XQuilla/include/xqilla/events/EventGenerator.hpp
2020-02-17 22:24:47 +01:00

68 lines
2.1 KiB
C++

/*
* Copyright (c) 2001, 2008,
* DecisionSoft Limited. All rights reserved.
* Copyright (c) 2004, 2018 Oracle and/or its affiliates. All rights reserved.
*
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _EVENTGENERATOR_HPP
#define _EVENTGENERATOR_HPP
#include <xqilla/framework/XQillaExport.hpp>
#include <xqilla/framework/ReferenceCounted.hpp>
#include <xqilla/runtime/ResultImpl.hpp>
class DynamicContext;
class EventHandler;
class ASTNode;
class QueryPathNode;
class XQILLA_API EventGenerator : public ReferenceCounted
{
public:
typedef RefCountPointer<EventGenerator> Ptr;
virtual ~EventGenerator() {}
/** Returns the result of this expression via the EventHandler provided.
An EventGenerator may be returned to be called as a tail call optimization */
virtual EventGenerator::Ptr generateEvents(EventHandler *events, DynamicContext *context) = 0;
static void generateAndTailCall(const EventGenerator::Ptr &generator, EventHandler *events,
DynamicContext *context)
{
EventGenerator::Ptr gen = generator;
while(gen.notNull()) {
gen = gen->generateEvents(events, context);
}
}
static Result createResult(const ASTNode *ast, const QueryPathNode *projection,
DynamicContext *context);
};
class XQILLA_API ASTNodeEventGenerator : public EventGenerator
{
public:
ASTNodeEventGenerator(const ASTNode *ast, bool preserveNS, bool preserveType);
virtual EventGenerator::Ptr generateEvents(EventHandler *events, DynamicContext *context);
protected:
const ASTNode *ast_;
bool preserveNS_, preserveType_;
};
#endif