plugins/org.eclipse.gmf.codegen/templates/xpt/expressions/OCLExpressionFactory.xpt

/*
 * Copyright (c) 2007, 2010 Borland Software 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:
 *    Dmitry Stadnik (Borland) - initial API and implementation
 */

«IMPORT 'http://www.eclipse.org/gmf/2009/GenModel'»

«DEFINE OCLExpressionFactory FOR gmfgen::GenExpressionInterpreter-»
«EXPAND xpt::Common::copyright FOR container.editorGen-»
package «container.expressionsPackageName»;

«EXPAND xpt::Common::generatedClassComment»
public class «className» {

	«EXPAND _initInterpreterFactory»

	«EXPAND xpt::Common::generatedMemberComment»
	public static «container.getAbstractExpressionQualifiedClassName()» getExpression(String body, org.eclipse.emf.ecore.EClassifier context, java.util.Map«EXPAND CodeStyle::G2('String', 'org.eclipse.emf.ecore.EClassifier') FOR container.editorGen.diagram» environment) {
		return new Expression(body, context, environment);
	}

	«EXPAND xpt::Common::generatedMemberComment('This method will become private in the next release')»«REM»FIXME private or completely remove in the next release «ENDREM»
	public static «container.getAbstractExpressionQualifiedClassName()» getExpression(String body, org.eclipse.emf.ecore.EClassifier context) {
		return getExpression(body, context, «EXPAND CodeStyle::emptyMap('String, org.eclipse.emf.ecore.EClassifier') FOR container.editorGen.diagram»);
	}

	«EXPAND xpt::Common::generatedMemberComment»
	private static class Expression extends «container.getAbstractExpressionQualifiedClassName()» {

		«EXPAND xpt::Common::generatedMemberComment»
		private final org.eclipse.ocl.ecore.OCL oclInstance;

		«EXPAND xpt::Common::generatedMemberComment»
		private org.eclipse.ocl.ecore.OCLExpression oclExpression;

		«EXPAND xpt::Common::generatedMemberComment»
		public Expression(String body, org.eclipse.emf.ecore.EClassifier context, java.util.Map«EXPAND CodeStyle::G2('String', 'org.eclipse.emf.ecore.EClassifier') FOR container.editorGen.diagram» environment) {
			super(body, context);
			oclInstance = org.eclipse.ocl.ecore.OCL.newInstance();
			initCustomEnv(oclInstance.getEnvironment(), environment);
			«REM»
			   I've moved expression initialization right into constructor because:
			   - Caching and weak references done at the caller are more effective for this usecase (we have an instance/static field to reference this Expression anyway)
			   - Expression's status is known right away, not only after protected getQuery get invoked 
			«ENDREM»«-»
			org.eclipse.ocl.ecore.OCL.Helper oclHelper = oclInstance.createOCLHelper();
			oclHelper.setContext(context());
			try {
				oclExpression = oclHelper.createQuery(body());
				setStatus(org.eclipse.core.runtime.IStatus.OK, null, null);
			} catch (org.eclipse.ocl.ParserException e) {
				setStatus(org.eclipse.core.runtime.IStatus.ERROR, e.getMessage(), e);
			}
		}

		«EXPAND xpt::Common::generatedMemberComment»
		«EXPAND CodeStyle::SuppressWarnings('"rawtypes"') FOR container.editorGen.diagram-»
		protected Object doEvaluate(Object context, java.util.Map env) {
			if (oclExpression == null) {
				return null;
			}
			// on the first call, both evalEnvironment and extentMap are clear, for later we have finally, below.
			org.eclipse.ocl.EvaluationEnvironment«EXPAND CodeStyle::G('?,?,?,?,?') FOR container.editorGen.diagram»  evalEnv = oclInstance.getEvaluationEnvironment();
			// initialize environment«REM»Using Object below because Map env comes as raw type, and Object(unlike String) works fine for both Iterator<Type> = iterable.iterator() and for (Type a : iterable) code styles «ENDREM»
			«EXPAND CodeStyle::iterate('nextKey', 'Object', 'env.keySet()') FOR container.editorGen.diagram-»
				evalEnv.replace((String) nextKey, env.get(nextKey));
			}
			try {
				Object result = oclInstance.evaluate(context, oclExpression);
				return oclInstance.isInvalid(result) ? null : result;
			} finally {
				evalEnv.clear();
				oclInstance.setExtentMap(null); // clear allInstances cache, and get the oclInstance ready for the next call
			}
		}

		«EXPAND xpt::Common::generatedMemberComment»
		private static void initCustomEnv(org.eclipse.ocl.Environment«EXPAND CodeStyle::G('?,org.eclipse.emf.ecore.EClassifier,?,?,?,org.eclipse.emf.ecore.EParameter,?,?,?,?,?,?') FOR container.editorGen.diagram» ecoreEnv, java.util.Map«EXPAND CodeStyle::G2('String', 'org.eclipse.emf.ecore.EClassifier') FOR container.editorGen.diagram» environment) {
			«EXPAND initializeEnvironment('ecoreEnv')-»
			«EXPAND CodeStyle::iterate('varName', 'String', 'environment.keySet()') FOR container.editorGen.diagram-»
				org.eclipse.emf.ecore.EClassifier varType = «EXPAND CodeStyle::castTyped('org.eclipse.emf.ecore.EClassifier') FOR container.editorGen.diagram»environment.get(varName);
				ecoreEnv.addElement(varName, createVar(ecoreEnv, varName, varType), false);
			}
		}

		«EXPAND xpt::Common::generatedMemberComment»
		private static org.eclipse.ocl.ecore.Variable createVar(org.eclipse.ocl.Environment«EXPAND CodeStyle::G('?,org.eclipse.emf.ecore.EClassifier,?,?,?,?,?,?,?,?,?,?') FOR container.editorGen.diagram» ecoreEnv, String name, org.eclipse.emf.ecore.EClassifier type) {
			org.eclipse.ocl.ecore.Variable var = org.eclipse.ocl.ecore.EcoreFactory.eINSTANCE.createVariable();
			var.setName(name);
			var.setType(«EXPAND CodeStyle::castTyped('org.eclipse.emf.ecore.EClassifier') FOR container.editorGen.diagram»ecoreEnv.getUMLReflection().getOCLType(type));
			return var;
		}
	}
	«EXPAND additions-»
}
«ENDDEFINE»

«REM»
  Clients may override if they don't need
«ENDREM»
«DEFINE initializeEnvironment(String environmentVar) FOR gmfgen::GenExpressionInterpreter-»
// Use EObject as implicit root class for any object, to allow eContainer() and other EObject operations from OCL expressions
org.eclipse.ocl.options.ParsingOptions.setOption(«environmentVar», org.eclipse.ocl.options.ParsingOptions.implicitRootClass(«environmentVar»), org.eclipse.emf.ecore.EcorePackage.eINSTANCE.getEObject());
«ENDDEFINE»

«DEFINE additions FOR gmfgen::GenExpressionInterpreter»«ENDDEFINE»

// just to avoid identical piece of template in the RegexpExpressionFactory
«DEFINE _initInterpreterFactory FOR gmfgen::GenExpressionInterpreter-»
	«EXPAND xpt::Common::generatedMemberComment»
	private final «container.getAbstractExpressionQualifiedClassName()»[] expressions; 

	«EXPAND xpt::Common::generatedMemberComment»
	protected «className»() {
		this.expressions = new «container.getAbstractExpressionQualifiedClassName()»[«expressions->size()»];
	}
	
	«EXPAND xpt::Common::generatedMemberComment»
	public static «container.getAbstractExpressionQualifiedClassName()» getExpression(int index, org.eclipse.emf.ecore.EClassifier context) {
		«className» cached = «EXPAND plugin::Activator::instanceAccess FOR container.editorGen».get«className»();
		if (cached == null) {
			«EXPAND plugin::Activator::instanceAccess FOR container.editorGen».set«className»(cached = new «className»());
		}
		if (index < 0 || index >= cached.expressions.length) {
			throw new IllegalArgumentException();
		}
		if (cached.expressions[index] == null) {
			final String[] exprBodies = new String[] {
				«FOREACH expressions.getBodyString() AS b»«b», «EXPAND xpt::Common::nonNLS»
				«ENDFOREACH-»
			};
			cached.expressions[index] = getExpression(exprBodies[index], context);
		}
		return cached.expressions[index];
	}
«ENDDEFINE»