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+#ifndef _QTSELECTIONITERATOR_
+#define _QTSELECTIONITERATOR_
+
+#ifndef CPPSTDLIB
+#include <ospace/string.h> // STL<ToolKit>
+#else
+#include <string>
+#endif
+
+#include "qlparser/qtiterator.hh"
+#include "qlparser/qtoperation.hh"
+
+/*
+* This file is part of rasdaman community.
+*
+* Rasdaman community is free software: you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation, either version 3 of the License, or
+* (at your option) any later version.
+*
+* Rasdaman community is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with rasdaman community. If not, see <http://www.gnu.org/licenses/>.
+*
+* Copyright 2003, 2004, 2005, 2006, 2007, 2008, 2009 Peter Baumann /
+rasdaman GmbH.
+*
+* For more information please see <http://www.rasdaman.org>
+* or contact Peter Baumann via <baumann@rasdaman.com>.
+*/
+/*************************************************************
+ *
+ *
+ * COMMENTS:
+ *
+ ************************************************************/
+
+//@ManMemo: Module: {\bf qlparser}
+
+/*@Doc:
+
+An condition expression specified through a reference to
+an instance of the QtOperation sub-hierarchy, is evaluated for the actual input
+The boolean result determines if the tupel is passed to the output stream or not.
+So the method {\tt next()} reads tupels from its inputs until one can be
+passed to its caller. The class represents the WHERE condition in the query
+
+*/
+
+class QtSelectionIterator : public QtIterator
+{
+ public:
+ /// default constructor
+ QtSelectionIterator();
+
+ /// constructor getting a pointer to the parent
+ QtSelectionIterator( QtNode* node );
+
+ /// virtual destructor
+ virtual ~QtSelectionIterator();
+
+ /// return childs of the node
+ virtual QtNodeList* getChilds( QtChildType flag );
+
+ /// method for query rewrite
+ inline virtual void setInput( QtOperation* child, QtOperation* input);
+
+ /// optimizing load access
+// virtual void preOptimize();
+ /**
+ Trigger load optimization in the condition tree and pass the optimization step to
+ the input streams.
+ */
+
+ /// prints the tree
+ virtual void printTree( int tab, std::ostream& s = std::cout, QtChildType mode = QT_ALL_NODES );
+
+ /// prints the algebraic expression
+ virtual void printAlgebraicExpression( std::ostream& s = std::cout );
+
+ //@Man: Operations of the ONC protocol:
+ //@{
+ ///
+ QtDataList* next();
+ //@}
+
+ //@Man: Read/Write methods:
+ //@{
+ ///
+ //inline virtual void setParents();
+ ///
+ inline void setConditionTree( QtOperation* operation );
+ ///
+ inline QtOperation* getConditionTree();
+ //@}
+
+ /// method for identification of nodes
+ inline virtual const QtNodeType getNodeType() const;
+
+ /// type checking
+ virtual const QtTypeTuple& checkType();
+
+ private:
+ /// pointer to a tree representing the where part of the query
+ QtOperation* conditionTree;
+
+ /// attribute for identification of nodes
+ static const QtNodeType nodeType;
+};
+
+#include "qlparser/qtselectioniterator.icc"
+
+#endif
+
+