Hi Andrzej,
I have fixed the decodeIntegerIndexOnSecondBit() in following manner (note that this is C# code):
/*
* C.25
*/
protected int decodeIntegerIndexOnSecondBit()
{
int b = read() | 0x80;
switch (DecoderStateTables.ISTRING[b])
{
case DecoderStateTables.ISTRING_INDEX_SMALL:
return b & EncodingConstants.INTEGER_2ND_BIT_SMALL_MASK;
case DecoderStateTables.ISTRING_INDEX_MEDIUM:
return (((b & EncodingConstants.INTEGER_2ND_BIT_MEDIUM_MASK) << 8) | read()) + EncodingConstants.INTEGER_2ND_BIT_SMALL_LIMIT;
case DecoderStateTables.ISTRING_INDEX_LARGE:
return (((b & EncodingConstants.INTEGER_2ND_BIT_LARGE_MASK) << 16) | (read() << 8) | read()) + EncodingConstants.INTEGER_2ND_BIT_MEDIUM_LIMIT;
case DecoderStateTables.ISTRING_SMALL_LENGTH:
case DecoderStateTables.ISTRING_MEDIUM_LENGTH:
case DecoderStateTables.ISTRING_LARGE_LENGTH:
default:
throw new FastInfosetException(Strings.message_decodingIndexOnSecondBit);
}
}
So now I can successfully read the Initial Vocabulary encoded at the beginning of your document. But your document seems that it's ending with a single terminator right after the Initial Vocabulary encoding. So there is no root element there?
With best regards,
Arman
Andrzej Gladkowski wrote:
> On Tue, Nov 3, 2009 at 3:26 PM, Arman Djusupov <arman_at_noemax.com> wrote:
>
>> Hello Andrzej,
>>
>> It seems that the decodeNumberOfItemsOfSequence() method indeed has a
>> problem, since it doesn't add the lower boundary of the range after reading
>> the value.
>>
>> But why do you think that C.25.2 is implemented in the wrong way?
>>
>> As far as I can see C.25.2 implementation is correct. It doesn't add +1
>> when reading 1-64 value range, because in the Java implementation the
>> vocabulary tables are 0 based, so practically adding and subtracting 1 while
>> reading/writing is not necessary. The same applies to other ranges. It adds
>> 64 instead of 65 as lower boundary for medium ranged values and 8256 instead
>> of 8257 for high ranged values.
>> With best regards,
>> Arman
>>
>>
> #Yes, I agree that subtracting 1 while reading/writing is not necessary.
> # No, I think the whole C.25 is implemented correctly, it's about something
> else. Please read further comments.
>
> # I think confusion is caused by the following points:
>
> C.13.4 If the alternative string-index is present, then the bit '1'
> (discriminant) is appended to the bit stream, and
> the string-index is encoded as described in C.25
> C.16.5 If the optional component prefix-string-index is present, then the
> bit '0' (padding) is appended to the bit
> stream, and the component is encoded as described in C.25.
> C.16.6 If the optional component namespace-name-string-index is present,
> then the bit '0' (padding) is appended
> to the bit stream, and the component is encoded as described in C.25.
> C.16.7 The bit '0' (padding) is appended to the bit stream, and the
> component local-name-string-index is
> encoded as described in C.25.
>
> # The function 'decodeNumberOfItemsOfSequence(..)' implements correctly
> point *C.13.4*, when the octed starts with '1'
> # but it fails if the octet starts with '0' !
> # I have looked into Encoder.java and there are two separate encoding
> methods:
> - Encoder.encodeNonZeroIntegerOnSecondBitFirstBitZero(..)
> - Encoder.encodeNonZeroIntegerOnSecondBitFirstBitOne(..)
> # We could fix Decoder.decodeNumberOfItemsOfSequence(..) by adding another
> method to handle octets starting with '0' or simply by ignoring the first
> bit in the octet all the time.
>
> # Here is the junit test that can be used to test both scenarios (by
> uncommenting the right FIRST_BIT constant in the code):
> =========================================================================
> import java.io.IOException;
> import org.jvnet.fastinfoset.FastInfosetException;
> import com.sun.xml.fastinfoset.Decoder;
> import junit.framework.TestCase;
>
> public class DecoderTest extends TestCase {
> /* Uncomment the right section to test first bit in the octet '1' or '0'
> */
> //private static final byte FIRST_BIT = (byte)0x80;//1000 0000 // C.13.4
> private static final byte FIRST_BIT = (byte)0x00;//0000 0000 // C.16.5-7
>
> private TestDecoder decoder;
> private byte[] buffer;
> private class TestDecoder extends Decoder {
> public TestDecoder(byte[] buffer) {
> this._octetBufferOffset = 0;
> this._octetBufferEnd = 15;
> this._octetBuffer = buffer;
> }
> public int decodeIntegerIndexOnSecondBitTest() throws
> FastInfosetException, IOException {
> return decodeIntegerIndexOnSecondBit();
> }
> }
>
> protected void setUp() throws java.lang.Exception {
> buffer = new byte[16];
> decoder = new TestDecoder(buffer);
> }
> // integer in range [1, 64], ( [0, 63] ) 6 bits
> public void testIntegerIndex0() throws IOException, FastInfosetException
> {
> buffer[0] = 0x00 | FIRST_BIT;
> final int result = decoder.decodeIntegerIndexOnSecondBitTest();
>
> assertEquals(0x00, result);
> }
> // integer in range [65, 8256], ( [64, 8255] ) 13 bits
> public void testIntegerIndex321() throws IOException,
> FastInfosetException {
> buffer[0] = 0x41 | FIRST_BIT;//100 0001 - last five bits
> buffer[1] = 0x01;// 0000 0001 - eight following bits
> final int result = decoder.decodeIntegerIndexOnSecondBitTest();
>
> assertEquals(257 + 64, result);
> }
> // integer in range [8257, 1048576], ( [8256, 1048575] ) 20 bits
> public void testIntegerIndex73793() throws IOException,
> FastInfosetException {
> buffer[0] = 0x61 | FIRST_BIT;//110 0001 - last four bits
> buffer[1] = 0x00;// 0000 0000 - eight following bits
> buffer[2] = 0x01;// 0000 0001 - eight following bits
> final int result = decoder.decodeIntegerIndexOnSecondBitTest();
>
> assertEquals(65537 + 8256, result);
> }
> }
> =========================================================================
>
> # Another small issue can be found in
> Decoder.decodeTableItems(QualifiedNameArray array, boolean isAttribute).
> # Wrong:
>
> String namespaceName = "";
> int namespaceNameIndex = -1;
> if ((b & EncodingConstants.NAME_SURROGATE_NAME_FLAG) > 0) {
> namespaceNameIndex = decodeIntegerIndexOnSecondBit();
> namespaceName = *_v.prefix.get(prefixIndex);*
> }
>
> # Correct: _v.prefix.get(prefixIndex); changed to
> _v.namespaceName.get(namespaceNameIndex);
>
> String namespaceName = "";
> int namespaceNameIndex = -1;
> if ((b & EncodingConstants.NAME_SURROGATE_NAME_FLAG) > 0) {
> namespaceNameIndex = decodeIntegerIndexOnSecondBit();
> namespaceName = *_v.namespaceName.get(namespaceNameIndex);*
> }
>
>
> Cheers,
> ~Andrzej
>