Merge "Add FusionDictionaryBufferInterface." into jb-mr1-dev

main
Ken Wakasa 2012-08-29 18:49:02 -07:00 committed by Android (Google) Code Review
commit d2a81ab9bd
1 changed files with 107 additions and 68 deletions

View File

@ -188,6 +188,54 @@ public class BinaryDictInputOutput {
// suspicion that a bug might be causing an infinite loop.
private static final int MAX_PASSES = 24;
private interface FusionDictionaryBufferInterface {
public int readUnsignedByte();
public int readUnsignedShort();
public int readUnsignedInt24();
public int readInt();
public int position();
public void position(int newPosition);
}
private static final class ByteBufferWrapper implements FusionDictionaryBufferInterface {
private ByteBuffer buffer;
ByteBufferWrapper(final ByteBuffer buffer) {
this.buffer = buffer;
}
@Override
public int readUnsignedByte() {
return ((int)buffer.get()) & 0xFF;
}
@Override
public int readUnsignedShort() {
return ((int)buffer.getShort()) & 0xFFFF;
}
@Override
public int readUnsignedInt24() {
final int retval = readUnsignedByte();
return (retval << 16) + readUnsignedShort();
}
@Override
public int readInt() {
return buffer.getInt();
}
@Override
public int position() {
return buffer.position();
}
@Override
public void position(int newPos) {
buffer.position(newPos);
return;
}
}
/**
* A class grouping utility function for our specific character encoding.
*/
@ -310,9 +358,9 @@ public class BinaryDictInputOutput {
}
/**
* Reads a string from a ByteBuffer. This is the converse of the above method.
* Reads a string from a buffer. This is the converse of the above method.
*/
private static String readString(final ByteBuffer buffer) {
private static String readString(final FusionDictionaryBufferInterface buffer) {
final StringBuilder s = new StringBuilder();
int character = readChar(buffer);
while (character != INVALID_CHARACTER) {
@ -323,19 +371,19 @@ public class BinaryDictInputOutput {
}
/**
* Reads a character from the ByteBuffer.
* Reads a character from the buffer.
*
* This follows the character format documented earlier in this source file.
*
* @param buffer the buffer, positioned over an encoded character.
* @return the character code.
*/
private static int readChar(final ByteBuffer buffer) {
int character = readUnsignedByte(buffer);
private static int readChar(final FusionDictionaryBufferInterface buffer) {
int character = buffer.readUnsignedByte();
if (!fitsOnOneByte(character)) {
if (GROUP_CHARACTERS_TERMINATOR == character) return INVALID_CHARACTER;
character <<= 16;
character += readUnsignedShort(buffer);
character += buffer.readUnsignedShort();
}
return character;
}
@ -1093,10 +1141,10 @@ public class BinaryDictInputOutput {
// readDictionaryBinary is the public entry point for them.
static final int[] characterBuffer = new int[MAX_WORD_LENGTH];
private static CharGroupInfo readCharGroup(final ByteBuffer buffer,
private static CharGroupInfo readCharGroup(final FusionDictionaryBufferInterface buffer,
final int originalGroupAddress) {
int addressPointer = originalGroupAddress;
final int flags = readUnsignedByte(buffer);
final int flags = buffer.readUnsignedByte();
++addressPointer;
final int characters[];
if (0 != (flags & FLAG_HAS_MULTIPLE_CHARS)) {
@ -1117,22 +1165,22 @@ public class BinaryDictInputOutput {
final int frequency;
if (0 != (FLAG_IS_TERMINAL & flags)) {
++addressPointer;
frequency = readUnsignedByte(buffer);
frequency = buffer.readUnsignedByte();
} else {
frequency = CharGroup.NOT_A_TERMINAL;
}
int childrenAddress = addressPointer;
switch (flags & MASK_GROUP_ADDRESS_TYPE) {
case FLAG_GROUP_ADDRESS_TYPE_ONEBYTE:
childrenAddress += readUnsignedByte(buffer);
childrenAddress += buffer.readUnsignedByte();
addressPointer += 1;
break;
case FLAG_GROUP_ADDRESS_TYPE_TWOBYTES:
childrenAddress += readUnsignedShort(buffer);
childrenAddress += buffer.readUnsignedShort();
addressPointer += 2;
break;
case FLAG_GROUP_ADDRESS_TYPE_THREEBYTES:
childrenAddress += readUnsignedInt24(buffer);
childrenAddress += buffer.readUnsignedInt24();
addressPointer += 3;
break;
case FLAG_GROUP_ADDRESS_TYPE_NOADDRESS:
@ -1144,9 +1192,9 @@ public class BinaryDictInputOutput {
if (0 != (flags & FLAG_HAS_SHORTCUT_TARGETS)) {
final int pointerBefore = buffer.position();
shortcutTargets = new ArrayList<WeightedString>();
buffer.getShort(); // Skip the size
buffer.readUnsignedShort(); // Skip the size
while (true) {
final int targetFlags = readUnsignedByte(buffer);
final int targetFlags = buffer.readUnsignedByte();
final String word = CharEncoding.readString(buffer);
shortcutTargets.add(new WeightedString(word,
targetFlags & FLAG_ATTRIBUTE_FREQUENCY));
@ -1158,22 +1206,22 @@ public class BinaryDictInputOutput {
if (0 != (flags & FLAG_HAS_BIGRAMS)) {
bigrams = new ArrayList<PendingAttribute>();
while (true) {
final int bigramFlags = readUnsignedByte(buffer);
final int bigramFlags = buffer.readUnsignedByte();
++addressPointer;
final int sign = 0 == (bigramFlags & FLAG_ATTRIBUTE_OFFSET_NEGATIVE) ? 1 : -1;
int bigramAddress = addressPointer;
switch (bigramFlags & MASK_ATTRIBUTE_ADDRESS_TYPE) {
case FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE:
bigramAddress += sign * readUnsignedByte(buffer);
bigramAddress += sign * buffer.readUnsignedByte();
addressPointer += 1;
break;
case FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES:
bigramAddress += sign * readUnsignedShort(buffer);
bigramAddress += sign * buffer.readUnsignedShort();
addressPointer += 2;
break;
case FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES:
final int offset = (readUnsignedByte(buffer) << 16)
+ readUnsignedShort(buffer);
final int offset = (buffer.readUnsignedByte() << 16)
+ buffer.readUnsignedShort();
bigramAddress += sign * offset;
addressPointer += 3;
break;
@ -1192,13 +1240,13 @@ public class BinaryDictInputOutput {
/**
* Reads and returns the char group count out of a buffer and forwards the pointer.
*/
private static int readCharGroupCount(final ByteBuffer buffer) {
final int msb = readUnsignedByte(buffer);
private static int readCharGroupCount(final FusionDictionaryBufferInterface buffer) {
final int msb = buffer.readUnsignedByte();
if (MAX_CHARGROUPS_FOR_ONE_BYTE_CHARGROUP_COUNT >= msb) {
return msb;
} else {
return ((MAX_CHARGROUPS_FOR_ONE_BYTE_CHARGROUP_COUNT & msb) << 8)
+ readUnsignedByte(buffer);
+ buffer.readUnsignedByte();
}
}
@ -1215,8 +1263,8 @@ public class BinaryDictInputOutput {
* @param address the address to seek.
* @return the word, as a string.
*/
private static String getWordAtAddress(final ByteBuffer buffer, final int headerSize,
final int address) {
private static String getWordAtAddress(final FusionDictionaryBufferInterface buffer,
final int headerSize, final int address) {
final String cachedString = wordCache.get(address);
if (null != cachedString) return cachedString;
final int originalPointer = buffer.position();
@ -1241,7 +1289,7 @@ public class BinaryDictInputOutput {
builder.append(new String(last.mCharacters, 0, last.mCharacters.length));
buffer.position(last.mChildrenAddress + headerSize);
groupOffset = last.mChildrenAddress + 1;
i = readUnsignedByte(buffer);
i = buffer.readUnsignedByte();
last = null;
continue;
}
@ -1251,7 +1299,7 @@ public class BinaryDictInputOutput {
builder.append(new String(last.mCharacters, 0, last.mCharacters.length));
buffer.position(last.mChildrenAddress + headerSize);
groupOffset = last.mChildrenAddress + 1;
i = readUnsignedByte(buffer);
i = buffer.readUnsignedByte();
last = null;
continue;
}
@ -1262,10 +1310,10 @@ public class BinaryDictInputOutput {
}
/**
* Reads a single node from a binary file.
* Reads a single node from a buffer.
*
* This methods reads the file at the current position of its file pointer. A node is
* fully expected to start at the current position.
* This methods reads the file at the current position. A node is fully expected to start at
* the current position.
* This will recursively read other nodes into the structure, populating the reverse
* maps on the fly and using them to keep track of already read nodes.
*
@ -1275,7 +1323,7 @@ public class BinaryDictInputOutput {
* @param reverseGroupMap a mapping from addresses to already read character groups.
* @return the read node with all his children already read.
*/
private static Node readNode(final ByteBuffer buffer, final int headerSize,
private static Node readNode(final FusionDictionaryBufferInterface buffer, final int headerSize,
final Map<Integer, Node> reverseNodeMap, final Map<Integer, CharGroup> reverseGroupMap)
throws IOException {
final int nodeOrigin = buffer.position() - headerSize;
@ -1283,7 +1331,7 @@ public class BinaryDictInputOutput {
final ArrayList<CharGroup> nodeContents = new ArrayList<CharGroup>();
int groupOffset = nodeOrigin + getGroupCountSize(count);
for (int i = count; i > 0; --i) {
CharGroupInfo info =readCharGroup(buffer, groupOffset);
CharGroupInfo info = readCharGroup(buffer, groupOffset);
ArrayList<WeightedString> shortcutTargets = info.mShortcutTargets;
ArrayList<WeightedString> bigrams = null;
if (null != info.mBigrams) {
@ -1323,42 +1371,49 @@ public class BinaryDictInputOutput {
* Helper function to get the binary format version from the header.
* @throws IOException
*/
private static int getFormatVersion(final ByteBuffer buffer) throws IOException {
final int magic_v1 = readUnsignedShort(buffer);
if (VERSION_1_MAGIC_NUMBER == magic_v1) return readUnsignedByte(buffer);
final int magic_v2 = (magic_v1 << 16) + readUnsignedShort(buffer);
if (VERSION_2_MAGIC_NUMBER == magic_v2) return readUnsignedShort(buffer);
private static int getFormatVersion(final FusionDictionaryBufferInterface buffer)
throws IOException {
final int magic_v1 = buffer.readUnsignedShort();
if (VERSION_1_MAGIC_NUMBER == magic_v1) return buffer.readUnsignedByte();
final int magic_v2 = (magic_v1 << 16) + buffer.readUnsignedShort();
if (VERSION_2_MAGIC_NUMBER == magic_v2) return buffer.readUnsignedShort();
return NOT_A_VERSION_NUMBER;
}
/**
* Reads options from a file and populate a map with their contents.
* Reads options from a buffer and populate a map with their contents.
*
* The file is read at the current file pointer, so the caller must take care the pointer
* The buffer is read at the current position, so the caller must take care the pointer
* is in the right place before calling this.
*/
public static void populateOptions(final ByteBuffer buffer, final int headerSize,
final HashMap<String, String> options) {
public static void populateOptions(final FusionDictionaryBufferInterface buffer,
final int headerSize, final HashMap<String, String> options) {
while (buffer.position() < headerSize) {
final String key = CharEncoding.readString(buffer);
final String value = CharEncoding.readString(buffer);
options.put(key, value);
}
}
// TODO: remove this method.
public static void populateOptions(final ByteBuffer buffer, final int headerSize,
final HashMap<String, String> options) {
populateOptions(new ByteBufferWrapper(buffer), headerSize, options);
}
/**
* Reads a byte buffer and returns the memory representation of the dictionary.
* Reads a buffer and returns the memory representation of the dictionary.
*
* This high-level method takes a binary file and reads its contents, populating a
* This high-level method takes a buffer and reads its contents, populating a
* FusionDictionary structure. The optional dict argument is an existing dictionary to
* which words from the file should be added. If it is null, a new dictionary is created.
* which words from the buffer should be added. If it is null, a new dictionary is created.
*
* @param buffer the buffer to read.
* @param dict an optional dictionary to add words to, or null.
* @return the created (or merged) dictionary.
*/
public static FusionDictionary readDictionaryBinary(final ByteBuffer buffer,
final FusionDictionary dict) throws IOException, UnsupportedFormatException {
public static FusionDictionary readDictionaryBinary(
final FusionDictionaryBufferInterface buffer, final FusionDictionary dict)
throws IOException, UnsupportedFormatException {
// Check file version
final int version = getFormatVersion(buffer);
if (version < MINIMUM_SUPPORTED_VERSION || version > MAXIMUM_SUPPORTED_VERSION) {
@ -1371,14 +1426,14 @@ public class BinaryDictInputOutput {
wordCache.clear();
// Read options
final int optionsFlags = readUnsignedShort(buffer);
final int optionsFlags = buffer.readUnsignedShort();
final int headerSize;
final HashMap<String, String> options = new HashMap<String, String>();
if (version < FIRST_VERSION_WITH_HEADER_SIZE) {
headerSize = buffer.position();
} else {
headerSize = buffer.getInt();
headerSize = buffer.readInt();
populateOptions(buffer, headerSize, options);
buffer.position(headerSize);
}
@ -1413,26 +1468,10 @@ public class BinaryDictInputOutput {
return newDict;
}
/**
* Helper function to read one byte from ByteBuffer.
*/
private static int readUnsignedByte(final ByteBuffer buffer) {
return ((int)buffer.get()) & 0xFF;
}
/**
* Helper function to read two byte from ByteBuffer.
*/
private static int readUnsignedShort(final ByteBuffer buffer) {
return ((int)buffer.getShort()) & 0xFFFF;
}
/**
* Helper function to read three byte from ByteBuffer.
*/
private static int readUnsignedInt24(final ByteBuffer buffer) {
final int value = readUnsignedByte(buffer) << 16;
return value + readUnsignedShort(buffer);
// TODO: remove this method.
public static FusionDictionary readDictionaryBinary(final ByteBuffer buffer,
final FusionDictionary dict) throws IOException, UnsupportedFormatException {
return readDictionaryBinary(new ByteBufferWrapper(buffer), dict);
}
/**
@ -1450,7 +1489,7 @@ public class BinaryDictInputOutput {
inStream = new FileInputStream(file);
final ByteBuffer buffer = inStream.getChannel().map(
FileChannel.MapMode.READ_ONLY, 0, file.length());
final int version = getFormatVersion(buffer);
final int version = getFormatVersion(new ByteBufferWrapper(buffer));
return (version >= MINIMUM_SUPPORTED_VERSION && version <= MAXIMUM_SUPPORTED_VERSION);
} catch (FileNotFoundException e) {
return false;