examples/org.eclipse.ocl.examples.interpreter/src/org/eclipse/ocl/examples/interpreter/console/ModelingLevel.java

/*******************************************************************************
 * Copyright (c) 2007, 2018 IBM Corporation and others.
 * All rights reserved.   This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v2.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v20.html
 *
 * Contributors:
 *   IBM - Initial API and implementation
 *******************************************************************************/

package org.eclipse.ocl.examples.interpreter.console;

import org.eclipse.emf.ecore.EObject;
import org.eclipse.ocl.ParserException;
import org.eclipse.ocl.examples.interpreter.internal.l10n.OCLInterpreterMessages;
import org.eclipse.ocl.helper.ConstraintKind;
import org.eclipse.ocl.helper.OCLHelper;
import org.eclipse.ocl.utilities.UMLReflection;


/**
 * Enumeration of modeling levels on which we can define OCL expressions, in
 * accordance with the OMG modeling stack.
 * 
 * @author Christian W. Damus (cdamus)
 */
public enum ModelingLevel {
    M2, M1;
    
    /**
     * Set the context of the specified OCL helper to the given element (in the
     * {@link #M1} case) or its metaclass ({@link #M2} case).
     * 
     * @param helper an OCL helper
     * @param factory a factory to help in obtaining a metaclass, where needed
     * @param element the selected context element
     * 
     * @return the kind of constraint to parse or to complete
     * 
     * @throws ParserException if the specified context is not valid for this
     *    modeling level
     */
    public <C, O, P> ConstraintKind setContext(OCLHelper<C, O, P, ?> helper, EObject element, IOCLFactory<C> factory)
    		throws ParserException {
        switch (this) {
            case M2:
            	C contextClassifier = factory.getContextClassifier(element);
            	if (contextClassifier == null) {
            		throw new ParserException(OCLInterpreterMessages.console_badContextForQuery);
            	}
                helper.setContext(contextClassifier);
                return ConstraintKind.INVARIANT;
            case M1:
                UMLReflection<?, C, O, P, ?, ?, ?, ?, ?, ?> uml =
                    helper.getOCL().getEnvironment().getUMLReflection();
                
                if (uml.isClassifier(element)) {
                    @SuppressWarnings("unchecked")
                    C classifier = (C) element;
                    helper.setContext(classifier);
                    return ConstraintKind.INVARIANT;
                } else if (uml.isOperation(element)) {
                    @SuppressWarnings("unchecked")
                    O operation = (O) element;
                    C classifier = uml.getOwningClassifier(operation);
                    helper.setOperationContext(classifier, operation);
                    return ConstraintKind.POSTCONDITION;
                } else if (uml.isProperty(element)) {
                    @SuppressWarnings("unchecked")
                    P property = (P) element;
                    C classifier = uml.getOwningClassifier(property);
                    helper.setAttributeContext(classifier, property);
                    return ConstraintKind.DERIVATION;
                } else {
                	throw new ParserException(OCLInterpreterMessages.console_badContextForConstraint);
                }
        }
        
        return null;
    }
}