CondOperandExpression Class Reference

Represents XQuery comparison of two operands with relational operators <, <=, >=, >, = or !=. More...

#include <condoperandexpression.h>

Inheritance diagram for CondOperandExpression:

Collaboration diagram for CondOperandExpression:

List of all members.

Public Member Functions

CondOperandExpression (OperandExpression *_left, COMP_TYPE _op, OperandExpression *_right)

Constructor.

virtual ~CondOperandExpression ()

virtual void scopeCheck (vector< unsigned > &def_vars, vector< unsigned > &introduced_vars, vector< unsigned > &violating_vars)

virtual void replaceVarId (unsigned old_id, unsigned new_id)

virtual void extractFSAMap (FSAMap *fsamap, unsigned parent_var)

virtual void extractParVarMap (ParVarMap *parvarmap)

virtual void extractDependencies (vector< DependencySet * > *depset)

virtual Expression * placeSignOffs (vector< SignOffExpression * > &signoffs)

virtual void rewriteEmptyFuncts ()

virtual void rewriteVarstepCondExps ()

virtual void rewriteAggregateFuncts ()

virtual void print (OutputStream &dos) const

virtual void init (BufferNode *root)

virtual bool evalCond (OutputStream &eos, Environment *env, unsigned modus)

Private Member Functions

bool evalRelOp (Value *left, COMP_TYPE op, Value *right)

Evaluates the two entered Value objects with respect to the entered COMP_TYPE.

COMP_TYPE invertOperator (COMP_TYPE ot)

Inverts the entered COMP_TYPE.

Private Attributes

OperandExpression * left

The entered OperandExpression on the left hand side of the entered COMP_TYPE.

COMP_TYPE op

The entered COMP_TYPE between the two entered OperandExpression.

OperandExpression * right

The entered OperandExpression on the right hand side of the entered COMP_TYPE.

Detailed Description

Represents XQuery comparison of two operands with relational operators <, <=, >=, >, = or !=.

Represents XQuery comparison of two operands with relational operators <, <=, >=, >, = or !=, which takes therefore two OperandExpression, e.g. $x/bib/book, "foo" or fn:count($x), and a COMP_TYPE, e.g. = or !=, as arguments and returns the evaluated value of the two OperandExpression with respect to COMP_TYPE, i.e. returns true if the two OperandExpression are in correct relationship to the COMP_TYPE, false otherwise.

Author:: Michael Schmidt
Gunnar Jehl

Version:: 2.1

License:: Software License Agreement (BSD License)

Definition at line 56 of file condoperandexpression.h.

Constructor & Destructor Documentation

CondOperandExpression::CondOperandExpression	(	OperandExpression *	_left,
		COMP_TYPE	_op,
		OperandExpression *	_right
	)

Constructor.

Constructor - creating object for a COMP_TYPE and two OperandExpression.

Parameters:

`[in]`	_left	Pointer to a OperandExpression object.
`[in]`	_op	COMP_TYPE.
`[in]`	_right	Pointer to a OperandExpression object.

Definition at line 38 of file condoperandexpression.cpp.

CondOperandExpression::~CondOperandExpression ( ) [virtual]

Destructor.

Definition at line 48 of file condoperandexpression.cpp.

References left, and right.

Member Function Documentation

bool CondOperandExpression::evalCond	(	OutputStream &	eos,
		Environment *	env,
		unsigned	modus
	)			`[virtual]`

Evaluates the corresponding CondExpression.

Parameters:

`[in]`	eos	Pointer to a OutputStream object.
`[in]`	env	Pointer to a Environment object.
`[in]`	modus	Evaluation modus.

Return values:

bool true if the corresponding CondExpression is true, false otherwise.

Exceptions:

RuntimeException

If illegal evaluation mode (argument: unsigned modus).

Implements CondExpression.

Definition at line 135 of file condoperandexpression.cpp.

References EVAL_QUERY, EVAL_SIGNOFF, evalRelOp(), OperandExpression::getNextValue(), invertOperator(), OperandExpression::isSingleValued(), left, op, OperandExpression::prepareOperand(), right, and OperandExpression::unprepareOperand().

bool CondOperandExpression::evalRelOp	(	Value *	left,
		COMP_TYPE	op,
		Value *	right
	)			`[private]`

Evaluates the two entered Value objects with respect to the entered COMP_TYPE.

Evaluates the two entered Value objects with respect to the entered COMP_TYPE to true or false.

Parameters:

`[in]`	left	Pointer to a Value object.
`[in]`	op	COMP_TYPE.
`[in]`	right	Pointer to a Value object.

Return values:

bool true if the two Value objects are in correct relationship with respect to the entered COMP_TYPE, false otherwise.

Definition at line 199 of file condoperandexpression.cpp.

References Value::getNumVal(), Value::getStrVal(), and Value::type.

Referenced by evalCond().

void CondOperandExpression::extractDependencies ( vector< DependencySet * > * depset ) [virtual]

Extracts the needed dependencies of a query.

Extracts the needed dependencies of a query, which are needed for constructing the ProjectionTree.

Parameters:

[in,out] depset Pointer to a vector containing Pointer to DependencySet objects.

Return values:

void

Reimplemented from Expression.

Definition at line 75 of file condoperandexpression.cpp.

References Expression::extractDependencies(), left, and right.

void CondOperandExpression::extractFSAMap	(	FSAMap *	fsamap,
		unsigned	parent_var
	)			`[virtual]`

Extracts the needed first straight ancestor (FSA) variables map.

Extracts the needed first straight ancestor (FSA) variables map, which is needed for correct insertion of SignOffExpression.

Parameters:

`[in,out]`	fsamap	Pointer to a FSAMap object.
`[in]`	parent_var	Parent variable.

Return values:

void

Reimplemented from Expression.

Definition at line 65 of file condoperandexpression.cpp.

References Expression::extractFSAMap(), left, and right.

void CondOperandExpression::extractParVarMap ( ParVarMap * parvarmap ) [virtual]

Extracts the needed parent variable (ParVar) map.

Extracts the needed parent variable (ParVar) map, which is needed for constructing the VariableTree.

Parameters:

[in,out] parvarmap Pointer to a ParVarMap object.

Return values:

void

Reimplemented from Expression.

Definition at line 70 of file condoperandexpression.cpp.

References Expression::extractParVarMap(), left, and right.

void CondOperandExpression::init ( BufferNode * root ) [virtual]

Initializes the query for evaluation.

Initializes the query for evaluation. Up to now only all required BufferIterator objects are created to speed up query evaluation.

Parameters:

[in] root Pointer to a BufferNode object.

Return values:

void

Reimplemented from Expression.

Definition at line 130 of file condoperandexpression.cpp.

References Expression::init(), left, and right.

COMP_TYPE CondOperandExpression::invertOperator ( COMP_TYPE ot ) [private]

Inverts the entered COMP_TYPE.

Inverts the entered COMP_TYPE, e.g. < results in >.

Parameters:

[in] ot COMP_TYPE.

Return values:

COMP_TYPE

The inverted COMP_TYPE of the original one.

Definition at line 239 of file condoperandexpression.cpp.

Referenced by evalCond().

Expression * CondOperandExpression::placeSignOffs ( vector< SignOffExpression * > & signoffs ) [virtual]

Places all signOff-statements in the corresponding query.

Places all signOff-statements in the corresponding query, which are needed for active garbage collection by removing Role from the BufferNode.

Parameters:

[in] signoffs Pointer to a vector containing Pointer to SignOffExpression objects.

Return values:

Expression*

Pointer to a Expression object (following expression in the corresponding query).

Reimplemented from Expression.

Definition at line 81 of file condoperandexpression.cpp.

References left, Expression::placeSignOffs(), and right.

void CondOperandExpression::print ( OutputStream & dos ) const [virtual]

Prints the expression.

Parameters:

[in] dos Pointer to a OutputStream object.

Return values:

void

Implements Expression.

Definition at line 105 of file condoperandexpression.cpp.

References op.

void CondOperandExpression::replaceVarId	(	unsigned	old_id,
		unsigned	new_id
	)			`[virtual]`

Replaces all matching variable IDs by a new one.

Replaces all matching variable IDs by a new one, which is needed in case of calling method rewriteVarsteps().

Parameters:

`[in]`	old_id	Old variable ID.
`[in]`	new_id	New variable ID, which should be introduced instead.

Return values:

void

Reimplemented from Expression.

Definition at line 60 of file condoperandexpression.cpp.

References left, Expression::replaceVarId(), and right.

void CondOperandExpression::rewriteAggregateFuncts ( ) [virtual]

Rewrites all arguments of all aggregate functions into an equivalent for-clause (with return-clause).

Return values:

void

Reimplemented from Expression.

Definition at line 100 of file condoperandexpression.cpp.

References left, Expression::rewriteAggregateFuncts(), and right.

void CondOperandExpression::rewriteEmptyFuncts ( ) [virtual]

Rewrites all fn:empty XQuery functions into equivalent fn:not(fn:exists) XQuery functions.

Return values:

void

Reimplemented from Expression.

Definition at line 90 of file condoperandexpression.cpp.

References left, Expression::rewriteEmptyFuncts(), and right.

void CondOperandExpression::rewriteVarstepCondExps ( ) [virtual]

Rewrites all if($x) if-conditions into equivalent if(fn:not(fn:empty($x))) XQuery expressions.

Return values:

void

Reimplemented from Expression.

Definition at line 95 of file condoperandexpression.cpp.

References left, Expression::rewriteVarstepCondExps(), and right.

void CondOperandExpression::scopeCheck	(	vector< unsigned > &	def_vars,
		vector< unsigned > &	introduced_vars,
		vector< unsigned > &	violating_vars
	)			`[virtual]`

Returns if all used variables were previously (through a for-clause) defined or if a variable leaves their defined scope.

Parameters:

`[in]`	def_vars	Vector containing all previously defined variables.
`[in]`	introduced_vars	Vector containing all up to this expression defined variables.
`[in]`	violating_vars	Vector containing all variables which violates the scope condition.

Return values:

void

Reimplemented from Expression.

Definition at line 53 of file condoperandexpression.cpp.

References left, right, and Expression::scopeCheck().

Member Data Documentation

OperandExpression * CondOperandExpression::left [private]

The entered OperandExpression on the left hand side of the entered COMP_TYPE.

The entered OperandExpression on the left hand side of the entered COMP_TYPE, which is the first argument of the constructor.

Definition at line 162 of file condoperandexpression.h.

Referenced by evalCond(), extractDependencies(), extractFSAMap(), extractParVarMap(), init(), placeSignOffs(), replaceVarId(), rewriteAggregateFuncts(), rewriteEmptyFuncts(), rewriteVarstepCondExps(), scopeCheck(), and ~CondOperandExpression().

COMP_TYPE CondOperandExpression::op [private]

The entered COMP_TYPE between the two entered OperandExpression.

The entered COMP_TYPE between the two entered OperandExpression, which is the second argument of the constructor.

Definition at line 169 of file condoperandexpression.h.

Referenced by evalCond(), and print().

OperandExpression * CondOperandExpression::right [private]

The entered OperandExpression on the right hand side of the entered COMP_TYPE.

The entered OperandExpression on the right hand side of the entered COMP_TYPE, which is the third argument of the constructor.

Definition at line 176 of file condoperandexpression.h.

Referenced by evalCond(), extractDependencies(), extractFSAMap(), extractParVarMap(), init(), placeSignOffs(), replaceVarId(), rewriteAggregateFuncts(), rewriteEmptyFuncts(), rewriteVarstepCondExps(), scopeCheck(), and ~CondOperandExpression().


Public Member Functions
	CondOperandExpression (OperandExpression _left, COMP_TYPE _op, OperandExpression _right)
	Constructor.
virtual	~CondOperandExpression ()
virtual void	scopeCheck (vector< unsigned > &def_vars, vector< unsigned > &introduced_vars, vector< unsigned > &violating_vars)
virtual void	replaceVarId (unsigned old_id, unsigned new_id)
virtual void	extractFSAMap (FSAMap *fsamap, unsigned parent_var)
virtual void	extractParVarMap (ParVarMap *parvarmap)
virtual void	extractDependencies (vector< DependencySet * > *depset)
virtual Expression *	placeSignOffs (vector< SignOffExpression * > &signoffs)
virtual void	rewriteEmptyFuncts ()
virtual void	rewriteVarstepCondExps ()
virtual void	rewriteAggregateFuncts ()
virtual void	print (OutputStream &dos) const
virtual void	init (BufferNode *root)
virtual bool	evalCond (OutputStream &eos, Environment *env, unsigned modus)
Private Member Functions
bool	evalRelOp (Value left, COMP_TYPE op, Value right)
	Evaluates the two entered Value objects with respect to the entered COMP_TYPE.
COMP_TYPE	invertOperator (COMP_TYPE ot)
	Inverts the entered COMP_TYPE.
Private Attributes
OperandExpression *	left
	The entered OperandExpression on the left hand side of the entered COMP_TYPE.
COMP_TYPE	op
	The entered COMP_TYPE between the two entered OperandExpression.
OperandExpression *	right
	The entered OperandExpression on the right hand side of the entered COMP_TYPE.