OrCondExpression Class Reference

Represents XQuery disjunction or of two conditions. More...

#include <orcondexpression.h>

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List of all members.

Public Member Functions

 OrCondExpression (CondExpression *_left, CondExpression *_right)
 Constructor.
virtual ~OrCondExpression ()
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 ExpressionplaceSignOffs (vector< SignOffExpression * > &signoffs)
virtual void rewriteEmptyFuncts ()
virtual void rewriteVarstepCondExps ()
virtual void rewriteAggregateFuncts ()
virtual void print (OutputStream &dos) const
virtual void init (BufferNode *root)
virtual void eval (OutputStream &eos, Environment *env, unsigned modus)
virtual bool evalCond (OutputStream &eos, Environment *env, unsigned modus)

Private Attributes

CondExpressionleft
 The entered CondExpression on the left hand side of disjunction or.
CondExpressionright
 The entered CondExpression on the right hand side of disjunction or.


Detailed Description

Represents XQuery disjunction or of two conditions.

Represents XQuery disjunction or of two conditions, which takes therefore two CondExpression, e.g. fn:false() or fn:true() or $x/bib/book != /bib//book or fn:count($x) < 3, as arguments and returns the or disjunction of both conditions, i.e. returns true if at least one CondExpression is true, false otherwise.

Author:
Michael Schmidt

Gunnar Jehl

Version:
2.1
License:
Software License Agreement (BSD License)

Definition at line 52 of file orcondexpression.h.


Constructor & Destructor Documentation

OrCondExpression::OrCondExpression ( CondExpression _left,
CondExpression _right 
)

Constructor.

Constructor - creating object for two CondExpression.

Parameters:
[in] _left Pointer to a CondExpression object.
[in] _right Pointer to a CondExpression object.

Definition at line 37 of file orcondexpression.cpp.

OrCondExpression::~OrCondExpression (  )  [virtual]

Destructor.

Definition at line 41 of file orcondexpression.cpp.

References left, and right.


Member Function Documentation

void OrCondExpression::eval ( OutputStream eos,
Environment env,
unsigned  modus 
) [virtual]

Evaluates the expression in the given environment.

Evaluates the expression in the given environment. The evaluation takes place in the environment that is passed to this method. In addition, the parameter modus is one of the following: EVAL_QUERY, EVAL_QUERY_SILENT or EVAL_SIGNOFF (see also the corresponding defines for more information). This method implements the XQuery semantics for the standard expression types, but also the GCX specific extensions like signOff-statements.

Parameters:
[in] eos Pointer to a OutputStream object.
[in] env Pointer to an Environment object.
[in] modus The query evaluation mode.
Exceptions:
RuntimeException If illegal evaluation mode.

Reimplemented from Expression.

Definition at line 123 of file orcondexpression.cpp.

References Expression::eval(), EVAL_SIGNOFF, left, and right.

bool OrCondExpression::evalCond ( OutputStream eos,
Environment env,
unsigned  modus 
) [virtual]

Evaluates the corresponding CondExpression.

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 140 of file orcondexpression.cpp.

References EVAL_SIGNOFF, CondExpression::evalCond(), left, and right.

void OrCondExpression::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 68 of file orcondexpression.cpp.

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

void OrCondExpression::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 58 of file orcondexpression.cpp.

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

void OrCondExpression::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 63 of file orcondexpression.cpp.

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

void OrCondExpression::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 118 of file orcondexpression.cpp.

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

Expression * OrCondExpression::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 73 of file orcondexpression.cpp.

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

void OrCondExpression::print ( OutputStream dos  )  const [virtual]

Prints the expression.

Prints the expression.

Parameters:
[in] dos Pointer to a OutputStream object.
Return values:
void 

Implements Expression.

Definition at line 96 of file orcondexpression.cpp.

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

void OrCondExpression::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 53 of file orcondexpression.cpp.

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

void OrCondExpression::rewriteAggregateFuncts (  )  [virtual]

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

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

Return values:
void 

Reimplemented from Expression.

Definition at line 91 of file orcondexpression.cpp.

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

void OrCondExpression::rewriteEmptyFuncts (  )  [virtual]

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

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

Return values:
void 

Reimplemented from Expression.

Definition at line 81 of file orcondexpression.cpp.

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

void OrCondExpression::rewriteVarstepCondExps (  )  [virtual]

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

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 86 of file orcondexpression.cpp.

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

void OrCondExpression::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.

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 46 of file orcondexpression.cpp.

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


Member Data Documentation

The entered CondExpression on the left hand side of disjunction or.

The entered CondExpression on the left hand side of disjunction or, which is the first argument of the constructor.

Definition at line 141 of file orcondexpression.h.

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

The entered CondExpression on the right hand side of disjunction or.

The entered CondExpression on the right hand side of disjunction or, which is the second argument of the constructor.

Definition at line 148 of file orcondexpression.h.

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


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