@Override
protected IScalarEvaluator createEvaluator(IHyracksTaskContext ctx, IScalarEvaluator[] args)
throws AlgebricksException {
final ArrayBackedValueStorage abvs = new ArrayBackedValueStorage();
final SequenceBuilder sb = new SequenceBuilder();
final SequencePointable seq = (SequencePointable) SequencePointable.FACTORY.createPointable();
final VoidPointable p = (VoidPointable) VoidPointable.FACTORY.createPointable();
return new AbstractTaggedValueArgumentScalarEvaluator(args) {
@Override
protected void evaluate(TaggedValuePointable[] args, IPointable result)
throws SystemException {
try {
abvs.reset();
sb.reset(abvs);
for (int i = 0; i < args.length; ++i) {
TaggedValuePointable tvp = args[i];
if (tvp.getTag() == ValueTag.SEQUENCE_TAG) {
tvp.getValue(seq);
int seqLen = seq.getEntryCount();
for (int j = 0; j < seqLen; ++j) {
seq.getEntry(j, p);
sb.addItem(p);
}
} else {
sb.addItem(tvp);
}
}
sb.finish();
result.set(abvs);
} catch (IOException e) {
throw new SystemException(ErrorCode.SYSE0001);
}
}
};
}
@Override
protected IScalarEvaluator createEvaluator(IHyracksTaskContext ctx, IScalarEvaluator[] args)
throws AlgebricksException {
final UTF8StringPointable stringp1 =
(UTF8StringPointable) UTF8StringPointable.FACTORY.createPointable();
final UTF8StringPointable stringp2 =
(UTF8StringPointable) UTF8StringPointable.FACTORY.createPointable();
final UTF8StringPointable stringp3 =
(UTF8StringPointable) UTF8StringPointable.FACTORY.createPointable();
final ICharacterIterator charIterator1 = new UTF8StringCharacterIterator(stringp1);
final ICharacterIterator charIterator2 = new UTF8StringCharacterIterator(stringp2);
final SequencePointable seqp = (SequencePointable) SequencePointable.FACTORY.createPointable();
final TaggedValuePointable tvp =
(TaggedValuePointable) TaggedValuePointable.FACTORY.createPointable();
return new AbstractTaggedValueArgumentScalarEvaluator(args) {
@Override
protected void evaluate(TaggedValuePointable[] args, IPointable result)
throws SystemException {
// Default result is false.
byte[] booleanResult = new byte[2];
booleanResult[0] = ValueTag.XS_BOOLEAN_TAG;
booleanResult[1] = 0;
TaggedValuePointable tvp1 = args[0];
TaggedValuePointable tvp2 = args[1];
// Only accept strings as input.
if (tvp1.getTag() == ValueTag.SEQUENCE_TAG) {
tvp1.getValue(seqp);
if (seqp.getEntryCount() == 0) {
XDMConstants.setEmptyString(tvp);
tvp.getValue(stringp1);
} else {
throw new SystemException(ErrorCode.FORG0006);
}
} else {
if (!FunctionHelper.isDerivedFromString(tvp1.getTag())) {
throw new SystemException(ErrorCode.FORG0006);
}
tvp1.getValue(stringp1);
}
if (tvp2.getTag() == ValueTag.SEQUENCE_TAG) {
tvp2.getValue(seqp);
if (seqp.getEntryCount() == 0) {
XDMConstants.setEmptyString(tvp);
tvp.getValue(stringp2);
} else {
throw new SystemException(ErrorCode.FORG0006);
}
} else {
if (!FunctionHelper.isDerivedFromString(tvp2.getTag())) {
throw new SystemException(ErrorCode.FORG0006);
}
tvp2.getValue(stringp2);
}
int stringLength1 = stringp1.getStringLength();
int stringLength2 = stringp2.getStringLength();
charIterator1.reset();
charIterator2.reset();
// Third parameter is optional.
if (args.length > 2) {
TaggedValuePointable tvp3 = args[2];
if (!FunctionHelper.isDerivedFromString(tvp3.getTag())) {
throw new SystemException(ErrorCode.FORG0006);
}
tvp3.getValue(stringp3);
}
// TODO use the third value as collation
int stringCharOffset = stringLength1 - stringLength2;
// Only check if stringp2 can fit into stringp1.
if (stringCharOffset >= 0) {
// Only need to run comparisons if they both have a non empty string.
if (stringLength1 > 0 && stringLength2 > 0) {
// Move string one's cursor for comparison
for (; stringCharOffset > 0; --stringCharOffset) {
charIterator1.next();
}
int c1;
int c2;
while (true) {
c1 = charIterator1.next();
c2 = charIterator2.next();
if (c1 != c2) {
// Characters do not match
break;
}
if (c1 == ICharacterIterator.EOS_CHAR && c2 == ICharacterIterator.EOS_CHAR) {
// Checked the full length of search string.
booleanResult[1] = 1;
break;
}
}
} else if (stringLength2 == 0) {
booleanResult[1] = 1;
}
}
result.set(booleanResult, 0, 2);
}
};
}