionary in which the word/attributes are to be found. |
| * @return false if none of the cached addresses inside the node array changed, true otherwise. |
| */ |
| private static boolean computeActualPtNodeArraySize(final PtNodeArray ptNodeArray, |
| final FusionDictionary dict, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| boolean changed = false; |
| int size = getPtNodeCountSize(ptNodeArray); |
| for (PtNode ptNode : ptNodeArray.mData) { |
| ptNode.mCachedAddressAfterUpdate = ptNodeArray.mCachedAddressAfterUpdate + size; |
| if (ptNode.mCachedAddressAfterUpdate != ptNode.mCachedAddressBeforeUpdate) { |
| changed = true; |
| } |
| int nodeSize = getNodeHeaderSize(ptNode, codePointToOneByteCodeMap); |
| if (ptNode.isTerminal()) { |
| nodeSize += FormatSpec.PTNODE_FREQUENCY_SIZE; |
| } |
| if (null != ptNode.mChildren) { |
| nodeSize += getByteSize(getOffsetToTargetNodeArrayDuringUpdate(ptNodeArray, |
| nodeSize + size, ptNode.mChildren)); |
| } |
| if (null != ptNode.mBigrams) { |
| for (WeightedString bigram : ptNode.mBigrams) { |
| final int offset = getOffsetToTargetPtNodeDuringUpdate(ptNodeArray, |
| nodeSize + size + FormatSpec.PTNODE_ATTRIBUTE_FLAGS_SIZE, |
| FusionDictionary.findWordInTree(dict.mRootNodeArray, bigram.mWord)); |
| nodeSize += getByteSize(offset) + FormatSpec.PTNODE_ATTRIBUTE_FLAGS_SIZE; |
| } |
| } |
| ptNode.mCachedSize = nodeSize; |
| size += nodeSize; |
| } |
| if (ptNodeArray.mCachedSize != size) { |
| ptNodeArray.mCachedSize = size; |
| changed = true; |
| } |
| return changed; |
| } |
| |
| /** |
| * Initializes the cached addresses of node arrays and their containing nodes from their size. |
| * |
| * @param flatNodes the list of node arrays. |
| * @return the byte size of the entire stack. |
| */ |
| private static int initializePtNodeArraysCachedAddresses( |
| final ArrayList<PtNodeArray> flatNodes) { |
| int nodeArrayOffset = 0; |
| for (final PtNodeArray nodeArray : flatNodes) { |
| nodeArray.mCachedAddressBeforeUpdate = nodeArrayOffset; |
| int nodeCountSize = getPtNodeCountSize(nodeArray); |
| int nodeffset = 0; |
| for (final PtNode ptNode : nodeArray.mData) { |
| ptNode.mCachedAddressBeforeUpdate = ptNode.mCachedAddressAfterUpdate = |
| nodeCountSize + nodeArrayOffset + nodeffset; |
| nodeffset += ptNode.mCachedSize; |
| } |
| nodeArrayOffset += nodeArray.mCachedSize; |
| } |
| return nodeArrayOffset; |
| } |
| |
| /** |
| * Updates the cached addresses of node arrays after recomputing their new positions. |
| * |
| * @param flatNodes the list of node arrays. |
| */ |
| private static void updatePtNodeArraysCachedAddresses(final ArrayList<PtNodeArray> flatNodes) { |
| for (final PtNodeArray nodeArray : flatNodes) { |
| nodeArray.mCachedAddressBeforeUpdate = nodeArray.mCachedAddressAfterUpdate; |
| for (final PtNode ptNode : nodeArray.mData) { |
| ptNode.mCachedAddressBeforeUpdate = ptNode.mCachedAddressAfterUpdate; |
| } |
| } |
| } |
| |
| /** |
| * Compute the addresses and sizes of an ordered list of PtNode arrays. |
| * |
| * This method takes a list of PtNode arrays and will update their cached address and size |
| * values so that they can be written into a file. It determines the smallest size each of the |
| * PtNode arrays can be given the addresses of its children and attributes, and store that into |
| * each PtNode. |
| * The order of the PtNode is given by the order of the array. This method makes no effort |
| * to find a good order; it only mechanically computes the size this order results in. |
| * |
| * @param dict the dictionary |
| * @param flatNodes the ordered list of PtNode arrays |
| * @return the same array it was passed. The nodes have been updated for address and size. |
| */ |
| /* package */ static ArrayList<PtNodeArray> computeAddresses(final FusionDictionary dict, |
| final ArrayList<PtNodeArray> flatNodes, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| // First get the worst possible sizes and offsets |
| for (final PtNodeArray n : flatNodes) { |
| calculatePtNodeArrayMaximumSize(n, codePointToOneByteCodeMap); |
| } |
| final int offset = initializePtNodeArraysCachedAddresses(flatNodes); |
| |
| MakedictLog.i("Compressing the array addresses. Original size : " + offset); |
| MakedictLog.i("(Recursively seen size : " + offset + ")"); |
| |
| int passes = 0; |
| boolean changesDone = false; |
| do { |
| changesDone = false; |
| int ptNodeArrayStartOffset = 0; |
| for (final PtNodeArray ptNodeArray : flatNodes) { |
| ptNodeArray.mCachedAddressAfterUpdate = ptNodeArrayStartOffset; |
| final int oldNodeArraySize = ptNodeArray.mCachedSize; |
| final boolean changed = computeActualPtNodeArraySize(ptNodeArray, dict, |
| codePointToOneByteCodeMap); |
| final int newNodeArraySize = ptNodeArray.mCachedSize; |
| if (oldNodeArraySize < newNodeArraySize) { |
| throw new RuntimeException("Increased size ?!"); |
| } |
| ptNodeArrayStartOffset += newNodeArraySize; |
| changesDone |= changed; |
| } |
| updatePtNodeArraysCachedAddresses(flatNodes); |
| ++passes; |
| if (passes > MAX_PASSES) throw new RuntimeException("Too many passes - probably a bug"); |
| } while (changesDone); |
| |
| final PtNodeArray lastPtNodeArray = flatNodes.get(flatNodes.size() - 1); |
| MakedictLog.i("Compression complete in " + passes + " passes."); |
| MakedictLog.i("After address compression : " |
| + (lastPtNodeArray.mCachedAddressAfterUpdate + lastPtNodeArray.mCachedSize)); |
| |
| return flatNodes; |
| } |
| |
| /** |
| * Validity-checking method. |
| * |
| * This method checks a list of PtNode arrays for juxtaposition, that is, it will do |
| * nothing if each node array's cached address is actually the previous node array's address |
| * plus the previous node's size. |
| * If this is not the case, it will throw an exception. |
| * |
| * @param arrays the list of node arrays to check |
| */ |
| /* package */ static void checkFlatPtNodeArrayList(final ArrayList<PtNodeArray> arrays) { |
| int offset = 0; |
| int index = 0; |
| for (final PtNodeArray ptNodeArray : arrays) { |
| // BeforeUpdate and AfterUpdate addresses are the same here, so it does not matter |
| // which we use. |
| if (ptNodeArray.mCachedAddressAfterUpdate != offset) { |
| throw new RuntimeException("Wrong address for node " + index |
| + " : expected " + offset + ", got " + |
| ptNodeArray.mCachedAddressAfterUpdate); |
| } |
| ++index; |
| offset += ptNodeArray.mCachedSize; |
| } |
| } |
| |
| /** |
| * Helper method to write a children position to a file. |
| * |
| * @param buffer the buffer to write to. |
| * @param fromIndex the index in the buffer to write the address to. |
| * @param position the position to write. |
| * @return the size in bytes the address actually took. |
| */ |
| /* package */ static int writeChildrenPosition(final byte[] buffer, final int fromIndex, |
| final int position) { |
| int index = fromIndex; |
| switch (getByteSize(position)) { |
| case 1: |
| buffer[index++] = (byte)position; |
| return 1; |
| case 2: |
| buffer[index++] = (byte)(0xFF & (position >> 8)); |
| buffer[index++] = (byte)(0xFF & position); |
| return 2; |
| case 3: |
| buffer[index++] = (byte)(0xFF & (position >> 16)); |
| buffer[index++] = (byte)(0xFF & (position >> 8)); |
| buffer[index++] = (byte)(0xFF & position); |
| return 3; |
| case 0: |
| return 0; |
| default: |
| throw new RuntimeException("Position " + position + " has a strange size"); |
| } |
| } |
| |
| /** |
| * Makes the flag value for a PtNode. |
| * |
| * @param hasMultipleChars whether the PtNode has multiple chars. |
| * @param isTerminal whether the PtNode is terminal. |
| * @param childrenAddressSize the size of a children address. |
| * @param hasBigrams whether the PtNode has bigrams. |
| * @param isNotAWord whether the PtNode is not a word. |
| * @param isPossiblyOffensive whether the PtNode is a possibly offensive entry. |
| * @return the flags |
| */ |
| static int makePtNodeFlags(final boolean hasMultipleChars, final boolean isTerminal, |
| final int childrenAddressSize, final boolean hasBigrams, |
| final boolean isNotAWord, final boolean isPossiblyOffensive) { |
| byte flags = 0; |
| if (hasMultipleChars) flags |= FormatSpec.FLAG_HAS_MULTIPLE_CHARS; |
| if (isTerminal) flags |= FormatSpec.FLAG_IS_TERMINAL; |
| switch (childrenAddressSize) { |
| case 1: |
| flags |= FormatSpec.FLAG_CHILDREN_ADDRESS_TYPE_ONEBYTE; |
| break; |
| case 2: |
| flags |= FormatSpec.FLAG_CHILDREN_ADDRESS_TYPE_TWOBYTES; |
| break; |
| case 3: |
| flags |= FormatSpec.FLAG_CHILDREN_ADDRESS_TYPE_THREEBYTES; |
| break; |
| case 0: |
| flags |= FormatSpec.FLAG_CHILDREN_ADDRESS_TYPE_NOADDRESS; |
| break; |
| default: |
| throw new RuntimeException("Node with a strange address"); |
| } |
| if (hasBigrams) flags |= FormatSpec.FLAG_HAS_BIGRAMS; |
| if (isNotAWord) flags |= FormatSpec.FLAG_IS_NOT_A_WORD; |
| if (isPossiblyOffensive) flags |= FormatSpec.FLAG_IS_POSSIBLY_OFFENSIVE; |
| return flags; |
| } |
| |
| /* package */ static byte makePtNodeFlags(final PtNode node, final int childrenOffset) { |
| return (byte) makePtNodeFlags(node.mChars.length > 1, node.isTerminal(), |
| getByteSize(childrenOffset), |
| node.mBigrams != null && !node.mBigrams.isEmpty(), |
| node.mIsNotAWord, node.mIsPossiblyOffensive); |
| } |
| |
| /** |
| * Makes the flag value for a bigram. |
| * |
| * @param more whether there are more bigrams after this one. |
| * @param offset the offset of the bigram. |
| * @param bigramFrequency the frequency of the bigram, 0..255. |
| * @param unigramFrequency the unigram frequency of the same word, 0..255. |
| * @param word the second bigram, for debugging purposes |
| * @return the flags |
| */ |
| /* package */ static int makeBigramFlags(final boolean more, final int offset, |
| final int bigramFrequency, final int unigramFrequency, final String word) { |
| int bigramFlags = (more ? FormatSpec.FLAG_BIGRAM_SHORTCUT_ATTR_HAS_NEXT : 0) |
| + (offset < 0 ? FormatSpec.FLAG_BIGRAM_ATTR_OFFSET_NEGATIVE : 0); |
| switch (getByteSize(offset)) { |
| case 1: |
| bigramFlags |= FormatSpec.FLAG_BIGRAM_ATTR_ADDRESS_TYPE_ONEBYTE; |
| break; |
| case 2: |
| bigramFlags |= FormatSpec.FLAG_BIGRAM_ATTR_ADDRESS_TYPE_TWOBYTES; |
| break; |
| case 3: |
| bigramFlags |= FormatSpec.FLAG_BIGRAM_ATTR_ADDRESS_TYPE_THREEBYTES; |
| break; |
| default: |
| throw new RuntimeException("Strange offset size"); |
| } |
| final int frequency; |
| if (unigramFrequency > bigramFrequency) { |
| MakedictLog.e("Unigram freq is superior to bigram freq for \"" + word |
| + "\". Bigram freq is " + bigramFrequency + ", unigram freq for " |
| + word + " is " + unigramFrequency); |
| frequency = unigramFrequency; |
| } else { |
| frequency = bigramFrequency; |
| } |
| bigramFlags += getBigramFrequencyDiff(unigramFrequency, frequency) |
| & FormatSpec.FLAG_BIGRAM_SHORTCUT_ATTR_FREQUENCY; |
| return bigramFlags; |
| } |
| |
| public static int getBigramFrequencyDiff(final int unigramFrequency, |
| final int bigramFrequency) { |
| // We compute the difference between 255 (which means probability = 1) and the |
| // unigram score. We split this into a number of discrete steps. |
| // Now, the steps are numbered 0~15; 0 represents an increase of 1 step while 15 |
| // represents an increase of 16 steps: a value of 15 will be interpreted as the median |
| // value of the 16th step. In all justice, if the bigram frequency is low enough to be |
| // rounded below the first step (which means it is less than half a step higher than the |
| // unigram frequency) then the unigram frequency itself is the best approximation of the |
| // bigram freq that we could possibly supply, hence we should *not* include this bigram |
| // in the file at all. |
| // until this is done, we'll write 0 and slightly overestimate this case. |
| // In other words, 0 means "between 0.5 step and 1.5 step", 1 means "between 1.5 step |
| // and 2.5 steps", and 15 means "between 15.5 steps and 16.5 steps". So we want to |
| // divide our range [unigramFreq..MAX_TERMINAL_FREQUENCY] in 16.5 steps to get the |
| // step size. Then we compute the start of the first step (the one where value 0 starts) |
| // by adding half-a-step to the unigramFrequency. From there, we compute the integer |
| // number of steps to the bigramFrequency. One last thing: we want our steps to include |
| // their lower bound and exclude their higher bound so we need to have the first step |
| // start at exactly 1 unit higher than floor(unigramFreq + half a step). |
| // Note : to reconstruct the score, the dictionary reader will need to divide |
| // MAX_TERMINAL_FREQUENCY - unigramFreq by 16.5 likewise to get the value of the step, |
| // and add (discretizedFrequency + 0.5 + 0.5) times this value to get the best |
| // approximation. (0.5 to get the first step start, and 0.5 to get the middle of the |
| // step pointed by the discretized frequency. |
| final float stepSize = |
| (FormatSpec.MAX_TERMINAL_FREQUENCY - unigramFrequency) |
| / (1.5f + FormatSpec.MAX_BIGRAM_FREQUENCY); |
| final float firstStepStart = 1 + unigramFrequency + (stepSize / 2.0f); |
| final int discretizedFrequency = (int)((bigramFrequency - firstStepStart) / stepSize); |
| // If the bigram freq is less than half-a-step higher than the unigram freq, we get -1 |
| // here. The best approximation would be the unigram freq itself, so we should not |
| // include this bigram in the dictionary. For now, register as 0, and live with the |
| // small over-estimation that we get in this case. TODO: actually remove this bigram |
| // if discretizedFrequency < 0. |
| return discretizedFrequency > 0 ? discretizedFrequency : 0; |
| } |
| |
| /* package */ static int getChildrenPosition(final PtNode ptNode, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| int positionOfChildrenPosField = ptNode.mCachedAddressAfterUpdate |
| + getNodeHeaderSize(ptNode, codePointToOneByteCodeMap); |
| if (ptNode.isTerminal()) { |
| // A terminal node has the frequency. |
| // If positionOfChildrenPosField is incorrect, we may crash when jumping to the children |
| // position. |
| positionOfChildrenPosField += FormatSpec.PTNODE_FREQUENCY_SIZE; |
| } |
| return null == ptNode.mChildren ? FormatSpec.NO_CHILDREN_ADDRESS |
| : ptNode.mChildren.mCachedAddressAfterUpdate - positionOfChildrenPosField; |
| } |
| |
| /** |
| * Write a PtNodeArray. The PtNodeArray is expected to have its final position cached. |
| * |
| * @param dict the dictionary the node array is a part of (for relative offsets). |
| * @param dictEncoder the dictionary encoder. |
| * @param ptNodeArray the node array to write. |
| * @param codePointToOneByteCodeMap the map to convert the code points. |
| */ |
| /* package */ static void writePlacedPtNodeArray(final FusionDictionary dict, |
| final DictEncoder dictEncoder, final PtNodeArray ptNodeArray, |
| final HashMap<Integer, Integer> codePointToOneByteCodeMap) { |
| // TODO: Make the code in common with BinaryDictIOUtils#writePtNode |
| dictEncoder.setPosition(ptNodeArray.mCachedAddressAfterUpdate); |
| |
| final int ptNodeCount = ptNodeArray.mData.size(); |
| dictEncoder.writePtNodeCount(ptNodeCount); |
| for (int i = 0; i < ptNodeCount; ++i) { |
| final PtNode ptNode = ptNodeArray.mData.get(i); |
| if (dictEncoder.getPosition() != ptNode.mCachedAddressAfterUpdate) { |
| throw new RuntimeException("Bug: write index is not the same as the cached address " |
| + "of the node : " + dictEncoder.getPosition() + " <> " |
| + ptNode.mCachedAddressAfterUpdate); |
| } |
| // Validity checks. |
| if (DBG && ptNode.getProbability() > FormatSpec.MAX_TERMINAL_FREQUENCY) { |
| throw new RuntimeException("A node has a frequency > " |
| + FormatSpec.MAX_TERMINAL_FREQUENCY |
| + " : " + ptNode.mProbabilityInfo.toString()); |
| } |
| dictEncoder.writePtNode(ptNode, dict, codePointToOneByteCodeMap); |
| } |
| if (dictEncoder.getPosition() != ptNodeArray.mCachedAddressAfterUpdate |
| + ptNodeArray.mCachedSize) { |
| throw new RuntimeException("Not the same size : written " |
| + (dictEncoder.getPosition() - ptNodeArray.mCachedAddressAfterUpdate) |
| + " bytes from a node that should have " + ptNodeArray.mCachedSize + " bytes"); |
| } |
| } |
| |
| /** |
| * Dumps a collection of useful statistics about a list of PtNode arrays. |
| * |
| * This prints purely informative stuff, like the total estimated file size, the |
| * number of PtNode arrays, of PtNodes, the repartition of each address size, etc |
| * |
| * @param ptNodeArrays the list of PtNode arrays. |
| */ |
| /* package */ static void showStatistics(ArrayList<PtNodeArray> ptNodeArrays) { |
| int firstTerminalAddress = Integer.MAX_VALUE; |
| int lastTerminalAddress = Integer.MIN_VALUE; |
| int size = 0; |
| int ptNodes = 0; |
| int maxNodes = 0; |
| int maxRuns = 0; |
| for (final PtNodeArray ptNodeArray : ptNodeArrays) { |
| if (maxNodes < ptNodeArray.mData.size()) maxNodes = ptNodeArray.mData.size(); |
| for (final PtNode ptNode : ptNodeArray.mData) { |
| ++ptNodes; |
| if (ptNode.mChars.length > maxRuns) maxRuns = ptNode.mChars.length; |
| if (ptNode.isTerminal()) { |
| if (ptNodeArray.mCachedAddressAfterUpdate < firstTerminalAddress) |
| firstTerminalAddress = ptNodeArray.mCachedAddressAfterUpdate; |
| if (ptNodeArray.mCachedAddressAfterUpdate > lastTerminalAddress) |
| lastTerminalAddress = ptNodeArray.mCachedAddressAfterUpdate; |
| } |
| } |
| if (ptNodeArray.mCachedAddressAfterUpdate + ptNodeArray.mCachedSize > size) { |
| size = ptNodeArray.mCachedAddressAfterUpdate + ptNodeArray.mCachedSize; |
| } |
| } |
| final int[] ptNodeCounts = new int[maxNodes + 1]; |
| final int[] runCounts = new int[maxRuns + 1]; |
| for (final PtNodeArray ptNodeArray : ptNodeArrays) { |
| ++ptNodeCounts[ptNodeArray.mData.size()]; |
| for (final PtNode ptNode : ptNodeArray.mData) { |
| ++runCounts[ptNode.mChars.length]; |
| } |
| } |
| |
| MakedictLog.i("Statistics:\n" |
| + " Total file size " + size + "\n" |
| + " " + ptNodeArrays.size() + " node arrays\n" |
| + " " + ptNodes + " PtNodes (" + ((float)ptNodes / ptNodeArrays.size()) |
| + " PtNodes per node)\n" |
| + " First terminal at " + firstTerminalAddress + "\n" |
| + " Last terminal at " + lastTerminalAddress + "\n" |
| + " PtNode stats : max = " + maxNodes); |
| } |
| |
| /** |
| * Writes a file header to an output stream. |
| * |
| * @param destination the stream to write the file header to. |
| * @param dict the dictionary to write. |
| * @param formatOptions file format options. |
| * @param codePointOccurrenceArray code points ordered by occurrence count. |
| * @return the size of the header. |
| */ |
| /* package */ static int writeDictionaryHeader(final OutputStream destination, |
| final FusionDictionary dict, final FormatOptions formatOptions, |
| final ArrayList<Entry<Integer, Integer>> codePointOccurrenceArray) |
| throws IOException, UnsupportedFormatException { |
| final int version = formatOptions.mVersion; |
| if ((version >= FormatSpec.MINIMUM_SUPPORTED_STATIC_VERSION && |
| version <= FormatSpec.MAXIMUM_SUPPORTED_STATIC_VERSION) || ( |
| version >= FormatSpec.MINIMUM_SUPPORTED_DYNAMIC_VERSION && |
| version <= FormatSpec.MAXIMUM_SUPPORTED_DYNAMIC_VERSION)) { |
| // Dictionary is valid |
| } else { |
| throw new UnsupportedFormatException("Requested file format version " + version |
| + ", but this implementation only supports static versions " |
| + FormatSpec.MINIMUM_SUPPORTED_STATIC_VERSION + " through " |
| + FormatSpec.MAXIMUM_SUPPORTED_STATIC_VERSION + " and dynamic versions " |
| + FormatSpec.MINIMUM_SUPPORTED_DYNAMIC_VERSION + " through " |
| + FormatSpec.MAXIMUM_SUPPORTED_DYNAMIC_VERSION); |
| } |
| |
| ByteArrayOutputStream headerBuffer = new ByteArrayOutputStream(256); |
| |
| // The magic number in big-endian order. |
| // Magic number for all versions. |
| headerBuffer.write((byte) (0xFF & (FormatSpec.MAGIC_NUMBER >> 24))); |
| headerBuffer.write((byte) (0xFF & (FormatSpec.MAGIC_NUMBER >> 16))); |
| headerBuffer.write((byte) (0xFF & (FormatSpec.MAGIC_NUMBER >> 8))); |
| headerBuffer.write((byte) (0xFF & FormatSpec.MAGIC_NUMBER)); |
| // Dictionary version. |
| headerBuffer.write((byte) (0xFF & (version >> 8))); |
| headerBuffer.write((byte) (0xFF & version)); |
| |
| // Options flags |
| // TODO: Remove this field. |
| final int options = 0; |
| headerBuffer.write((byte) (0xFF & (options >> 8))); |
| headerBuffer.write((byte) (0xFF & options)); |
| final int headerSizeOffset = headerBuffer.size(); |
| // Placeholder to be written later with header size. |
| for (int i = 0; i < 4; ++i) { |
| headerBuffer.write(0); |
| } |
| // Write out the options. |
| for (final String key : dict.mOptions.mAttributes.keySet()) { |
| final String value = dict.mOptions.mAttributes.get(key); |
| CharEncoding.writeString(headerBuffer, key, null); |
| CharEncoding.writeString(headerBuffer, value, null); |
| } |
| // Write out the codePointTable if there is codePointOccurrenceArray. |
| if (codePointOccurrenceArray != null) { |
| final String codePointTableString = |
| encodeCodePointTable(codePointOccurrenceArray); |
| CharEncoding.writeString(headerBuffer, DictionaryHeader.CODE_POINT_TABLE_KEY, null); |
| CharEncoding.writeString(headerBuffer, codePointTableString, null); |
| } |
| final int size = headerBuffer.size(); |
| final byte[] bytes = headerBuffer.toByteArray(); |
| // Write out the header size. |
| bytes[headerSizeOffset] = (byte) (0xFF & (size >> 24)); |
| bytes[headerSizeOffset + 1] = (byte) (0xFF & (size >> 16)); |
| bytes[headerSizeOffset + 2] = (byte) (0xFF & (size >> 8)); |
| bytes[headerSizeOffset + 3] = (byte) (0xFF & (size >> 0)); |
| destination.write(bytes); |
| |
| headerBuffer.close(); |
| return size; |
| } |
| |
| static final class CodePointTable { |
| final HashMap<Integer, Integer> mCodePointToOneByteCodeMap; |
| final ArrayList<Entry<Integer, Integer>> mCodePointOccurrenceArray; |
| |
| // Let code point table empty for version 200 dictionary which used in test |
| CodePointTable() { |
| mCodePointToOneByteCodeMap = null; |
| mCodePointOccurrenceArray = null; |
| } |
| |
| CodePointTable(final HashMap<Integer, Integer> codePointToOneByteCodeMap, |
| final ArrayList<Entry<Integer, Integer>> codePointOccurrenceArray) { |
| mCodePointToOneByteCodeMap = codePointToOneByteCodeMap; |
| mCodePointOccurrenceArray = codePointOccurrenceArray; |
| } |
| } |
| |
| private static String encodeCodePointTable( |
| final ArrayList<Entry<Integer, Integer>> codePointOccurrenceArray) { |
| final StringBuilder codePointTableString = new StringBuilder(); |
| int currentCodePointTableIndex = FormatSpec.MINIMAL_ONE_BYTE_CHARACTER_VALUE; |
| for (final Entry<Integer, Integer> entry : codePointOccurrenceArray) { |
| // Native reads the table as a string |
| codePointTableString.appendCodePoint(entry.getKey()); |
| if (FormatSpec.MAXIMAL_ONE_BYTE_CHARACTER_VALUE < ++currentCodePointTableIndex) { |
| break; |
| } |
| } |
| return codePointTableString.toString(); |
| } |
| } |