C++ item::Ptr类代码示例

Sequence FunctionLocalname::createSequence(DynamicContext* context, int flags) const
{
  XPath2MemoryManager* memMgr = context->getMemoryManager();

  Node::Ptr ctxNode;
  if(getNumArgs() == 1) {
    Sequence arg=getParamNumber(1,context)->toSequence(context);
    if(arg.isEmpty())
      return Sequence(context->getItemFactory()->createString(XERCES_CPP_NAMESPACE_QUALIFIER XMLUni::fgZeroLenString, context), memMgr);
    ctxNode=arg.first();
  }
  else {
    const Item::Ptr item = context->getContextItem();
    if(item==NULLRCP)
      XQThrow(FunctionException, X("FunctionLocalName::createSequence"),X("Undefined context item in fn:local-name [err:XPDY0002]"));
    if(!item->isNode())
      XQThrow(FunctionException, X("FunctionLocalName::createSequence"),X("The context item is not a node [err:XPTY0004]"));
    ctxNode=item;
	}

  ATQNameOrDerived::Ptr name = ctxNode->dmNodeName(context);
  if(name.notNull())
    return Sequence(context->getItemFactory()->createString(((const ATQNameOrDerived*)name.get())->getName(), context), memMgr);

  return Sequence(context->getItemFactory()->createString(XERCES_CPP_NAMESPACE_QUALIFIER XMLUni::fgZeroLenString, context), memMgr);
}

Item::Ptr UTransform::TransformResult::next(DynamicContext *context)
{
    context->testInterrupt();

    AutoVariableStoreReset reset(context, &scope_);

    if(toDo_) {
        toDo_ = false;

        NodeSet copiedNodes = NodeSet(nodecompare(context));

        VectorOfCopyBinding::const_iterator end = transform_->getBindings()->end();
        for(VectorOfCopyBinding::const_iterator it = transform_->getBindings()->begin();
                it != end; ++it) {
            if((*it)->qname_ == 0) continue;

            Sequence values = (*it)->expr_->createResult(context)->toSequence(context);

            // Keep a record of the nodes that have been copied
            Result valIt = values;
            Item::Ptr val;
            while((val = valIt->next(context)).notNull()) {
                copiedNodes.insert((Node*)val.get());
            }

            scope_.setVar((*it)->uri_, (*it)->name_, values);
        }

        // Get the pending update list
        PendingUpdateList pul = transform_->getModifyExpr()->createUpdateList(context);

        // Check that the targets of the pending updates are copied nodes
        for(PendingUpdateList::const_iterator i = pul.begin(); i != pul.end(); ++i) {
            Node::Ptr target = i->getTarget();
            while(copiedNodes.find(target) == copiedNodes.end()) {
                target = target->dmParent(context);
                if(target.isNull()) {
                    XQThrow3(StaticErrorException,X("UTransform::staticTyping"),
                             X("The target node of an update expression in the transform expression is not a node from the copy clauses [err:XUDY0014]"), &(*i));
                }
            }
        }

        // Apply the updates
        AutoDelete<UpdateFactory> ufactory(context->createUpdateFactory());
        ufactory->applyUpdates(pul, context, transform_->getRevalidationMode());

        // Execute the return expression
        result_ = transform_->getReturnExpr()->createResult(context);
    }

    Item::Ptr result = result_->next(context);

    if(result.isNull()) {
        result_ = 0;
        return 0;
    }

    return result;
}

Item::Ptr PromoteNumericResult::next(DynamicContext *context)
{
  Item::Ptr item = parent_->next(context);
  if(item.notNull()) {
    assert(item->isAtomicValue());
    const AnyAtomicType *atomic = (const AnyAtomicType *)item.get();

    // 3. For each numeric item in the atomic sequence that can be promoted to the expected atomic type using
    //    the promotion rules in B.1 Type Promotion, the promotion is done.
    if(atomic->isNumericValue()) {
      try {
        const Numeric::Ptr promotedType = ((const Numeric*)atomic)->
          promoteTypeIfApplicable(typeIndex_, context);
        if(promotedType.notNull()) {
          item = promotedType;
        }
      } catch (XPath2TypeCastException &e) {
        XQThrow(XPath2ErrorException, X("SequenceType::AtomicTypeConvertFunctionArgResult::next"),
                 X("Numeric type promotion failed (for promotable type)"));
      } catch (const XMLException& e) {
        XQThrow(XPath2ErrorException, X("SequenceType::AtomicTypeConvertFunctionArgResult::next"),
                 X("Numeric type promotion failed (for promotable type)"));
      }
    }
  }
  else {
    parent_ = 0;
  }

  return item;
}

int main(int argc, char *argv[]) {
  // Initialise Xerces-C and XQilla by creating the factory object
  XQilla xqilla;

  // Parse an XQuery expression
  // (AutoDelete deletes the object at the end of the scope)
  AutoDelete<XQQuery> query(xqilla.parse(X("foo/bar/@baz")));

  // Create a context object
  AutoDelete<DynamicContext> context(query->createDynamicContext());

  // Parse a document, and set it as the context item
  Sequence seq = context->resolveDocument(X("foo.xml"));
  if(!seq.isEmpty() && seq.first()->isNode()) {
    context->setContextItem(seq.first());
    context->setContextPosition(1);
    context->setContextSize(1);
  }

  // Execute the query, using the context
  Result result = query->execute(context);

  // Iterate over the results, printing them
  Item::Ptr item;
  while(item = result->next(context)) {
    std::cout << UTF8(item->asString(context)) << std::endl;
  }

  return 0;
}

ContainerBase *LookupIndexFunction::getContainerArg(DynamicContext *context, bool lookup) const
{
	if(container_ != 0) return container_;

	if(!_args[0]->isConstant() && !lookup) return 0;

	DbXmlConfiguration *conf = GET_CONFIGURATION(context);

	Item::Ptr containerName = getParamNumber(1, context)->next(context);

	try {
		XmlContainer container = DbXmlUri::openContainer(XMLChToUTF8(containerName->asString(context)).str(),
			conf->getManager(), conf->getTransaction());

		Container *tcont = (Container*)container;
		conf->getMinder()->addContainer(tcont);
		return tcont;
	}
	catch(XmlException &e) {
		e.setLocationInfo(this);
		throw;
	}

	// Never reached
	return 0;
}

Sequence FunctionSentences::createSequence(DynamicContext* context, int flags) const
{
  XPath2MemoryManager* memMgr = context->getMemoryManager();

  // If the value of $operand1 is the empty sequence, the empty sequence is returned.
  Item::Ptr inputString = getParamNumber(1,context)->next(context);
  if(inputString.isNull())
    return Sequence(memMgr);

  const XMLCh *input=inputString->asString(context);
  AutoDeallocate<XMLCh> buf(UnicodeTransformer::sentences(input, memMgr), memMgr);

  XMLCh* rb = buf.get();
  XMLCh* start = NULL;
  Sequence resultSeq(0, memMgr);

  // Build sequence
  for (int i = 0; rb[i]; i++) {
    if (rb[i] != UTF8PROC_SB_MARK)
      continue;

    rb[i] = 0;
    if (rb[i+1] == 0 || rb[i+1] != UTF8PROC_SB_MARK) {
      if (start != NULL)
        resultSeq.addItem(context->getItemFactory()->createString(start, context));
      start = rb + (i+1);
    }
  }

  return resultSeq;
}

Sequence FunctionDocument::createSequence(DynamicContext* context, int flags) const
{
  const XMLCh *baseURI;
  if(getNumArgs() == 2) {
    baseURI = ((Node*)getParamNumber(2, context)->next(context).get())->dmBaseURI(context).first()->asString(context);
  }
  else {
    baseURI = context->getBaseURI();
  }

  Sequence result(context->getMemoryManager());
  Result args = getParamNumber(1, context);
  Item::Ptr uriArg;
  while((uriArg = args->next(context)).notNull()) {
    const XMLCh *uri = uriArg->asString(context);
    if(!XPath2Utils::isValidURI(uri, context->getMemoryManager()))
      XQThrow(FunctionException, X("FunctionDocument::createSequence"), X("Invalid argument to fn:document function [err:FODC0005]"));

    try {
      XMLUri base(baseURI);
      XMLUri full(&base, uri);
      uri = context->getMemoryManager()->getPooledString(full.getUriText());
    }
    catch(MalformedURLException &e){
      XQThrow(FunctionException, X("FunctionDocument::createSequence"), X("Invalid argument to resolve-uri [err:FORG0002]"));
    }

    result.joinSequence(context->resolveDocument(uri, this, context->getProjection() ? queryPathTree_ : 0));
  }

  return result;
}

Item::Ptr MetaDataFunction::MetaDataResult::getSingleResult(DynamicContext *context) const
{
	// Get the node argument
	Item::Ptr node = 0;
	if(func_->getNumArgs() == 1) {
		// node argument is the context item
		node = context->getContextItem();
		if(node == NULLRCP || !node->isNode()) {
			XQThrow(FunctionException,X("MetaDataFunction::MetaDataResult::getSingleResult"),
				 X("The context item is not a node in function dbxml:metadata [err:FODC0001]"));
		}
	} else {
		// node argument is given
		node = func_->getParamNumber(2, context)->next(context);
	}

	// Resolve the string argument as a QName
	const XMLCh *uri, *name;
	func_->getQNameArg(1, uri, name, context);

	// Lookup the metadata
	const DbXmlNodeImpl *nodeImpl = (const DbXmlNodeImpl*)node->getInterface(DbXmlNodeImpl::gDbXml);
	DBXML_ASSERT(nodeImpl != 0);

	return nodeImpl->getMetaData(uri, name, context);
}

Sequence FunctionDoc::createSequence(DynamicContext* context, int flags) const
{
  Item::Ptr uriArg = getParamNumber(1,context)->next(context);
  
  if(uriArg.isNull()) {
    return Sequence(context->getMemoryManager());
  }
  
  const XMLCh *uri = uriArg->asString(context);

  // on Windows, we can have URIs using \ instead of /; let's normalize them
  if(uri != 0) {
    unsigned int len = XPath2Utils::uintStrlen(uri);
    AutoDeleteArray<XMLCh> newURI(new XMLCh[len + 1]);

    const XMLCh *src = uri;
    XMLCh *dst = newURI;
    while(*src != 0) {
      if(*src == '\\') *dst = '/';
      else *dst = *src;

      ++src; ++dst;
    }
    *dst = 0;

    uri = context->getMemoryManager()->getPooledString(newURI);
  }

  if(!XPath2Utils::isValidURI(uri, context->getMemoryManager()))
    XQThrow(FunctionException, X("FunctionDoc::createSequence"), X("Invalid argument to fn:doc function [err:FODC0005]"));

  return context->resolveDocument(uri, this, context->getProjection() ? queryPathTree_ : 0);
}

Item::Ptr XQCastAs::CastAsResult::getSingleResult(DynamicContext *context) const
{
  // The semantics of the cast expression are as follows:
  //    1. Atomization is performed on the input expression.
  Result toBeCasted(_di->getExpression()->createResult(context));

  const Item::Ptr first = toBeCasted->next(context);

  if(first == NULLRCP) {
    //    3. If the result of atomization is an empty sequence:
    //       1. If ? is specified after the target type, the result of the cast expression is an empty sequence.
    //       2. If ? is not specified after the target type, a type error is raised [err:XPTY0004].
    if(_di->getSequenceType()->getOccurrenceIndicator() == SequenceType::EXACTLY_ONE) {
      XQThrow(TypeErrorException,X("XQCastAs::CastAsResult::getSingleResult"),
              X("The input to a non-optional cast as expression is an empty sequence [err:XPTY0004]"));
    }
    else {
      return 0;
    }
  }

  const Item::Ptr second = toBeCasted->next(context);

  //    2. If the result of atomization is a sequence of more than one atomic value, a type error is raised.[err:XPTY0004]
  if(second != NULLRCP) {
    XQThrow(TypeErrorException,X("XQCastAs::CastAsResult::getSingleResult"),
            X("The input to a cast as expression is more than one atomic value [err:XPTY0004]"));
  }

  //    4. If the result of atomization is a single atomic value, the result of the cast expression depends on the input type and the target type.
  //       The normative definition of these rules is given in [XQuery 1.0 and XPath 2.0 Functions and Operators].
  return _di->cast((const AnyAtomicType*)first.get(), context);
}

PendingUpdateList UInsertAsLast::createUpdateList(DynamicContext *context) const
{
  Node::Ptr node = (Node*)target_->createResult(context)->next(context).get();

  if(node->dmNodeKind() != Node::element_string &&
     node->dmNodeKind() != Node::document_string)
    XQThrow(XPath2TypeMatchException,X("UInsertAsLast::createUpdateList"),
            X("It is a type error for the target expression of an insert as last expression not to be a single element "
              "or document [err:XUTY0005]"));

  Sequence alist(context->getMemoryManager());
  Sequence clist(context->getMemoryManager());

  Result value = source_->createResult(context);
  Item::Ptr item;
  while((item = value->next(context)).notNull()) {
    if(((Node*)item.get())->dmNodeKind() == Node::attribute_string) {
      if(!clist.isEmpty())
        XQThrow(ASTException,X("UInsertAsLast::createUpdateList"),
                X("Attribute nodes must occur before other nodes in the source expression for an insert as last expression [err:XUTY0004]"));

      //    b. No attribute node in $alist may have a QName whose implied namespace binding conflicts with a namespace
      //       binding in the "namespaces" property of $target [err:XUDY0023].  
      ATQNameOrDerived::Ptr qname = ((Node*)item.get())->dmNodeName(context);
      if(qname->getURI() != 0 && *(qname->getURI()) != 0) {
        ATAnyURIOrDerived::Ptr uri = FunctionNamespaceURIForPrefix::uriForPrefix(qname->getPrefix(), node, context, this);
        if(uri.notNull() && !XPath2Utils::equals(uri->asString(context), qname->getURI())) {
          XMLBuffer buf;
          buf.append(X("Implied namespace binding for the insert as last expression (\""));
          buf.append(qname->getPrefix());
          buf.append(X("\" -> \""));
          buf.append(qname->getURI());
          buf.append(X("\") conflicts with those already existing on the parent element of the target attribute [err:XUDY0023]"));
          XQThrow3(DynamicErrorException, X("UInsertInto::createUpdateList"), buf.getRawBuffer(), this);
        }
      }

      alist.addItem(item);
    }
    else
      clist.addItem(item);
  }

  PendingUpdateList result;

  if(!alist.isEmpty()) {
    // 3. If $alist is not empty and into is specified, the following checks are performed:
    //    a. $target must be an element node [err:XUTY0022].
    if(node->dmNodeKind() == Node::document_string)
      XQThrow(XPath2TypeMatchException,X("UInsertInto::createUpdateList"),
              X("It is a type error if an insert expression specifies the insertion of an attribute node into a document node [err:XUTY0022]"));
    result.addUpdate(PendingUpdate(PendingUpdate::INSERT_ATTRIBUTES, node, alist, this));
  }
  if(!clist.isEmpty()) {
    result.addUpdate(PendingUpdate(PendingUpdate::INSERT_INTO_AS_LAST, node, clist, this));
  }

  return result;
}

EventGenerator::Ptr XQCopy::generateEventsImpl(const Item::Ptr &toBeCopied, EventHandler *events, DynamicContext *context,
                                               bool preserveNS, bool preserveType) const
{
  if(!toBeCopied->isNode()) {
    toBeCopied->generateEvents(events, context, preserveNS, preserveType);
    return 0;
  }

  Node *node = (Node*)toBeCopied.get();

  if(node->dmNodeKind() == Node::element_string) {
    NoInheritFilter niFilter(events, context->getMemoryManager());
    if(!inheritNamespaces_) events = &niFilter;

    AnyAtomicType::Ptr itemName = node->dmNodeName(context);
    const ATQNameOrDerived *pQName = (const ATQNameOrDerived*)itemName.get();
    const XMLCh *prefix = emptyToNull(pQName->getPrefix());
    const XMLCh *uri = emptyToNull(pQName->getURI());
    const XMLCh *localname = pQName->getName();

    events->startElementEvent(prefix, uri, localname);

    ElemConstructFilter elemFilter(events, this, context->getMemoryManager());

    if(copyNamespaces_) {
      Result nsnodes = node->dmNamespaceNodes(context, this);
      Item::Ptr ns;
      while((ns = nsnodes->next(context)).notNull()) {
        ns->generateEvents(&elemFilter, context, preserveNS, preserveType);
      }
    }

    for(VectorOfASTNodes::const_iterator itCont = children_.begin(); itCont != children_.end (); ++itCont) {
      (*itCont)->generateAndTailCall(&elemFilter, context, preserveNS, preserveType);
    }

    // TBD validation and type - jpcs
    const XMLCh *typeURI = SchemaSymbols::fgURI_SCHEMAFORSCHEMA;
    const XMLCh *typeName = DocumentCache::g_szUntyped;

    events->endElementEvent(prefix, uri, localname, typeURI, typeName);
  }
  else if(node->dmNodeKind() == Node::document_string) {
    events->startDocumentEvent(0, 0);

    DocConstructFilter filter(events, this);

    for(VectorOfASTNodes::const_iterator itCont = children_.begin(); itCont != children_.end (); ++itCont) {
      (*itCont)->generateAndTailCall(&filter, context, preserveNS, preserveType);
    }

    events->endDocumentEvent();
  }
  else {
    node->generateEvents(events, context, preserveNS, preserveType);
  }

  return 0;
}

Result XQContextItem::result(DynamicContext *context, const LocationInfo *info)
{
  const Item::Ptr item = context->getContextItem();
  if(item.isNull()) {
    XQThrow3(DynamicErrorException,X("XQContextItem::result"),
             X("It is an error for the context item to be undefined when using it [err:XPDY0002]"), info);
  }
  return item;
}

Result XQContextItem::createResult(DynamicContext* context, int flags) const
{
  const Item::Ptr item = context->getContextItem();
  if(item.isNull()) {
    XQThrow(DynamicErrorException,X("XQContextItem::ContextItemResult::createResult"),
             X("It is an error for the context item to be undefined when using it [err:XPDY0002]"));
  }
  return item;
}

Sequence FunctionMinutesFromDateTime::createSequence(DynamicContext* context, int flags) const
{
  XPath2MemoryManager* memMgr = context->getMemoryManager();

  Item::Ptr arg = getParamNumber(1, context)->next(context);
  if(arg.isNull()) return Sequence(memMgr);

  return Sequence(((const ATDateTimeOrDerived*)arg.get())->getMinutes(context), memMgr);
}