Touch up the header format

Change-Id: Id2a65e8b74228eba18bbaaf3794cd0e9b7cd470d
main
Jean Chalard 2012-03-06 18:04:08 +09:00
parent 168d2c094b
commit a9a5dd07b5
1 changed files with 22 additions and 22 deletions

View File

@ -115,6 +115,7 @@ public class BinaryDictInputOutput {
private static final int VERSION_2_MAGIC_NUMBER = 0x9BC13AFE;
private static final int MINIMUM_SUPPORTED_VERSION = 1;
private static final int MAXIMUM_SUPPORTED_VERSION = 2;
private static final int NOT_A_VERSION_NUMBER = -1;
private static final int FIRST_VERSION_WITH_HEADER_SIZE = 2;
// No options yet, reserved for future use.
@ -829,24 +830,28 @@ public class BinaryDictInputOutput {
buffer[index++] = (byte) (0xFF & (VERSION_2_MAGIC_NUMBER >> 16));
buffer[index++] = (byte) (0xFF & (VERSION_2_MAGIC_NUMBER >> 8));
buffer[index++] = (byte) (0xFF & VERSION_2_MAGIC_NUMBER);
// Dictionary version.
buffer[index++] = (byte) (0xFF & (version >> 8));
buffer[index++] = (byte) (0xFF & version);
} else {
// Magic number for version 1.
buffer[index++] = (byte) (0xFF & (VERSION_1_MAGIC_NUMBER >> 8));
buffer[index++] = (byte) (0xFF & VERSION_1_MAGIC_NUMBER);
}
// Dictionary version.
buffer[index++] = (byte) (0xFF & version);
}
// Options flags
buffer[index++] = (byte) (0xFF & (OPTIONS >> 8));
buffer[index++] = (byte) (0xFF & OPTIONS);
if (version >= FIRST_VERSION_WITH_HEADER_SIZE) {
final int headerSizeOffset = index;
index += 3; // Size of the header size
index += 4; // Size of the header size
// TODO: Write out the header contents here.
// Write out the header size.
buffer[headerSizeOffset] = (byte) (0xFF & (index >> 16));
buffer[headerSizeOffset + 1] = (byte) (0xFF & (index >> 8));
buffer[headerSizeOffset + 2] = (byte) (0xFF & (index >> 0));
buffer[headerSizeOffset] = (byte) (0xFF & (index >> 24));
buffer[headerSizeOffset + 1] = (byte) (0xFF & (index >> 16));
buffer[headerSizeOffset + 2] = (byte) (0xFF & (index >> 8));
buffer[headerSizeOffset + 3] = (byte) (0xFF & (index >> 0));
}
destination.write(buffer, 0, index);
@ -1122,14 +1127,14 @@ public class BinaryDictInputOutput {
}
/**
* Helper function to test the magic number of the file.
* Helper function to get the binary format version from the header.
*/
private static boolean isExpectedMagicNumber(final RandomAccessFile source) throws IOException {
private static int getFormatVersion(final RandomAccessFile source) throws IOException {
final int magic_v1 = source.readUnsignedShort();
if (VERSION_1_MAGIC_NUMBER == magic_v1) return true;
if (VERSION_1_MAGIC_NUMBER == magic_v1) return source.readUnsignedByte();
final int magic_v2 = (magic_v1 << 16) + source.readUnsignedShort();
if (VERSION_2_MAGIC_NUMBER == magic_v2) return true;
return false;
if (VERSION_2_MAGIC_NUMBER == magic_v2) return source.readUnsignedShort();
return NOT_A_VERSION_NUMBER;
}
/**
@ -1145,15 +1150,9 @@ public class BinaryDictInputOutput {
*/
public static FusionDictionary readDictionaryBinary(final RandomAccessFile source,
final FusionDictionary dict) throws IOException, UnsupportedFormatException {
// Check magic number
if (!isExpectedMagicNumber(source)) {
throw new UnsupportedFormatException("The magic number in this file does not match "
+ "the expected value");
}
// Check file version
final int version = source.readUnsignedByte();
if (version > MAXIMUM_SUPPORTED_VERSION) {
final int version = getFormatVersion(source);
if (version < MINIMUM_SUPPORTED_VERSION || version > MAXIMUM_SUPPORTED_VERSION ) {
throw new UnsupportedFormatException("This file has version " + version
+ ", but this implementation does not support versions above "
+ MAXIMUM_SUPPORTED_VERSION);
@ -1166,8 +1165,8 @@ public class BinaryDictInputOutput {
if (version < FIRST_VERSION_WITH_HEADER_SIZE) {
headerSize = source.getFilePointer();
} else {
headerSize = (source.readUnsignedByte() << 16) + (source.readUnsignedByte() << 8)
+ source.readUnsignedByte();
headerSize = (source.readUnsignedByte() << 24) + (source.readUnsignedByte() << 16)
+ (source.readUnsignedByte() << 8) + source.readUnsignedByte();
// read the header body
source.seek(headerSize);
}
@ -1198,7 +1197,8 @@ public class BinaryDictInputOutput {
public static boolean isBinaryDictionary(final String filename) {
try {
RandomAccessFile f = new RandomAccessFile(filename, "r");
return isExpectedMagicNumber(f);
final int version = getFormatVersion(f);
return (version >= MINIMUM_SUPPORTED_VERSION && version <= MAXIMUM_SUPPORTED_VERSION);
} catch (FileNotFoundException e) {
return false;
} catch (IOException e) {