org.eclipse.ocl.EvaluationVisitor Maven / Gradle / Ivy
/**
*
*
* Copyright (c) 2007 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM - Initial API and implementation
*
*
*
* $Id: EvaluationVisitor.java,v 1.1 2007/01/25 18:24:37 cdamus Exp $
*/
package org.eclipse.ocl;
import java.util.Map;
import java.util.Set;
import org.eclipse.ocl.expressions.OCLExpression;
import org.eclipse.ocl.utilities.Visitable;
import org.eclipse.ocl.utilities.Visitor;
/**
* A specialized visitor that is used for evaluation an
* {@linkplain OCLExpression OCL expression} by walking its AST.
*
* See the {@link Environment} class for a description of the
* generic type parameters of this class.
*
*
* @author Tim Klinger (tklinger)
* @author Christian W. Damus (cdamus)
*/
public interface EvaluationVisitor
extends Visitor {
/**
* Obtains the environment that provides the metamodel semantics for the
* expression to be evaluated.
*
* @return the environment
*/
public Environment getEnvironment();
/**
* Obtains the evaluation environment that keeps track of variable values
* and knows how to call operations, navigate properties, etc.
*
* @return the evaluation environment
*/
public EvaluationEnvironment getEvaluationEnvironment();
/**
* Obtains the mapping of model classes to their extends.
*
* @return the extent map
*/
public Map> getExtentMap();
/**
* Evaluates the specified expression on the current "self" context
* object. This result type of this expression may be any type. An
* implementation will typically just call {@link Visitable#accept(Visitor)}
* on the expression, but is free to elaborate on that. Thus,
* clients should not simply ask the expression to accept this
* visitor.
*
* @param expression the expression to evaluate
*
* @return the value of the expression
*/
public Object visitExpression(OCLExpression expression);
/**
* Checks that the specified constraint is satisfied by the
* current "self" context object or, in the case of an operation body
* condition, evaluates the body expression.
*
* @return for boolean-valued constraints (invariant, precondition, postcondition)
* Boolean.TRUE if the constraint holds and Boolean.FALSE
* if it is violated (including evaluations that result in OclInvalid).
* For operation body conditions, the value of the operation result
*
* @throws IllegalArgumentException if the constraint is one that must
* be boolean-valued but the computed result is not of boolean type
* (or OclInvalid)
*/
public Object visitConstraint(CT constraint);
}