examples/org.eclipse.ocl.examples.pivot/src/org/eclipse/ocl/examples/pivot/library/ConstrainedProperty.java

/**
 * <copyright>
 *
 * Copyright (c) 2011 E.D.Willink 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:
 *     E.D.Willink - initial API and implementation
 *
 * </copyright>
 *
 * $Id: ConstrainedProperty.java,v 1.1 2011/04/27 06:19:59 ewillink Exp $
 */
package org.eclipse.ocl.examples.pivot.library;

import org.eclipse.ocl.examples.domain.elements.DomainProperty;
import org.eclipse.ocl.examples.domain.elements.DomainType;
import org.eclipse.ocl.examples.domain.evaluation.DomainEvaluator;
import org.eclipse.ocl.examples.domain.evaluation.InvalidValueException;
import org.eclipse.ocl.examples.domain.library.AbstractProperty;
import org.eclipse.ocl.examples.domain.values.Value;
import org.eclipse.ocl.examples.pivot.ExpressionInOcl;
import org.eclipse.ocl.examples.pivot.evaluation.EvaluationEnvironment;
import org.eclipse.ocl.examples.pivot.evaluation.EvaluationVisitor;

/**
 * An instance of ConstrainedProperty supports evaluation of
 * a relationship defined by constraints.
 */
public class ConstrainedProperty extends AbstractProperty
{
	protected final ExpressionInOcl expressionInOcl;
	
	public ConstrainedProperty(ExpressionInOcl expressionInOcl) {
		this.expressionInOcl = expressionInOcl;
	}

	public Value evaluate(DomainEvaluator evaluator, DomainType returnType, Value sourceValue, DomainProperty property) throws InvalidValueException {
		EvaluationVisitor evaluationVisitor = (EvaluationVisitor)evaluator;
		EvaluationVisitor nestedVisitor = evaluationVisitor.createNestedEvaluator();
		EvaluationEnvironment nestedEvaluationEnvironment = nestedVisitor.getEvaluationEnvironment();
		nestedEvaluationEnvironment.add(expressionInOcl.getContextVariable(), sourceValue);
		return expressionInOcl.accept(nestedVisitor);
	}
}