/**
* (non-PHPdoc)
*
* @see library/POData/QueryProcessor/Expressions/Expressions.AbstractExpression::free()
*
* @return void
*/
public function free()
{
if (!is_null($this->parent)) {
$this->parent->free();
unset($this->parent);
}
if (!is_null($this->child)) {
$this->child->free();
unset($this->child);
}
}
/**
* Process an property access expression node for nullability
*
* @param PropertyAccessExpression $expression The property access
* expression node to process.
* @param AbstractExpression $parentExpression The parent expression of
* expression node to process.
* @param boolean $checkNullForMostChild Wheter to check null for
* most child node or not.
*
* @return LogicalExpression|RelationalExpression|null
*/
private function _processPropertyAccessNode(PropertyAccessExpression $expression, $parentExpression, $checkNullForMostChild)
{
$navigationsUsed = $expression->getNavigationPropertiesInThePath();
if (!empty($navigationsUsed)) {
$this->_navigationPropertiesUsedInTheExpression[] = $navigationsUsed;
}
$nullableExpTree = $expression->createNullableExpressionTree($checkNullForMostChild);
if ($parentExpression == null) {
return new LogicalExpression($nullableExpTree, $expression, ExpressionType::AND_LOGICAL);
}
return $nullableExpTree;
}