1 files changed, 143 insertions, 0 deletions
diff --git a/plugins/toolsmiths/validation/org.eclipse.papyrus.toolsmiths.validation.properties/src/org/eclipse/papyrus/toolsmiths/validation/properties/internal/trace/ComposedSourceTraceHelper.java b/plugins/toolsmiths/validation/org.eclipse.papyrus.toolsmiths.validation.properties/src/org/eclipse/papyrus/toolsmiths/validation/properties/internal/trace/ComposedSourceTraceHelper.java
new file mode 100644
index 00000000000..ea497b61ef9
--- /dev/null
+++ b/plugins/toolsmiths/validation/org.eclipse.papyrus.toolsmiths.validation.properties/src/org/eclipse/papyrus/toolsmiths/validation/properties/internal/trace/ComposedSourceTraceHelper.java
@@ -0,0 +1,143 @@
+/*****************************************************************************
+ * Copyright (c) 2021 Christian W. Damus, CEA LIST, and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *   Christian W. Damus - Initial API and implementation
+ *
+ *****************************************************************************/
+
+package org.eclipse.papyrus.toolsmiths.validation.properties.internal.trace;
+
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+import java.util.function.BiFunction;
+
+import org.eclipse.emf.ecore.EObject;
+import org.eclipse.papyrus.customization.properties.generation.generators.IGenerator;
+import org.eclipse.papyrus.infra.constraints.ConstraintDescriptor;
+import org.eclipse.papyrus.infra.constraints.ValueProperty;
+import org.eclipse.papyrus.infra.properties.contexts.DataContextElement;
+import org.eclipse.papyrus.infra.properties.contexts.Section;
+import org.eclipse.papyrus.infra.properties.contexts.View;
+
+/**
+ * A source trace helper that is composed of other helpers to which it delegates
+ * in turn until it gets a result.
+ */
+public class ComposedSourceTraceHelper implements SourceTraceHelper {
+
+	private final List<SourceTraceHelper> delegates;
+
+	public ComposedSourceTraceHelper() {
+		super();
+
+		delegates = List.of(new ExplicitSourceTraceHelper(),
+				new ImplicitUMLSourceTraceHelper(),
+				new ImplicitEcoreSourceTraceHelper());
+	}
+
+	@Override
+	public EObject getSourceElement(EObject propertiesElement) {
+		return iterate(propertiesElement, null, SourceTraceHelper::getSourceElement);
+	}
+
+	@Override
+	public List<? extends EObject> getNestedPackages(EObject sourcePackage) {
+		return iterate(sourcePackage, List.of(), SourceTraceHelper::getNestedPackages);
+	}
+
+	@Override
+	public List<? extends EObject> getClasses(EObject sourcePackage) {
+		return iterate(sourcePackage, List.of(), SourceTraceHelper::getClasses);
+	}
+
+	@Override
+	public List<? extends EObject> getProperties(EObject sourceClass) {
+		return iterate(sourceClass, List.of(), SourceTraceHelper::getProperties);
+	}
+
+	@Override
+	public boolean isPropertyRedefinition(EObject sourceProperty) {
+		return iterate(sourceProperty, false, SourceTraceHelper::isPropertyRedefinition);
+	}
+
+	@Override
+	public List<? extends EObject> getSuperclasses(EObject sourceClass) {
+		return iterate(sourceClass, List.of(), SourceTraceHelper::getSuperclasses);
+	}
+
+	@Override
+	public ConstraintDescriptor createInstanceOfConstraint(EObject sourceClass) {
+		return iterate(sourceClass, null, SourceTraceHelper::createInstanceOfConstraint);
+	}
+
+	@Override
+	public boolean isInstanceOfConstraint(ConstraintDescriptor constraint) {
+		return iterate(constraint, false, SourceTraceHelper::isInstanceOfConstraint);
+	}
+
+	@Override
+	public EObject resolveInstanceOfConstraintClass(ConstraintDescriptor constraint) {
+		return iterate(constraint, null, SourceTraceHelper::resolveInstanceOfConstraintClass);
+	}
+
+	@Override
+	public String getClassName(ConstraintDescriptor instanceOfConstraint) {
+		return iterate(instanceOfConstraint, null, SourceTraceHelper::getClassName);
+	}
+
+	@Override
+	public ValueProperty getClassNameProperty(ConstraintDescriptor instanceOfConstraint) {
+		return iterate(instanceOfConstraint, null, SourceTraceHelper::getClassNameProperty);
+	}
+
+	@Override
+	public Collection<? extends EObject> getValidConstraintSourceClasses(ConstraintDescriptor instanceOfConstraint, EObject sourceClass) {
+		return iterate(instanceOfConstraint, List.of(sourceClass), (h, c) -> h.getValidConstraintSourceClasses(c, sourceClass));
+	}
+
+	@Override
+	public IGenerator createGenerator(EObject sourceClass) {
+		return iterate(sourceClass, null, SourceTraceHelper::createGenerator);
+	}
+
+	@Override
+	public String getName(EObject sourceElement, NameKind kind) {
+		return iterate(sourceElement, null, (h, e) -> h.getName(e, kind));
+	}
+
+	@Override
+	public int getMultiplicity(EObject sourceProperty) {
+		return iterate(sourceProperty, DEFAULT_MULTIPLICITY, SourceTraceHelper::getMultiplicity);
+	}
+
+	@Override
+	public boolean isViewOf(View view, DataContextElement element) {
+		return iterate(view, false, (helper, v) -> helper.isViewOf(v, element));
+	}
+
+	@Override
+	public boolean isSectionFor(Section section, DataContextElement element) {
+		return iterate(section, false, (helper, s) -> helper.isSectionFor(s, element));
+	}
+
+	private <T, R> R iterate(T input, R defaultResult, BiFunction<SourceTraceHelper, ? super T, ? extends R> function) {
+		R result = null;
+
+		for (Iterator<SourceTraceHelper> iter = delegates.iterator(); (result == null || Objects.equals(result, defaultResult)) && iter.hasNext();) {
+			result = function.apply(iter.next(), input);
+		}
+
+		return result != null ? result : defaultResult;
+	}
+
+}