Package com.togethersoft.openapi.sci.visitor

See
          Description

Class Diagram Summary
visitor

 

Interface Summary
SciElementVisitor	Visitor design pattern implementation for SciElements.
SciExpressionVisitor	Visitor design pattern implementation for SciExpressions.
SciFileVisitor
SciPackageVisitor
SciReferenceVisitor	Visitor design pattern implementation for SciReferences.
SciStatementVisitor	Visitor design pattern implementation for SciStatements.

 

Class Summary
SciElementVisitorAdapter	SciElementVisitorAdapter class extends SciElementVisitor functionality by providing an additional method visitElement.
SciExpressionVisitorAdapter	An empty implementation of SciExpressionVisitor interface.
SciStatementVisitorAdapter	An empty implementation of SciStatementVisitor interface.
SciVisitorUtil	This class contains a set of useful static methods for accepting a visitor by an enumeration of elements, expressions, statements or references.

 

Package com.togethersoft.openapi.sci.visitor Description

A set of classes and interfaces implementing Visitor pattern from GoF "Design Patterns" book.

"Visitors" are classes containing methods intended to perform certain actions upon different kinds of expressions (elements, statemets, references).

For example, a class implementing SciExpressionVisitor interface, defines methods for visiting different kinds of expressions: visitFunctionCallExpression, visitTypeCastExpression etc. When the accept method is invoked on an expression, then this method automatically determines a kind of this expression (FUNCTION_CALL, TYPE_CAST etc) and runs visitor's corresponding method to the kind of expression, passing expression as a parameter to that method.

This mechanism lets you define visitors perfoming similar actions for every kind of expressions (elements, statements, references) on their own manner - for example, a visitor printingExpressionVisitor can print expression's kind-specific commentary. These kind-specific actions have to be written in corresponding methods( visitFunctionCallExpression, visitTypeCastExpression etc). Now, when an expression invokes accept(printingExpressionVisitor) method, this visitor will print the comment corresponding to the kind of this expression.

"Adapter" classes (SciExpressionVisitorAdapter, SciElementVisitorAdapter etc) are simple implementations of corresponding "Visitor" interfaces.