static DecoderResult decode(
byte[] bytes, Version version, ErrorCorrectionLevel ecLevel, Hashtable hints)
throws FormatException {
BitSource bits = new BitSource(bytes);
StringBuffer result = new StringBuffer(50);
CharacterSetECI currentCharacterSetECI = null;
boolean fc1InEffect = false;
Vector byteSegments = new Vector(1);
Mode mode;
do {
// While still another segment to read...
if (bits.available() < 4) {
// OK, assume we're done. Really, a TERMINATOR mode should have been recorded here
mode = Mode.TERMINATOR;
} else {
try {
mode = Mode.forBits(bits.readBits(4)); // mode is encoded by 4 bits
} catch (IllegalArgumentException iae) {
throw FormatException.getFormatInstance();
}
}
if (!mode.equals(Mode.TERMINATOR)) {
if (mode.equals(Mode.FNC1_FIRST_POSITION) || mode.equals(Mode.FNC1_SECOND_POSITION)) {
// We do little with FNC1 except alter the parsed result a bit according to the spec
fc1InEffect = true;
} else if (mode.equals(Mode.STRUCTURED_APPEND)) {
// not really supported; all we do is ignore it
// Read next 8 bits (symbol sequence #) and 8 bits (parity data), then continue
bits.readBits(16);
} else if (mode.equals(Mode.ECI)) {
// Count doesn't apply to ECI
int value = parseECIValue(bits);
currentCharacterSetECI = CharacterSetECI.getCharacterSetECIByValue(value);
if (currentCharacterSetECI == null) {
throw FormatException.getFormatInstance();
}
} else {
// First handle Hanzi mode which does not start with character count
if (mode.equals(Mode.HANZI)) {
// chinese mode contains a sub set indicator right after mode indicator
int subset = bits.readBits(4);
int countHanzi = bits.readBits(mode.getCharacterCountBits(version));
if (subset == GB2312_SUBSET) {
decodeHanziSegment(bits, result, countHanzi);
}
} else {
// "Normal" QR code modes:
// How many characters will follow, encoded in this mode?
int count = bits.readBits(mode.getCharacterCountBits(version));
if (mode.equals(Mode.NUMERIC)) {
decodeNumericSegment(bits, result, count);
} else if (mode.equals(Mode.ALPHANUMERIC)) {
decodeAlphanumericSegment(bits, result, count, fc1InEffect);
} else if (mode.equals(Mode.BYTE)) {
decodeByteSegment(bits, result, count, currentCharacterSetECI, byteSegments, hints);
} else if (mode.equals(Mode.KANJI)) {
decodeKanjiSegment(bits, result, count);
} else {
throw FormatException.getFormatInstance();
}
}
}
}
} while (!mode.equals(Mode.TERMINATOR));
return new DecoderResult(
bytes,
result.toString(),
byteSegments.isEmpty() ? null : byteSegments,
ecLevel == null ? null : ecLevel.toString());
}
